Study Book


For the Training Course
PESTICIDES and Public Health
             ntroductory
1972
Environmental Protection Agency

OFFICE OF CATEGORICAL PROGRAMS

Office of Pesticides Programs
Division of Pesticide Community Studies
4770 Buford Highway
Chamblee, Georgia 30341

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Environmental  Protection  Agency
       William D.  Ruckelshaus, Administrator

OFFICE OF CATEGORICAL PROGRAMS
       David D.  Dominick, Assistant Administrator
OFFICE OF PESTICIDES PROGRAMS
       William M.  Upholt, Ph.D.,  Deputy Assistant Administrator

Division of Pesticide Community  Studies
       Samuel W. Simmons,  Ph.D.,  Director

State Services Branch
       Anne R. Yobs, M.D.,  Chief

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FOREWORD
This studybook is made available to students enrolled in the
“Pesticides and Public Health: Introductory” course to serve as an
aid in seeking an understanding of the conceptual and technological
considerations pertaining to pesticides. Such are important in
developing and maintaining effective programs in the fields of en-
vironmental health and environmental protection. The reader should
not be surprised to find the fundamental elements explained in detail
for each topic for we haveassumed that those attending the intro-
ductory course do not have a strong background in the subject based
on either study or experience.
For the most part these papers were prepared especially for
inclusion in this studybook. However, it should not be considered
a citable source. Original research data presented in these papers
will be published by the authors in another form in referenced
scientific journals. Should you be unable to locate the appropriate
reference for these data, we ask that you contact the author directly.
We take this opportunity to express our sincere appreciation to
the authors for their participation in this training course and to
wish you, the student, rapid progress toward our goal of adequate
protection of human health and of the environment.
Anne R. Yobs, M.D.fl
Chief, State Serv es Branch
Division of Pesticide
Community Studies
Environmental Protection Agency
iii

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TABLE OF CONTENTS
Foreword iii
Table of Contents iv
Faculty
Pesticides and Other Chemicals in the Environment 1
F. S. Lisella
Structure-Related Chemical Characteristics of Pesticides 11
L. A. Richardson
Introduction to Principles of Toxicology 21
1. B. Gaines
Metabolism, Storage and Excretion of Toxicants 25
M. F. Cranmer
Pesticides of Public Health Significance 29
H. G. Scott
Selection of the Proper Pesticide for the Job 35
H. G. Scott
Nonchemical Methods of Insect Control 37
1. J. Henneberry
The Diagnosis and Treatment of Acute Pesticide Poisoning Cases 51
G. A. Reich
Chronic Biologic Hazards of Pesticides:
Mutagenesis 53
S. Glenn
Teratology 57
B. R. Evans
Carcinogenesis 61
B. R. Evans
Man’s Exposure to Pesticides 65
A. R. Yobs
Pesticide Poisoning—-A Medical Examiner’s View 71
B. D. Blackbourne
Poison Control Centers and Their Functions 77
H. L. Verhulst
iv

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Pesticides in an Occupational Setting 81
L. Kaplan
The Investigation of a Field Problem of an Unknown Etiology 91
E. E. Moore
Sampling Procedures 101
B. L. Stevenson
Pesticides in Food and Feed 113
L. L. Ramsey
Selected Studies on Pesticides in Fish and Wildlife 117
1. W. Duke
Occurrence and Significance of Pesticide Residues in Water 125
H. P. Nicholson
Pesticide Problems in Water Hygiene and Their Correction 135
F. C. Kopfler
Fate of Pesticides in Soils and Crops 141
B. J. Stojanovic
The National Pesticide Monitoring Program 151
H. R. Feltz
Disposal of Waste Pesticides: Problems and Suggested Solutions 157
H. C. Johnson
Safety in Handling and Storing Pesticides 163
J. J. Boland
Proposed Federal Pesticide Legislation 167
E. R. Baker
Pesticide Use Patterns and Safety Aspects 173
L. C. Gibbs
Introduction to Chemical Analysis for Pesticides 179
A. Curley
V

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Emerson R. Baker, J.D.
Consultant
Division of Pesticide Conmiunity Studies
EPA
4770 Buford Highway
Chamblee, Ga. 30341
Brian 0. Blackbourne, M.D.
Medical Examiner’s Office
Jackson Memorial Hospital
1700 N.W. 10th Ave.
Miami, Fla. 33125
James J. Boland
Public Health Advisor
State Services Branch
Division of Pesticide Community Studies
EPA
4770 Buford Highway
Chantlee, Ga. 30341
I’brris F. Cranmer, Ph.D.
Perrine Primate Research Laboratory
EPA
P.O. Box 490
Perrine, fla. 33157
August Curley, M.S.
Acting Chief
Chamblee Toxicology Laboratory
EPA
4770 Buford Highway
ChairUlee , Ga. 30341
Thomas W. Duke, Ph.D.
Center for Estuarine & Menhaden
Research
Pesticide Field Station
EPA
Gulf Breeze, Fla. 32561
Burton R. Evans, Ph.D.
Project Officer
Community Studies Branch
Division of Pesticide Community Studies
EPA
4770 Buford Highway
Chamblee, Ga. 30341
Herman Feltz
Geological Survey
U.S. Department of Interior
Washington Bldg., Room 317
Arlington Towers
Arlington, Va. 22209
Thomas B. Gaines
Supervisory Research Pharmacologist
Chantlee Toxicology Laboratory
EPA
4770 Buford Highway
Chantlee, Ga. 30341
L. C. Gibbs, Ph.D.
Coordinator
Agricultural Chemicals Program
Federal Extension Service, USDA
Room 6427, South Bldg.
Washington, 0. C. 20250
Stanley Glenn, Ph.D.
Project Officer
Community Studies Branch
Division of Pesticide Community Studies
EPA
4770 Buford Highway
Chantlee, Ga. 30341
Thomas 3. Henneberry, Ph.D.
Chief — Vegetable, Ornamental and
Specialty Crops
Insects Research Branch
Entomology Research Division, ARS, USDA
Plant Industry Station
Beltsville, Me. 20705
Henry Johnson, Research Chemist
Ultimate Disposal Branch
Toxic Materials, Waste Management Office
EPA
5555 Ridge Ave.
Cincinnati, Ohio 45213
Louis Kaplan
New Jersey Community Study on Pesticides
State Department of Health
P.O. Box 1540
Trenton, N. J. 08625
Frederick C. Kopfler, Ph.D.
Chief, Chemistry Section
Gulf Coast Water Hygiene Laboratory
EPA
P.O. Box 158
Dauphin Island, Ala. 36528
Frank S. Lisella, Ph.D.
Assistant Director
Division of Pesticide Community Studies
EPA
4770 Buford Highway
Chantlee, Ga. 30341
E. Edsel I’bore
Acting Director, Pesticide Program
Division of Environmental Services
Kentucky State Department of Health
275 E. Main Street
Frankfort, Ky. 40601
1. L. Ranmey
Office of Compliance
Bureau of Foods, FDA
200 “Ca Street, S.W.
Washington, D. C. 20204
George A. Reich, M.D., M.P.H.
Director, Health Maintenance Organization
OHEW, Region IV
50 7th St., N.E., Room 557
Atlanta, Ga. 30323
1. A. Richardson, Ph.D.
leader, Traininq Unit
Perrine Primate Research Laboratory
EPA
P.O. Box 490
Perrine, Fla. 33157
Thomas N. Sargent, M.S.
Sanitary Engineer
Agricultural and Industrial Water
Pollution Control
Southeast Water Laboratory, EPA
Athens, Ga. 30601
Harold G. Scott, Ph.D.
Department of Tropical Medicine
and Parasitology
Tu•lane University School of
Public Health and Tropical Medicine
New Orleans, La. 70112
Samuel W. Simmons, Ph.D.
Director
Division of Pesticide Community Studiec
EPA
4770 Buford Highway
Chantlee, Ga. 30341
Bill L. Stevenson, Ph.D.
Assistant Chief, State Services Branch
Division of Pesticide Community Studie:
EPA
4770 Buford Highway
Chantlee, Ga. 30341
Boris 3. Stojanovic, Ph.D.
Professor of Agronomy
Mississippi State University
Box NY
State College, Miss. 39762
Henry 1. Verhulst, Director
Division of Hazardous Substances
and Poison Control
Bureau of Product Safety, FDA
200 NC 11 St., S.W.
Washington, D. C. 20204
Anne R. Yobs, M.D.
Chief, State Services Branch
Division of Pesticide Comunity Studie
EPA
4770 Buford Highway
Chantlee, Ga. 30341
vi

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1
PESTICIDES & OTHER CHEMICALS IN THE ENVIRONMENT
Frank S. Lisella
Until a few years ago, the words “environment” and “ecology” were almost exclusively
reserved for the scientist’s vocabulary. Today they are part of the layman’s vocabu-
lary as well. Much of the interest in the environment is due to significant strides
in technology which have greatly altered the spectrum of conditions affecting the life
and well-being of man. The correlation between technological progress and increased
concern for the quality of our environment has two sides. On one hand, advancements
in the control of disease and innovations resulting in increased agricultural produc-
tion have called for the widespread use of numerous chemical agents, causing, on the
other hand, concern about the proliferation of the environment with these chemicals
and their ultimate impact on the health of man. For example, the past 25 years have
been characterized by marked progress in the control of poliomyelitis, tuberculosis,
diphtheria, malaria, yellow fever, and numerous other diseases. As early as 1953, it
was estimated that at least 5 million lives had been saved and 100 million illnesses
prevented through the use of DDT for controlling malaria, typhus, dysentery, and other
arthropod diseases (1). The impact upon society of advances such as these has come
with mixed blessings, and there has been a definite shift in environmental hazards
from those with a microbial etiology to those of a chemical nature. The increased
productivity of farmland through the systematic application of pesticides may in turn
create problems of a public health nature. Among these problems are the potential
threats to the ecosystem, the hazards created by virtue of occupational exposure
through the formulation and application of pesticides, and the possible health effects
precipitated by chronic exposure to these chemicals.
Thousands of different kinds and combinations of gases, solids, and liquids can, and
do, pose potential health hazards to any, or all, segments of the public. It should
be pointed out that the home and occupational environments abound with chemicals
which are capable of inflicting immediate injury or death. Among these agents are a
wide variety of drugs, cleaning, polishing and disinfecting compounds plus an array of
substances such aslead—based paints, perfumes, lighter fluid, alcohol, turpentine,
gasoline, solvents and thinners, pesticides, and other materials. In fact at any one
point in time, there are approximately 250,000 chemical products which are capable of
causing human illness, death, or contamination to wildlife and the environment. It
has been estimated that approximately 40,000 new potentially poisonous products enter
the market each year. In less than 20 years, the use of synthetic chemical pesticides
has increased from a level of a few million pounds a year to nearly one billion pounds
annually. Today, almost 60,000 different pesticide formulations are now registered
in the United States and each of these contains one or more of the approximately 600
different pesticide compounds.
Pesticides have had a tremendous impact on the benefits we have been able to derive
from our society. If, for example, we are to look at some of our recorded history,
we would find that the literature is replete with writings pertaining to man’s
continual battle to eliminate or reduce populations of pests.

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In the early history of the colony of Virginia, Captain John Smith recorded that in
1609:
In searching our cashed corn, wee found it halfe rotten and the rest so
consumed with the many thousand rats increased from the ships, that we
knewe not how to keepe that little we had. This did drive us all to our
wits ende; for there was nothing in the country but what nature afforded (2).
Later in 1617, he wrote of rats again;
they spared not the fruits of the plants, or trees, nor the very plants
themselves, but ate them up . . . at last it pleased God, but by what means
it is not knowne, to take them away (2).
An arsenical compound, copper acetoarsenite (Paris green) was used as one of man’s
first pesticides; discovered in 1867, this chemical was first used to control the
Colorado potato beetle. Later pesticides played important roles in stemming outbreaks
of yellow fever, malaria, typhus, and other vector-borne diseases. While these dis-
eases have been virtually eliminated from the United States, they still remain as
threats to the health of people in other areas of the world, and pesticides play a
vital role in their control.
In addition to the prevention or elimination of disease, pest control measures are
necessary to provide the foodstuffs, fiber and other agricultural items necessitated
by our expanding population. The total quantity of food eaten each year by the popu-
lation in the United States is sufficient to stagger the imagination. The average
sized family of 4 people consumes over 2 1/2 tons per year. Meat, poultry, and fish
account for nearly one-half a ton, and dairy products close to three-quarters of a
ton; fruits and vegetables for well over a half a ton; flour and cereal products,
sugar, potatoes, fats and oils, and eggs add up to over four-fifths of a ton. Based
on these figures, the U. S. consumer averages more than a ton of food per person. per
year (3).
The food supply of the country must increase in relation to our expanding population.
During 1969, the number of farms in the United States dropped to a new low of
2,971,000. This represented a 54.1% decrease from the 6,500,000 farms 50 years ago
(4). Associated with the decline in farms is an obvious shrinking of the total number
of acres available for agricultural purposes. Obviously, if the nation’s food needs
are to be met, the productivity per acre must be increased. Pesticides and other
agricultural chemicals play a vital role in this connection. In fact it has been
estimated that approximately 70% of the most important agricultural crops produced
in the United States cannot be grown successfully without the use of insecticides.
Damage by insects lowers the general quality of fruits, grains, and vegetables.
Almost all corn and sorghum are planted with organic fungicides for the control of
decay. Weed control is necessary and carried out by the systematic application of
herbicides. More than 50 different species of insects prey upon stored food and
grain products. Insecticides play an important role in keeping damage of these com-
modities to a minimum. Even with the use of pesticides, the loss of agricultural
commodities may exceed $11 billion a year (3).
Thus, we are concerned with the widespread dispersal of pesticides and other chemicals
and consequently are placed in a “benefit vs. risk” situation. That is, the advan-
tages to our society must outweigh the detrimental impact the chemicals may have on
our environment. In order to ascertain this point, many investigations have been
conducted on their presence in the physical environment (air, soil, water) and on
their potential harm to humans and wildlife. Each of these points will be considered
briefly.

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3
Al r
The presence of pesticides in the atmosphere is an important health consideration.
Earlier investigations on pesticides in the atmosphere were devoted primarily to drift,
and only recently have a sampling device and appropriate analytical techniques been
developed. At the present time, ambient air samples are being collected from numerous
locations throughout the United States. Levels s high as 486.5 ng/m 3 of ethyl para-
thion; 162.5 ng/m 3 of methyl parathion; 117 ng/m 3 of p,p’DDT; to as low as 7.6 ng/m 3
of lindane have been detected at certain of the sample sites.
Atmospheric evaluations are also important in maintaining safe working conditions in
formulation, manufacturing, and packaging plants. These are important for two basic
reasons: first, to determine the actual magnitude of inhalation exposure of workers
(both fluctuations in exposure and also integrated exposure throughout the workday);
and secondly, to locate contamination sources for purposes of environmental control
(6).
The contamination of air by pesticides must be continually investigated in order that
we can obtain a clearer understanding between the relationship of these chemicals in
the air and human health.
Water
Pesticides may enter water supplies by direct and intentional application; by inad-
vertent drift into water from adjacent spraying operations; or perhaps, more commonly,
by runoff from pesticide treated areas within a watershed (7). During recent years
there has been a considerable amount of interest focused on the prevalence of pesti-
cides in surface waters. Our rivers and streams provide water for a large number of
quality-dependent users--including those served by municipal water supplies; agricul-
tural and industrial consumers; those desiring propagation of fish and wildlife for
aesthetic, commercial, and sport purposes; as well as those used for a variety of
recreational activities.
Runoff from agricultural areas is probably the single most widespread and significant
source of low level surface water contamination by pesticides (8). The transport of
these chemicals from the soil to water may occur while the pesticide is adsorbed on
eroded particulate matter, while in solution in runoff water, or by both means.
Pesticide formulation plants, production plants, firms that reclaim used pesticide
containers, operations that apply wool preservatives, textile plants that use pesti-
cides for moth proofing and similar industrial concerns are often responsible for
the discharge of large amounts of pesticides to a water course. Discharges of this
type may frequently be responsible for the mortality of various types of aquatic life
within the ecosystem.
The literature contains numerous references to situations where streams have been
grossly contaminated by pesticides either as the result of an accident or by sheer
carelessness. For example, in Florida a few years ago, a rancher instructed his ranch
hand to dispose of 50 four-pound bags of parathion dust (8). The bags were subse-
quently thrown into a stream which was the water supply for a small municipality down-
stream. Fortunately, a major disaster was averted because some of the bags were lined
with a polyethylene material which prevented the parathion from entering the supply;
and the community involved switched to an alternative supply of water. Residues of
parathion in the water were still detectable about two weeks after the episode.
In the aquatic environment, we are also concerned with the buildup or biological
magnification of pesticides in the flora and fauna. The accumulation of pesticides
may occur following the application of the chlorinated hydrocarbons, mercury, and
arsenical compounds and other heavy metals. In order for a pesticide to be biomagni-

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fied, the compound must be persistent in the physical environment, available to the
organism, and persistent once it is assimilated into the biological system (9).
Studies indicate that DDT and its metabolites, dieldrin, chiordane, toxaphene, and
heptachior may go through biological magnification in the food chain. Our ultimate
concern is with man who may consume the fish, crustaceans, or other components of the
food chain and thus contribute toward increasing his body burden of pesticides.
Soil
Pesticides in soils may seriously affect the marketability of crops. Pesticides set-
tling on soil may remain on the surface and later be moved by wind or washed off by
rain--or they may penetrate to some depth. Penetration will depend on the character-
istics of the pesticides and soil as well as on rainfall and other conditions. A
portion of the pesticides in soil may be absorbed by plants or other organisms, and
some may be translocated (10).
The accumulation of persistent toxic substances in the ecological cycles of the earth
is a problem to which man has to pay increasing attention.
Important factors influencing the persistence of pesticides in soils are the following:
1. Soil type: Pesticides persist longer in soils of high organic content, such as
muck soil; however, pesticides are absorbed into crops most readily from sandy
soils.
2. Soil moisture: The persistence of some pesticides is affected by soil moisture.
Moisture enhances the release of volatile pesticides from soil particles and
also influences the breakdown of other pesticides by way of hydrolysis.
3. Soil temperature: The soil temperature has a remarkable effect on the rate of
loss of a pesticide. Temperature influences loss through volatilization, as
well as breakdown of the pesticide by biological and chemical factors.
4. Cover crops and soil cultivation are also of importance. Soil cultivation
increases the disappearance of pesticide residues from soils (11).
Humans
Since 1965, there have been a series of research projects in operation to study the
effects of pesticides on human health. These projects are located in 14 different
areas of the United States and function through contracts with State health depart-
ments or universities. Each of these Community Study projects has three distinct ob-
jectives. The first is to determine the types and quantities of pesticides used in
the area from season to season and year to year. The second is the determination of
the levels of certain organochlorine pesticides in human tissue, and the third is a
prospective study of workers occupationally exposed to pesticides. This latter seg-
ment of the program may require 10, 15, or 20 years of continued observation to ascer-
tain the possible adverse effects of exposure to pesticides. These studies have
yielded much data which serve to increase our understanding of the effects of pesti-
cides on human health. At the Colorado project for example, studies have shown that
there is a significant correlation between levels of pesticides in house dust and
levels of pesticides in the blood of the members of the family. This suggests that a
person’s immediate environment may be an important source of pesticides exposure. The
Michigan Community Study has been investigating chromosomal aberrations by using cell
cultures from peripheral blood. The purpose of these investigations is to compare the
frequency of chromosomal aberrations among the exposed group to that of the control
group to determine if there are significant differences in the incidence of this con-
dition. Investigators at the Idaho project have noted that tissues collected from the
pheasant population in the State contained residues of mercury. This is of signifi-

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5
cance because the wildlife populations may in essence act as “sentinel animals” and may
signal human contamination as well. The Arizona Community Study has conducted experi-
ments to define the metabolic pathways of DDT. It is an accepted fact that DOT is
metabolized under anaerobic conditions to DOD and under aerobic conditions to DDE.
ODD is in turn metabolized to DDA, a water-soluble end product which is excreted in
urine. DDE is lipid soluble and is stored in adipose tissue. Recent data suggest
that levels of DOE in man may reflect exposure to DDE rather than DDT as is current1y
accepted. At the Florida Community Study, the interaction between the metabolism of
pesticides and drugs has been investigated. It has been shown that certain drugs in-
crease the metabolic breakdown of DOT in man (12).
In addition to the Community Study projects a human monitoring program is in progress,
the purpose of which is to determine on a national scale the levels and trends of the
more commonly used pesticide chemicals in the general population and in population
segments where intensive exposure to pesticides is known or suspected. Samples of
adipose tissue are being collected by 100 cooperating pathologists in 40 different
States. Primary emphasis is placed upon the detection of chlorinated hydrocarbons and
assessing the levels of these compounds, since these compounds are known to concentrate
and persist in human and animal fat. The data which have been analyzed to date indi-
cate that blacks have significantly higher concentrations than members of the white
population; also, persons living in the South have higher concentrations than those
in the North; and males tend to have higher concentrations than females, especially
among blacks. This data suggests that several factors influence an individual’s con-
centration of pesticides (12).
Wildlife
Pesticides play an important role in the management of fish and wildlife populations.
These chemicals are frequently used for the control of rodents and predatory animals
and for the removal of “rough” or “trash” fish from lakes and streams. Many of these
chemicals are highly toxic to animals and consequently there have been numerous in-
stances involving situations where animals other than the “target” organism have been
harmed. There is also concern over the buildup or biomagnificatlon of pesticides in
wildlife species that may be a source of food for man.
Other Chemicals
As with pesticides, we must be concerned with the health hazards associated with both
the acute and chronic exposure of persons to other chemical agents. A principal
source of concern pertains to the ingestion or the inhalation of chemicals at dosages
below the acute toxic levels. The long-term effects of exposure to low levels of
compounds that are 1 , 2, or 3 orders of magnitude over “background” levels are of par-
ticular concern. The problem is complicated by attempting to understand the effects
of low-level exposure to combinations of chemical agents.
During the past few years, there has been considerable publicity in both the lay and
scientific press with regard to three heavy metals—-mercury, lead, and arsenic. Each
of these agents creates special problems in our environment and will be discussed
separately.
Mercury
The hazards associated with mercurial compounds have been known since ancient times.
Inorganic mercurials were used as suicidal agents, abortants, and for therapeutic
purposes for many years. Mercurialism as a result of industrial exposure has been a
problem of concern for quite some time. The expression “mad as a hatter” exemplified
the presence of the illness in the felt hat industry. “Minamata disease” or methyl-
mercury poisoning due to the ingestion of contaminated fish occurred in a village
near the Minimata Bay, Japan, from 1953 through the 1960s. The condition affected at

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least 121 children and adults of whom 46 died. Attention was again focused on the
disease in 1964 and 1965 in Niigata, Japan, when 47 persons became ill, 6 of whom died
(13). These episodes, and an incident in Alamogordo, New Mexico, involving a family
of 7 in 1969 served to focus attention on the hazards associated with the presence of
this agent in the environment.
Mercurial compounds may enter the biosphere from any number of sources. Paper pulp
factories which use mercurials to prevent the growth of slime from fungi frequently
discharge PMA (phenylmercuric acetate) with their waste water. Paper products which
retain mercury and are subsequently combusted might contribute to atmospheric contami-
nation. Industrial concerns which use mercury electrodes in the production of chlorine
and caustic soda often release mercury into the air and water. Laboratories where
mercury is used in devices for analyzing blood specimens and central supply rooms in
hospitals where mercury is frequently used to clean scientific intruments can be a
source of concern. The runoff from agricultural areas which have been treated with
mercury-based pesticides are a frequent source of contamination to the aquatic environ-
ment. Fungi-resistant paints containing mercurial compounds may be a source of con-
tamination to the persons applying them and subsequently to others that may be exposed
to the painted surfaces. Mercurials are often used as mold suppressants by commercial
laundries, particularly those with diaper services.
The fact that all forms of mercury entering the aquatic environment may be converted
to methyl mercury, which is more toxic than other forms, and can be concentrated by
fish and other aquatic species is a problem of growing concern. Alkyl mercurials can
be introduced into the food chain by the consumption of mercury-treated seeds or meat
from animals which have been fed these compounds.
We must be continually aware of the health implications from mercurials and must con-
duct appropriate procedures to monitor their dissemination in the environment.
Lead
Despite modern scientific advances, lead poisoning or plumbism remains a unique public
health problem. The incidence of chronic lead poisoning in children is greater today
than in adults, and the fatality and disabling effects are much more marked in child-
ren. Occupational poisonings in adults as a result of inhalation of the dust and
fumes of inorganic lead are still of concern.
The environment is subjected to contamination by the leaching of lead from geologic
formations. It has been estimated that man’s activity in the United States alone in
1966 added approximately 700,000 tons of lead to the environment in that year. The
contribution of lead from tetraethyl lead in motor vehicle exhausts has been estimated
to be 185,250 tons (14). Contamination of. the soil and vegetation from air pollution
is related to traffic volume. Only a small part of the lead released from vehicle
emissions settles and accumulates in the vicinity of the roadways. The majority of
the material is transported by air currents and ultimately settles on the soil and
vegetation. Lead which has been recovered from surface waters has been attributed to
gasoline. This may result in the accumulation of lead in the tissues of fish.
Lead poisoning among children has been the subject of considerable investigation in
Philadelphia, Chicago, Baltimore, Cleveland and many other urban areas in the United
States. The study in Cleveland confirmed that the susceptible host for lead poisoning
is predominantly a pre-school child with a history of pica and that the agent is found
in an environment which is easily definable. Continuing investigations of children
residing in tenement dwellings, the development of improved analytical techniques and
environmental measures are necessary in order to keep lead poisoning cases among the
younger population to a minimum.

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Arsenic
Throughout history, arsenic has acquired unequalled notoriety as a poison. As early
as 2000 B.C., arsenic trioxide is reported to have been obtained from smelting copper
and subsequently was used as both a poison and for medicinal purposes (15). The word
“arsenic” appears to have been derived from the Greek word “arsenikon” meaning
“potent” (16). Copper acetoarsenite (Paris green) was used as one of man’s first
pesticides; discovered in 1867, this compound was first used to control the Colorado
potato beetle.
The use of arsenicals as insecticides is declining in the United States. On the other
hand, the use of the arsenical sodium arsenite as a herbicide has increased because of
the shortage of certain chemicals (2-4-D and 2-4-5-1 in particular) brought about by
the Vietnam war. In other parts of the world, the use of arsenicals (as herbicides
and insecticides) has apparently not declined or increased significantly in recent
years (17). The use of arsenic as a rodenticide has declined in the United States as
a result of the advent of the anticoagulant rodenticides.
One publication (18) lists 55 different situations and/or industrial processes within
which arsenicals are utilized in one form or another. For example, they are used as
decolorizers of glass, pelt preservatives, grasshopper bait, larvicides, amebicides,
additives to animal feeds, algicides, and a host of other applications. This same
publication points out more than 100 different population groups that may have occu-
pational and/or environmental exposure to arsenic. The list includes airplane pilots,
farmers, pest control operators, taxidermists, tannery workers, and many other
individuals.
Lead arsenate has been used extensively in the past for the control of insects asso-
ciated with apple orchards, vineyards, and tobacco crops. It is still used to a
limited extent for the control of the Japanese beetle and the boll weevil. Arsenic
trioxide is used mainly as a long—term soil sterilant. Sodium arsenite is fre uently
used as a nonselective spray to control all types of vegetation; however, since this
compound has a salty taste, its use in areas frequented by cattle is to be discouraged.
Sodium arsenite is also used for aquatic weed control and as a soil sterilant. Di-
sodium methyl sodium arsonate (DSMA) is less toxic to humans and pets and is used for
the control of Dallas grass in lawns and turf. Calcium arsenate is used as a pre-
emergence herbicide for the control of crabgrass and chickweed in lawns and turf (19).
In recent years the unique herbicidal properties of cacodylic acid and of methyl
arsenic acid were discovered. These simple acids, among the first organic compounds
known, are highly toxic to plants, but relatively nontoxic to man and animals. The
U. S. Forest Service has developed a hatchet that automatically injects cacodylic acid
when a blow is rendered to a tree——thus a new application for this material as a sil-
vicide has been created. Arsenic acid is used as a defoliant to facilitate mechanized
harvesting of cotton. As postemergence herbicides, the use of simple arsenicals is
unsurpassed. They leave token residues and permit germination of the new seed
promptly after the undesirable plants have been destroyed (15).
Thus, with this brief background, it can be readily seen that a significant proportion
of the population, if not all, is or has been exposed to an arsenical by one means or
another.
Man comes in contact with the arsenica1s in a variety of ways. The degree of exposure
may be related to a person’s occupation, the proximity to a copper smelter, the nature
of foods consumed, the type of soil in the area, the type of arsenical ingested or
applied for medicinal purposes, and a multitude of other factors. For example, shell-
fish have been shown to contain high amounts of arsenic when harvested from waters
containing 0.14 to 1.0 PPM of this chemical (20). Fish are known to concentrate
arsenic in their tissues. Residues as high as 40 PPM have been obtained from the
oils and tissues of black bass taken from waters in the southern United States. No

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arsenic was found in a specialized study of the public water supplies of the 100
largest cities of the United States. The maximum allowable concentration of arsenic
for potable waters in various countries ranges from 50 - 150 PPB. The usual daily
intake from water in the United States is estimated between 10 and 20 pg. (17). The
detection of arsenic in varying amounts in different foodstuffs has led to the estab-
lishment of tolerances for this chemical. At the present time, tolerances for arsenic
on foodstuffs range from zero in the Soviet Union to 4 PPM for arsenic acid in raw
cottonseed meal, 2.6 PPM on most foods, and 50 PPB in water in the United States.
Food products can become contaminated with arsenic in many ways. For example, apples
that have been sprayed with lead arsenate for codling moth control can contain as much
as 1 to 2 mg. of residue. Wine and cider can contain arsenic, but this is usually
removed during processing. Wine yeasts have been shown to contain arsenic in amounts
up to 150 - 180 PPM and baker’s yeast up to 17 PPM. Meat may contain traces of
arsanilic acid that has been used as a growth additive in cattle and poultry feeds.
Theoretically, these additives are discontinued several days prior to marketing and in
fact, the Food and Drug Administration allows a maximal animal tissue arsenic content
of 2.65 pg./g. The arsenicals must be removed from the feed 5 days before slaughter
so that the total level of arsenic in edible byproducts is below 1 PPM. At permissible
feeding levels of these drugs, the arsenic in muscle rarely exceeds 0.5 PPM even with-
out the 5-day withdrawal period.
Soil concentrations of arsenic can rise to several hundred parts per million after
years of spraying with lead arsenate and other pesticides. It has been postulated that
arsenic tends to remain in the top layers of the soil thus rendering it sterile to
the growth of some plants. Small amounts of arsenic may be translocated by plants
grown on heavily contaminated soils. The quantities of arsenic which have been obtain-
ed from plants grown under these conditions are not considered detrimental to human
health. Potatoes have been shown to contain 1 PPM of arsenic whether they were treated
with arsenical pesticides or not (21). While other organic pesticides are gradually
replacing arsenical sprays on food crops in the United States, the use of arsenic-
containing herbicides and defoliants has increased as indicated earlier.
The arsenic concentration of atmospheric dust has been determined by a number of workers
and is reported to be low or absent in most areas. Arsenic has been recovered from
the air of areas where coal is burned or smelting operations are in progress. The
recommended limit of arsenic in the air is 0.5 mg./m 3 . Only minute traces of arsenic
have been recovered from the air in the United States. In a survey of 8 English com-
munities in 1952, the arsenic content of air was found to be in the range of 0.037
pg./m 3 (As 2 0 3 ) to 0.075 pg. (18).
Recently, concern has been expressed over the arsenic content of phosphate ores. Phos-
phates are an essential constituent of many detergents. Thus, many individuals ex-
pressed the fact that these compounds may serve to further pollute our aquatic environ-
ment. As a result, the soap and detergent industry has directed their research efforts
toward finding suitable substitutes for the phosphates.
Conclusions
If we are going to evaluate the impact of these and other chemicals on human health,
there a number of avenues we must explore:
1. We must continue conducting long-term prospective epidemiologic studies to
determine the significance of low doses of chemical agents on human health.
These studies should include investigations of various combinations of chemical
agents; e.g., alcohol and carbon monoxide, pesticides and barbiturates.
2. Efforts must be directed toward the development of competency with regard to
pesticides and other chemicals by State and local health departments. These

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9
chemicals should receive the same emphasis that is currently being placed on
communicable diseases. Concurrent with program development there should be a
modification in philosophy, that is, that morbidity and mortality from chemical
agents like that from comunicable disease is preventable.
3. Morbidity and mortality regulations within individual States need to be
strengthened by adding the requirement that illnesses and deaths associated
with chemical agents be reported to the agency responsible for the collection
of vital statistics. This is imperative if we are to logically assess the
hazards associated with the use of chemicals.
4. Research must be continued into non-chemical methods of pest control. Concur-
rent with this, emphasis must be placed upon improved crop rotation practices,
the development of insect resistant crops and similar activities which will
eliminate or reduce the need for pesticidal chemicals.
5. We must continue to monitor the presence of chemicals in the diet, in the
atmosphere, and in our air, water and soil. Data collected from these monitor-
ing activities must be analyzed to determine their relationship to human health.
On December 2, 1970, President Nixon established the Environmental Protection Agency.
This Agency establishes at the Federal level a strong focal point for environmental
health activities. In a recent speech, William 0. Ruckeishaus, the Administrator of
EPA, said:
“Our goal must be to obtain the capacity to foresee and respond to emerging problems
so that the future will not overwhelm us. Environmental problems are hitting us
from every conceivable direction. Every time we look at a newspaper we are remind-
ed how ignorant we were yesterday or last year. Asbestos one week, phosphates the
next, mercury the week after--and we may be sure others will follow.
“We have been sitting on the sidelines expecting technology to bring us an unmixed
blessing of progress and prosperity. We set technology in motion, and expected
it to take care of us. In truth, technology was a substitute for thought.” (22).
Thus, as is pointed out, it becomes obvious our thinking must change if we are to keep
pace with our environmental problems.
Our goal for the future might well be found in the writings of Louis Pasteur who
indicated:
“Two opposing forces seem to be in mortal combat today. One, a force of blood and
death--ever devising new means 0 f destruction . .
“The other, a force of peace, work, and health, ever evolving new methods of
delivering man from the scourges that beset him.”
REFERENCES
1. Knipling, E.F.: The greater hazards—insects or insecticides. Journal of Economic
Entomology. 46:1, 1953.
2. Arber, E.: Travels and works of Captain John Smith, John Grant Publishing Company,
Edinburgh, Scotland, 1910 (Vol. I).
3. Walker, Kenneth: Benefits of pesticides in food production. The Biological Impact
of Pesticides in the Environment. Proceedings of the Symposium held August 18, 19
and 20, 1969, at Oregon State University, Corvallis, Oregon. pp. 149-153.
4. MacLeod, G.F.: Tomorrow’s agribusiness aid its educational needs. Agricultural
Age. September 1970, page 10.

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10
5. Unpublished Data. Air Monitoring Program, 1970. Division of Pesticide Community
Studies, Office of Pesticides Programs, Environmental Protection Agency, Chamblee,
Georgia.
6. Safe use of pesticides. American Public Health Association, New York, New York,
1967.
7. Nicholson, H.P.: Pesticide pollution control. Science, 158:3803, pp. 871-876,
1967.
8. Nicholson, H.P.: Pesticide contaminants in water and mud and their environmental
impact. Cornell University Agricultural Waste Management Conference, 1970, pp.
171-179.
9. The Biological Impact of Pesticides in the Environment. Proceedings of the
Symposium held August 18, 19 and 20, 1969, at Oregon State University, Corvallis,
Oregon, page 17.
10. Alexander, Martin: The breakdown of pesticides in soils. Agriculture and the
Quality of our Environment, AAAS Publication 85, Washington, D. C.
11. Lichtenstein, E.D.: Persistence and degradation of pesticides in the environment.
Scientific Aspects of Pest Control, National Academy of Sciences, Washington,
D. C., 1966.
12. Reich, G.A.: Pesticides and man. Proceedings of the Training Course - Pesticides
and Public Health-Advanced. Division of Pesticide Community Studies, Office of
Pesticides Programs, Environmental Protection Agency, Chamblee, Georgia. 1971,
pp. 85—91.
13. Hazards of mercury. Special Report to the Secretary’s Pesticide Advisory Committee,
Department of Health, Education and Welfare, 1970.
14. Shibko, Samuel T.: Heavy metals. Proceedings of the Training Course - Pesticides
and Public Health-Advanced. Division of Pesticide Community Studies, Office of
Pesticides Programs, Environmental Protection Agency, Chamblee, Georgia. 1971,
pp. 209-218.
15. Frost, Douglas V.: Arsenicals in biology: retrospect and prospect. Proceedings,
American Society for Experimental Biology. 26 (1) 194-208, 1967.
16. Buchanan, William 0.: Toxicity of ars enic compounds. Elsevier Publishing Company,
New York, New York, 1962.
17. Schroeder, Henry A., and Balassa, Joseph J.: Abnormal trace metals in man:
arsenic. Journal of Chronic Diseases 19:85—106, 1966.
18. Hueper, Wilhelm C.: Occupational and environmental cancers of the respiratory
system. Springer-Verlag Publishing Company, New York, New York, 1966.
19. Klingnian, Glenn C.: Weed control as a science. John Wiley and Sons, Inc.,
New York, New York, 1966.
20. Vallee, B.L., Ulmer, D.D. and Wacker, W.E.C.: Arsenic toxicology and biochemistry.
AMA Archives of Environmental Health. 21:132—151, 1960.
21. Wadsworth, G.R. and McKenzie, J.C.: The potato, with special reference to it use
- in the United Kingdom. Nutritional Abstracts. 33:327, 1963.
22. Ruckelshaus, William D.: The environmental crisis--our work has just begun.
Presentation at the National Press Club, Washington, D. C., January 12, 1971.

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11
STRUCTURE-RELATED CHEMICAL CHARACTERISTICS OF PESTICIDES
L. A. Richardson
In the area of chemical properties of pesticides, the only factor more
important than chemical structure, is the elemental makeup of the com-
pound. Chemical structure exerts a major influence on the toxicity,
reactivity, metabolism and degradation potentials, persistence, and the
analytical methodology useful in the elucidating and measuring of most
pesticide chemicals. Thus, a basic knowledge of the structural char-
acteristics of pesticides is absolutely essential to all personnel
responsible for any area of pesticide use, control, or analysis.
In the short period of time which we have to discuss pesticide chemistry,
one can only present an introduction to this fascinating and complex
subject. I will provide a brief picture of how these compounds exist in
space and how related chemical species differ among the “use groups”,
insecticides and herbicides. Secondly, I will discuss with you examples
of reaction, metabolism, and degradation of “type” compounds.
In order to impress upon you the complexities and importance of pesticide
chemistry, please note that there are at the present time some 600 chemi-
cal species, from which about 50,000 formulations are available for use.
While the problems in pesticide chemistry are not particularly peculiar,
the discussion of such a large segment of the chemical industry and the
understanding of such a discussion is indeed difficult. In actuality,
there are only about 100 chemical species ir primary use, about 20 of
which we will consider today. Chemical pesticides are produced at about
two billion pounds per year at the present time. This is about 10 pounds
per capita, or enough poison to kil1 every human being on the face of.
the earth. Fortunately, most of these materials are not persistent as
the parent compound; and although their decomposition, metabolism and
reaction may sometimes produce materials which are even more toxic than
the.parent, generally speaking, such products are not nearly as toxic
as the parent compound and in some cases are virtually innocuous. The
structural formulae we will inspect are only for the sake of explanation
and discussion; there is no attempt here to coerce you into memorizing
them since one of your references has each of them catalogued for you.
It would be well for you to note and recall important structural char-
acteristics and elemental differences among the chemical species. As a
first principle of segregation, we will consider these compounds, one
“use” group at a time, beginning with the insecticides.
Organochlorines are the most prominent of insecticides because they are
the oldest, the most used, and because their toxicity is a two—edged
sword. They are relatively non—toxic as far as acute symptoms are

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concerned, but they are of interest because they are cumulative and may
exhibit a more sinister or potential effect. We may also have either a
synergistic or an antagonistic activity within the organochlorinee them-
selves or between these materials and other chemical species. In the
organochiorins., we have a number of structurally related groups; first
of which is the chlorobenzilate or DDT group. The structural relation-
ship depends upon the matrix groups; in this case, we are considering
an aliphatic group surrounded by aromatic rings. While virtually each
pesticide has both a common and a chemical name, we will consider these
materials by their common name; and I will show you how one might arrive
at their chemical names. In the chlorobenzilates, we have an aliphatic
group as a matrix and the coapour.d . are chemically named on the basis of
this aliphatic group. In p,p’—DDT, the matrix is an ethane, thus the
final portion of the chemical name of this compound would be ethane.
On the number one carbon of the ethane group, one finds three chiorines.
Two phenyl groups are attached to the number 2 carbon and in the pare—
position of these phenyl groups we.find a chlorine. Consequently, the
chemical name for this compound would be l,l,l—trichloro—2, bis—para-
chlorophenyl ethane. The bis simply indicates that there are two phenyl
groups tied to the number two carbon.
If we look at o,p’-DDT, we find once again that the basic structure, the
matrix, is an ethane and again we have two phenyl groups tied to the
number two carbon. Once again, we also find that each of the phenyl
groups has a chlorine. In this case, however, the chlorine atom of the
first phenyl group is in the ortho position. In the second phenyl group,
or the prime phenyl group, the chlorine is in the pare position as we
found in p,p’—DDT. O,p’—DDT, then, is an isomer of p,p’—DDT, a posi-
tional isomer. Isomerism changes the characteristic of compounds. In
this case, p,p’—DDT is somewhat more toxic than is o,p’—DDT. We also
find that we can separate these materials on a gas chromatographic
column. Methoxychior has the same basic or matrix group, but the groups
associated with the aromatic rings are methoxy rather than chlorine.
We have, of course, changed the toxicity and the characteristics of the
compound. Methoxychior and p,p’—DDT are quite different from the stand-
point of toxicity and certain other characteristics. TDE or DDD is
another member of this group. In this case, we have only two chiorines
on the number one position of the ba ic matrix while the reactive groups
on the aromatic rings are exactly the same as in DDT. The relationship
between perthane and TDE is very similar to the relationship between
methoxychlor and DDT. The two chiorines on the aromatic ring of TDE
have been replaced by ethyl groups. Once again, the characteristics of
this compound has changed. Keithane is quite similar to p,p’—DDT except
that keithane has a hydroxyl group on the number two carbon whereas DDT
has a hydrigen. The characteristics of this compound are obviously
different from those of DDT and, as a matter of fact, the chemical nams
of the matrix group is different. This compound actually has ethanol
rather than ethane as its matrix. If we consider the matrix group to
be ethanol, we must change the order of numbering the carbons in the
molecule. Thus 1 Kelthane is chemically called 1,1—bis parachlorophenol
2,2,2, trichioroethanol.

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13
The second principal group of organochiorine insecticides is the cyclo—
diene, or as is sometimes referred to as the aldrin type. These com-
pounds are named on the basis of the cyclodiene group. The three
compounds shown in this first group have napthalene as the matrix.
Aidrin readily reacts to form the compound dieldrin. If you will
notice, there is a position on the aldrin molecule on which we can
institute a minor change and obtain the structure just below, dielirin.
The simple change between these two molecules is a result of oxidation,
or as it is usually referred to, epoxidation. The double bond between
the 6 and 7 position of aidrin, which is occupied by hydrogens, has
been broken with the addition of an oxygen bridge. Dieldrin is the
form in which you normally find the residue of aidrin applications. A
compound similar to aidrin which is referred to as isodrin, and to the
best of my knowledge is not used as a pesticide, also epoxidizes to the
third structure endrin. Aldrin and isodrin are isomers. Similarly,
dieldrin and endrin are isomers. These stereoisomers differ in their
structure only in that, if we would assume that the solid lines in the
chair configurations are In the plane of the screen, the epoxide group
in dieldrin would point back into the screen whereas the epoxide group
in endrin would point out toward the audience. Once again the proper-
ties of the two isomers are somewhat different. Endrin is considerably
more toxic than dieldrin. Dieldrin has a greater tendency to concen-
trate in human tissue, thus I suppose we could say it is more soluble
in fatty material. Finally, these two isomers are easily separated on
a chromatographic column.
The second subdivision of the cyclodiene, or aidrin group, consists of
the indene molecules of chlordane, heptachlor, and heptachior epoxide.
Since the matrix of these compounds Is the indene ring, they are named
chemically as substitutedly indenes. Chiordane Is the oldest of this
group and unfortunately Is still being used to a considerable extent
although its usage has decreased in favor of other insecticide agents;
one of them being heptachior. I say “unfortunately” for two reasons;
first, it is the most persistent chlorinated insecticide, and second,
It Is extremely difficult to analyze by gas chromatography because
chlordane consists of a number of isomers and these is.omers are sepa-
rated into a multitude of peaks on the gas chromatograph column.
Separate isomers show separate peaks on the chromatogram when using gas
chromatography and also give separate spots to some extent (usually a
streak) on thin—layer chromatograms. Consequently, they have a ten-
dency to mask other insecticides which might be present. Heptachior is
very similar to chlordane and is a popular insecticide although somewhat
less popular than it was a few years ago. Heptachlor Is never found in
human or animal tissues and is found in a rather reduced quantity in any
residue determination if one considers the amount applied. The reason
for this is that heptachior readily oxidizes to heptachlor epoxide.
This epoxidatlon Is identical to that of the epoxidation of aidrin to
dleldrin in that a double bond ie fractured and replaced by an oxygen
bridge. The resulting product is toxicologically opposed to that of
the DDT—DDE conversion. DDE is essentially non—toxic. Heptachior
epoxide, however, is just as toxic if not more so than the parent com-
pound, heptachlor.

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The third group of chlorinated insecticides consists essentially of a
single compound or, at any rate, a single compound represented by a
number of isomers; the hexachiorocyclohexane series commonly referred
to as benzene hexachloride or BHC. The compound pictured is lindane,
the gamma isomer, and the only isomer that is insecticidely active.
These are cis—trans isomers and one can readily picture the various
transpositions of chlorine and hydrogen in the structure which produce
the different isomers. As I indicated, gamma BHC (or HCH as it is some-
times correctly named), or lindane, is the only insecticidely active
isomer; however, the beta isomer is a good indicator of BHC contamina-
tion because It is the most persistent.
The fourth and final group of chlorinated insecticides consists of the
fumigate group. Fumigants are aliphatic compounds and, of course,
carry aliphatic names. Methyl bromide, ethylene dibromide, and
methylene dichioride are the most popular fumigants. Methyl bromide
is a potentially dangerous material whose formulations have been util-
ized as seed treatments and for the protection of residue problems in
that hydroxyl, sulfhydryl, and amino groups are metholated, and hydro—
bromic acid is released. Thus, we have an inorganic bromine residue in
the product. This pesticide also presents a hazard to the applicator.
The second principal group of insecticides consists of the organophos—
phates. We will talk about four groups of these compounds and point
out the differences in structure. From the chemical standpoint, organo—
phosphates are esters of phosphoric acid and are readily formed from,
and degraded to, substituted phosphoric acid and alcohols.
Two types of bonding are important from the standpoint of organophos—
phate characteristics and properties. The first, is involved with the
association between phosphorus and an isolated oxygen or sulfur. From
the standpoint of valence, this association is a double bond. With
respect to properties, it is a coordinate covalent bond; that is, the
phosphorus provides the electrons for the union rather than a sharing
of electrons as with the simple double bond or covalent bond. Such
relationship results in a more positive phosphorus. When this isolated
atom is oxygen, a more electronegative element, the phosphorus becomes
extremely positive and the compound becomes even more polar, more water
soluble, and more toxic.
The second bonding feature of interest deals with all the elements
directly attached to the phosphorus. For the most part phosphorus is
bonded to carbons only through oxygen or sulfur, however, a few com-
pounds have direct phosphorus carbon bonds. Since the carbon—phosphorus
bond is much more easily broken, such compounds are more readily de-
graded or converted.
I have previously stated that all organophosphate insecticides are
esters of phosphoric acid. Normally these compounds are named as esters
however, complexity often causes the naming system to break down and we
frequently find incorrect chemical names applied. Perhaps we should
consider some of the problems in naming and some of the hints, as to
structure, which we can gather from the chemical name. All phosphates

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15
contain various groups whose names are preceeded by a capital 5, 0, or
N. When such is observed in the name 1 it simply means that such groups
are tied to the phosphorus through a sulfur (S), or oxygen (0), or that
such group is attached to a nitrogen (N). The second major rule and
hint deals with sulfur, since sulfur is contained in almost all organo—
phosphate insecticides. Where a sulfur is in the coordinated, or iso—
lated, position with phosphorus, the compound resembles a ketone and
is referred to as a thiono phosphate or phosphorothionate. If the
sulfur is in the side chain linkage, the compound resembles a thio
alcohol and is referred to as thiolo phosphate or a phosphothiolate.
Finally, those compounds having a direct carbon—phosphorus bond are
called phosphonates and those having no direct carbon—phosphorus bonds
are referred to as true phosphates.
Organophosphate insecticides may be considered in each of four groups.
The first, alkene group is represented by bidrin, dichlorvos, and
trichlorofon. Sidrin and dichlorvos are phosphates. Trichlorofon is
an example of a phosphonate. Trichlorofon fits the category as a
“similar to” the vinyl group. The manufacturer removed the typical
vinyl grouping by saturating the carbons with a hydroxyl and a third
chlorine. None the less, trichlorofon is characteristically a vinyl
type structure. A second interesting characteristic of this compound
is that it is hydrolized to chloralhydrate, commonly referred to as
“knock—out” drops.
The second group of organophosphate insecticides is the aliphatic or
alkane type. The compound dimethoate is a good example of this group.
Pay particularly close attention to the side chain group attached
through the second sulfur atom. The particular group of interest here
is the CONH group, referred to as a carbamoyl, also referred to,at
times, as a peptide linkage which you probably recall from amino acid
groups as they combine to form proteins. This carbamoyl group is char-
acteristically similar to a carbonyl, except that it results from car—
bamic acid rather than carbonic acid. So, we have in this compound
a little of what we are discussing now and a bit of what we will be
discussing later, the carbamates. This is also an example of a phos—
phorodithioate, since we have two sulfurs in the molecule. Dimethoate,
often called cygon, is not terribly toxic and none of the parent com-
pound remains •as a residue. It is readily decomposed by hydrolysis.
The second compound, malathion, haà experienced a tremendous increase
in use in the last few years. We have been told that it is not partic-
ularly toxic but have had some difficulties with it. I suspect these
were concerned with large concentrations. Malathion does oxidize to
malaoxon; that is, the sulfur indicated by the arrow bond to phospho-
rus, is replaced by oxygen. Malaoxon is more toxic than malathion.
The fact that malathion is generally considered to be rather non—
toxic indicates that the positive phosphorus is in some way modulated.
The diester grouping of the side chain is interesting and may have
something to do with the reduced toxicity of this molecule. The third
compound in this series is phorate or thimet. This compound contains
two rather interesting points; one, the name. We might have a tendency
to look at it with three sulfurs and to name it as a phosphorotrithi—
oate. Actually, we consider the thioethyl group on the end of the side

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chain, and name the compound as a dithioate. The second interesting
point also deals with that third sulfur which can be oxidized to a
sulfoxide, that is one oxygen attached, or a sulfone, two oxygens. The
oxidation to a sulfoxide renders this compound considerably more toxic
than the parent. This is also true of any compound so constructed that
a sulfur can be oxidized to a sulfoxide or a sulfone. This oxidation
can take place on any sulfur which is not attached directly to the
phosphorus.
The third type of organophosphorus insecticide consists of the aryl,
or aromatic types. In essence, these compounds are acid anhydrides of
phosphoric acid and phenols. Some of the phenols perhaps may be a bit
difficult to recognize since they are also substituted. In the reac-
tion of phosphoric acid and phenol, water is split out, forming an acid
anhydride. Acid anhydrides are notoriously easily hydrolized; and as
they are hydrolized, they are once again returned to phosphoric acid,
howbeit substituted, and phenols, the alcoholic moiety. This phenol,
or alcohol, is generally also substituted.
Parathion is an extremely toxic compound and is readily converted to
paraoxon, which is, of course, more toxic than the parent. As the
oxygen analog, the phosphorus again becomes more positive, more soluble,
and more reactive. This is probably the reason for the increased tox-
icity. Parathion, as you know, is readily decomposed and metabolized.
The compound methyl parathion has a slight structural modification from
parathion, methyl groups on the ring Instead of ethyl. The reactions,
utilization, and toxicity of this compound are quite similar to para-
thion.
Ronnel Is a chlorinated phenolic phosphate, useful in qualitative anal-
ysis. Having chlorine, sulfur, and phosphorus moieties, we can use
diverse analytical methods and readily establish positive identifica-
tion. Guthion is a rather toxic compound which contains a diazo struc-
ture in the aromatic side chain. Actually, it is referred to as a
triazo structure and is named as a benzotriazine. The last compound
that we will look at in this group is EPN. The letters EPN stand for
O—ethyl—O—paranitrophenyl phenyl—phosphonothloate. Th.e name indicates,
and you will recognize from the structure, that this is again a phos—
phonate. That is, the phenyl group on the left Is tied directly to the
phosphorus, and the bond is between’ the phosphorus and the carbon. EPN,
as parathion, and methyl parathion, is hydrolized to paranitro phenol
The fourth and final group In the organophosphate insecticides consists
of TEPP. Tetraethyl pyrophosphate is a rather innocent looking com-
pound, but as I am sure you all know, is an extremely toxic one. I
doubt that tetraethyl pyrophosphate has any appreciable hazard except
to the applicator and to anyone accidentally exposed. TEPP unfortu-
nately is being used even today but in rather small quantities, fortu-
nately for the most part, by rather well oriented pest control operators.

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17
Carbamates are the third group of insecticides of particular importance
at the present time. Carbamates are named as esters of -carbamic acids
and their structures contain the carbamate stem OCONH. Carbamates are
reported to have low mammalian toxicity, but there are some instances
where they can be, and have been, made extremely toxic by reaction.
Carbamates are surface sensitizing; there have been cases of dermatitis
resulting from the use of carbamate insecticides. They produce some
questionably hazardous decomposition products and, certainly at this
point in time, need a considerable amount of investigation. Carbamates
are utilized as insecticides, herbicides, and fungicides. This doesn’t
mean to imply that the same compound can do all three jobs, but there
are members within this chemical species which can do one or the other,
and in some instances, more than one. I’ve classified the carbamates
as monomethyl, or n—methyl, and dimethyl, or n,n-ditnethyl. N—methyl
or n,n—dimethyl refers to the substitution of the nitrogen on the car—
bamate matrix. As we look at some of the structures, I can point out
much more easily just what I am referring to. The monontethyl compounds
are the most labile; they are usually solids, probably due to the
hydrogen bonding on the NH group. We will discuss the reactions more
completely later.
The first compound which we look at, sevin, one of the monomethyls, is
said to be a reasonably safe material. There is considerable investi-
gation currently in progress on the metabolism of this agent. As I
indicated, these are esters of carbamic acid; that is, carbamic acid
and an alcohol. The compound sevin contains a rather complex alcohol,
naphthol.
The second compound of interest is the one referred to as temik.
Teniik is basically an oxime. The carbamate moiety on the right is
mono-substituted by a methyl group, thus a monomethyl carbamate. On
the left of this structure you will notice that once again we have a
sulfur positioned between two carbon atoms. This sulfur oxidizes
rather readily to a sulfoxide, that is the addition of one oxygen, and
eventually to a sulfone, the addition of two oxygens. As the sulfoxide
the compound temik, which is referred to as temik sulfoxide, is ex-
tremely toxic. The sulfone, that is, temik sulfone, is not quite as
toxic but still more so than the parent compound. While the parent
compound may not be particularly toxic, it is readily and easily con-
verted to a toxic compound.
The second group of carbamates, the dimethyl, are much more stable to
heat and light and are usually liquid. Both their stability and the
fact that they are liquid appear to be associated with the lack of
hydrogen bonding. The lack of hydrogen bonding reduces the rigidity
of the compound with the resulting liquid state. In addition, methyl
saturation (not easily hydrolyzed) of the nitrogen enhances stability.
The compound dimetilan is an example of this group. The carbamate
matrix is on the right; however, it doesn’t look greatly different.
from the left side, which is referred to as a carbamoyl.

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The second use group of pesticides which we will consider is herbicides.
Herbicides, as I indicated to you in the beginning, are not well under-
stood, at the present time. Their potential, the toxicity of the par-
ent compound in many cases, and the decomposition products, and metab—
olites of many of the herbicides need to be studied extensively. We
have experienced a great deal of controversy and hopefully some Interest
over the use of herbicides in Southeast Asia. There are those who are
concerned about their long—term effect on the ecosystem.
There are certain chemical species of herbicides which may be poten-
tially dangerous, and in this discussion we will endeavor to indicate
those which could produce potentially hazardous decomposition products.
The first herbicide compound we will consider is CIPC, chioroisopropyl—
carbamate. Looking at the substituted groups on the amino of the
carbamate matrix, we notice a mono substitution; however, it is not a
mono methyl as we found in the insecticides. In this case it is a
mono substitution by an aromatic component; a chlorinated phenol. The
reactions on this compound are similar to those of insecticidal carba—
mates, with the exception that hydrolysis, in this case, has been shown
to yield analine, at least in soil.
The second compound, ordram, is a thiocarbamate which we can consider
to have a seven member ring. We can visualize this compound as disub—
stituted carbamate nitrogen. The carbamate matrix includes one oxygen
and one sulfur rather than the two oxygen atoms with which we are
familiar. Ordram to some extent is similar to temik in that the sulfur
can be oxidized to a sulfoxide or sulfone and as such will be consider-
ably more toxic.
A third species of herbicides is the substitutes ureas. Monuron is an
example of a urea herbicide and is a reasonably popular agent. I’d
like to call your attention to the urea stem in this case and to make
sure that you are able to differentiate between the urea and the car—
bamate matrices. You recall that the carbamate matrix results from
carbamic acid which Is NHCOOH. Consequently, the carbamate stem is a
substituted NH COO. Urea, on the other hand, is NH CONH , and here
it is substitu ed by a ring structure on the left whch ‘ooks very
similar to the compound CIPC. However, on the right side we have lost
the acid radical and returned to a substituted NH as we would find in
urea. These compounds are named as mono or dimet yl urea with the sub-
stituted products preceding that name. Thus, for monuron we have 3,4,
chlorophenyl—l,l dimethyl urea.
The fourth group of herbicides consist of the metallo—organics.
Methane arsonic acid is probably the best known, or was the best known
until recently, of the metallo—organics. It is usually applied as a
sodium salt and is a rather simple straight chain material. Cacodylic
acid, perhaps because of the furor over Viet Nam, is now the best known
of the metallo—organic herbicides. The chemical name of this material
is dimethyl arsenic acid. The toxicity of this material is in the area
of about a gram per kilogram.

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The fifth group of herbicides consists of the inorganics, such as
arsenic trioxide and arsenic pentoxide. Arsenic pentoxide in particu-
lar is very toxic and has a tendency to persist for a long period of
time in the soil. These compounds are comparatively simple straight
chain inorganics.
The sixth and seventh group of herbicides consists of the triazoles
and the triazines. Amino triazole, amitrole, is a very reactive
material and has been known to be goitrogenic in animals on continued
feeding of relatively high concentrations. This is the one that was
involved in the famous cranberry affair which some people have indi-
cated was only political. None the less, it is not particularly diffi-
cult to appreciate the concern, be it true or sham, because of the
triazo ring. Additional information that it is carcinogenic in large
concentration is perhaps some de.fense of the cranberry incident.
Simazine is an example of a symmetrical triazine. The azo ring struc-
ture does indicate some cause for concern with this particular material;
however, the compound, as appears to be true of all symmetrical tria—
zines, is very stable.
Dinitro—orthocresol (DNOC) is an example of phenolic herbicides, and
while it may be a bit extreme, I believe it presents a potential prob-
lem with phenolic compounds. DNOC is, of course, a very toxic material
and it is carcinogenic. It is an excellent weed control agent but is
being replaced by herbicides which are probably just as effective and
not quite as hazardous. An interesting point on DNOC is that a number
of years ago it was being prescribed as a weight control agent.
The ninth group of herbicides, the aniline compounds, can be repre-
sented by trifluralin. It is an interesting compound because it is one
of the few fluorine pesticides in use. While I have considerable con-
cern about analine compounds, this particular one seems to be of little
concern since it is relatively nontoxic and appears to be relatively
stable. Actually, only one propyl group from the nitrogen is lost and
the resulting product has a very low toxicity. The second compound in
this group is the one referred to s stain. Another name for it is pro—
panyl, or 3,4,dichloro propionanilide. This compound readily hydro-
lyzes to dichloro analin and is a compound worth worrying about. More
recently it has been shown that the analine compound in the presence of
certain toil micro—organisms is further degraded to a diazo compound,
also worth worrying about.
The tenth group, the amides, is represented here by diphenamid. It is
a dimethyl diphenyl acetamide. The compound is relatively nontoxic and
is apparently removed from the body as a conjugate found in urine.
Apparent ly, the conjugation takes place through the nitrogen with glu-
cose or possible other sugars. The amide group, of course, is the
CONH 2 ; the hydrogens on the nitrogen having been replaced by two methyl
groups. Differentiate this group from the urea compounds which are
NH ,CONH 2 with substitutions on the nitrogen; and from the carbamates
which are OOCNH 2 with substitutions on the nitrogen.

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The eleventh and final group of the herbicides which we will consider
is the organic acids. These are very persistent compounds howbeit they
are relatively nontoxic. Relative toxicity, of course, is sometimes a
bit difficult to visualize. Perhaps one of the best known of the or-
ganic acid herbicides is 2,4—D, and contrary to what we sometimes hear,
2,4—D is more toxic than DDT. Benzoic acid is not a particularly good
herbicide, but it is a good model since it is reacted with chlorine,
methyl groups, and amines, to produce effective herbicides. Benzoic
acid itself is relatively nontoxic; it is about as toxic as table salt.
Dacthal is a good example of the modification of benzoic acid to pro-
duce a useful and relatively safe herbicide. It is substituted with
both chlorine and methyl groups. The herbicide dalapon is an example
of a straight chain or aliphatic organic acid.
In this brief period of time we have emphasized the matrix and reactive
groups of type compounds of the most prominent pesticides. A limited
number of reactions have been discussed as well as some of the handles
available for analysis. It is my hope that you will appreciate the
diverse nature of pesticide chemistry, that you will be able to distin-
guish between the various chemical species involved and that we will
all continue to take steps to minimize the potential hazards of chemi-
cal pesticides.
REFERENCES
1. Guide to the Chemicals Used in Crop Protections , The Queens
Printers, Ottawa, Canada (1968).
2. Metcalf, R. L., Organic Insecticides , Interscience Publishers,
Inc., New York (1955).
3. Rosen, A. A. and Kraybill, H. F , Organic Pesticides in the
Environment , Advances in Chemistry Series 60, American
Chemical Society, Washington, D.C. (1966).
4. Chemistry and Mode of Action of Herbicides , Crafts, A. S.,
Academic Press, New York (1965).

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21
INTRODUCTION TO PRINCIPLES OF TOXICOLOGY
Thomas B. Gaines
1. Definition: Toxicology is a science that deals with the action of
poisonous materials on living cells and tissues, the response of
the living structures, and the detection and identification and
evaluation of safety of these poisonous materials.
2. Divisions of Toxicology, by Loomis:
Environmental Economic Forensic
Pollution Development of Diagnosis
Residues Drugs Therapy
Industrial Hygiene Food additives Medicolegal
Pesticides Aspects
3. Scientific Disciplines involved: Chemistry, biochemistry, pathology,
biology, pharmacology, physiology, biometrics.
4. Types of injury resulting from poisons:
A. Gross injury:
1) Death
2) Sublethal symptoms - dizziness, respiratory difficulty, vomiting,
tremor, convulsions, etc.
3) Retardation of development
4) Photo sensitization, skin irritation
B. Pathology:
1) Organ weight change
2) Microscopic changes in histology
a) Light microscopy
b) Electron microscopy
C. Hematological changes (WBC, hemoglobin, hematocrit, differential)
and changes in clinical chemistry.
D. Neurotoxicity - development of paralysis (triorthocresyl phosphate).
E. Teratogenesis - effect on fetal development:
1) Thalidomide incident
2) chlorinated dibenzo-p-dioxins, impurities in some compounds
F. Carcinogenesis - development of malignant tumors:
1) Very controversial with regard to pesticides
0

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22
C. Hypersensitivity
H. Induction or inhibition of enzyme activity such as microsomal
enzymes of liver.
I. Mutagenesis - genetic change
J. Changes in behavior
5. Factors influencing degree of toxicity:
Compound Sex
Dosage or exposure levels Age
Duration of exposure Interaction of compounds
Route of exposure Nutrition
Species and strain Disease
differences
Temperature and other .environmental factors
6. Toxicant must reach “site of action” to result in injury. This occurs
by way of the circulatory system after the chemical is absorbed into
the system from the gastrointestinal tract, lung, or percutaneous route.
En route to the “éite of action” the toxicant may be bound to proteins
and altered or removed, may be excreted by the kidneys or by the respira-
tory tract or sweat glands, or the molecule may be altered by certain
enzymatic systems in various organs, or may be deposited in storage tissues.
7. Factors affecting absorption:
1) Oral route
a) Compound
b) Type of solvent
c) Dilution of the dose
d) Fasting state of the animal
2) Dermal route
a) Compound
b) Solvent or physical state of material
c) Size of area of exposure
d) Condition of exposed skin
3) Respiratory route
a) Physical state of material
b) Efficiency of absorption in order of sprays, dusts, gases
c) Particle size - particles in excess of 2Op in diameter are
seldom inhaled. The upper respiratory tract tends to capture
particles between 5 and lOp size. The alveoli are most efficient
in capturing particles of 0.1 to 3.Op in size.
8. Selective toxicity - The injury of one kind of living matter without
harming some other kind with which the first is in intimate contact.
The living matter to be injured may be referred to as the uneconomic
species , and the matter which is to be unaltered as the economic
species .

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23
9. Measurement of toxicity:
A. 1-dose EDy or W 0 : calculated dose to produce some specific
effect or death o 507. of test animals.
B. 90-dose EDso or
C. Chronicity factor: I-dose LDyj (mg/kg)..fr-90-dose ID 50 (mg/kg/day)
D. Subacute index
S. ET 50 and LT 50 : time required to effect or kill 50% of test animals.
F. SC 50 and LC 50 : concentration required to effect or kill 50% of
test animals.
G. Response to graded dosage levels.
H. No significant effect level: dosage level at which no effect is
observed in experimental animals. In reality it may be an indi-
cation of our lack of ability to detect an effect. Any amount of
chemical that is taken into the body probably produces some effect.
10. Tests in Laboratory Animals:
A. Route of exposure:
1) Oral
2) Percutaneous
3) Inhalation
4) Parenteral by injection
B. Duration of exposure:
1) Acute toxicity - single dose, range of dosage levels given
to arrive at ID 50 value, lowest lethal dose, and lowest dose
producing signs of poisoning.
2) Subacute toxicity - generally considered 90-day test and if by
oral route chemical is usually given as a component of the diet.
3) Chronic toxicity - 2 years in rats and mice, possibly longer
exposure in dogs and primates.
C. Tests to detect teratogenesis and effect on reproduction:
1) Teratogenesis - pregnant female dosed during organogenesis
to determine effect on fetus.
2) Reproduction - animal usually fed chemical in diet at graded
levels and studied through 3 generations.
D. Potentiation - effect of combination of 2 chemicals in which the
effect is greater than additive, for example: 1/4 ID 50 of one
compound plus 1/4 ID 50 dose of other compound 1 LD 50 .
E. Sensitization: injection followed by delay. Then challenge
injection given resulting in substatnially greater reaction’
than after original injection.
F. Eye irritation: chemical instilled in eye and observations made
on effect on conjunctive (swelling), cornea (ulceration or opacity),
and iris (inflammation).

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24
References
I. Albert, A.: Selective Toxicity. John Wiley and Sons, Inc., New York, 1965.
2. Boyd, E.M. et al: The Chronic Oral Toxicity of Sodium at the Range of
the ID . Canad. J. Physiol. Pharmacol. 44:157-172, 1966.
3. Boyland, E. and Goulding, R.: Modern Trends in Toxicology 1. Appleton-
Century - Crofts, New York, 1968.
4. Frawley, J.P., Fuyat, H.N., Hagan, E.C., Blake, J.R., and Fitzhugh, 0.6.
Marked Potentiation in Mammalian Toxicity from Simultaneous Administration
of Two Anti-cholinesterade Compounds. 3. Pharmacol. Exper. Therap. 121(1):
96—106, 1957.
5. Ferguson, B.C.: Dilution of Dose and Acute Oral Toxicity. Toxicol. Appl.
Pharmacol. 4(6): 759-762, 1962.
6. Fredriksson, T.: Influence of Solvents and Surface Active Agents on the
Barrier Function of the Skin towards Sarin. Acta. Derm. 43(2):91-lOl, 1963.
7. Hayes, W.J., Jr.: The 90-dose LD 50 and a Chronicity Factor as Measures
of Toxicity. Toxicology and Applied Pharmacology, ll(2):327-335, 1967.
8. Lehman, A.J. et al: Appraisal of the Safety of Chemicals in Foods, Drugs,
and Cosmetics. Assoc. Food and Drug Officials of the U.S., Austin, Texas,
107 pp., 1959.
9. Litchfield, J.T., Jr.: A Method for Rapid Graphic Solution of Time-percent
Effect Curves. 3. Pharmacol. Exper. Therap. 97:399-406, 1949.
10. Litchfield, J.T., Jr. and Wilcoxon, l.A. Simplified Method of Evaluating
Dose-effect Experiments. 3. Pharmacol. Exptl. Therap. 96:99-113. 1949.
11. Loomis, T.A.: Essentials of Toxicology. Lea and Febiger, Philadelphia,
Pa. 1968.
12. Miller, L.C. and Tainter, M.L.: Estimation of ED 50 and its Error by Means
of Logarithmic-probit Graph Paper. Proc. Soc. Exper. Biol. 57:261-264, 1944.
13. O ’Brien, R.D. and Dannelley, C.F.: Penetration of Insecticides Through
Rat Skin. 3. Agr. Fd. Chem. 13(3):245-247, 1965.
14. Paget, G.E.: Methods in Toxicology. F.A. Davis Company, Philadelphia, Pa.
1970.
15. Snedecor, C.W.: Statistical Methods Applied to Experiments in Agriculture
and Biology. Fifth Edition, The Iowa State University Press, Ames, Iowa,
1956.
lb. Weil, C.S.: Tables for Convenient Calculation of Median-effective Doae
(LC 50 or ED Ø) and Instructions in their Use. Biometrics !:249-263, 1952.

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METABOLISM, STORAGE AND EXCRETION OF TOXICANTS 25
M. F. Cranmer
UPTAKE
1. Modes of Administration: Oral
Subcutaneous
Intramuscular
Intravenous
Inhalation
Percutaneous
2. Rationale for Different Modes of Administration
Ease
Speed of Action
Amount taken up by tissue where drug is active
3. Modes of Drug Preparation:
Encapsulated solids for oral administration
Solutions for parenteral administration
Extra ingredients added, e.g., thiopental plus bicarbonate to
increase solubility
Sustained release preparations
4. Gastric and Intestinal Uptake:
Factors determining uptake:
High for: low degree of ionization
high lipid/water partition coefficient
small molecular size, if molecule is water soluble
Some agents taken up by special membrane mechanisms, e.g., Na+,
sugars, amino acids, 5-fluorouracil
5. Degree of Ionization Determined by Henderson—Hasselbach equation:
pH = pK + log base form
acid form
Acid: - HA + A’ thus ionized form is base
acid form base form form A’
Base: HB + B ionized form is acid form FtB
base form
Examples: acids aspirin, barbiturates
bases caffeine, quinine, procaine
Most drugs are unable to cross mucosa when they are ionized; hence:
a) Rate of drug uptake determined by concentration of drug in
unionized form .
b) Equilibrium drug distribution between stomach and blood is such
that the concentrations of unionized drug are the same on
both sides of the membrane but ratio R of Drug between plasma
and stomach = acid forrnp + base formp
acid form 0 + base form 0
Where p is plasma and o is stomach or intestine

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26
Large difference between stomach pH and plasma pH assists uptake of
acids and hinders uptake of bases. Uptake of acids from stomach known
as ion trapping.
Rate of drug uptake and equilibrium drug distribution affected by
alkalinization of stomach with bicarbonate; this decreases acid up-
take and assists uptake of bases.
Drugs which are almost insoluble in water may be taken up sporadically
and haphazardly from the stomach since they do not dissolve in the lumen;
e.g., glutethiniide.
6. Inhalation
Gases inhaled and diffused across alveolar membranes; e.g., gaseous
general anesthetics.
High lipid solubility, small molecular size and high alveolar penTieability
result in almost instantaneous equilibrium of general anesthetics with
blood.
Aerosols are important route of entry of toxic substances; polluted air,
cigarette and marijuana smoke.
References: 1. D tll, C l i.. 3, pp. 21—33
2. Goldstein, pp. 106.129
DISTRIBUTION AND SPECIFICITY
1. Body Compartments Total Body Water 60%
Extracellular Water 17%
Circulatory Plasma Water’ 4%
Whole Blood Volume 8%
2. Apparent Volume of Distribution
The region of access of a drug may be determined from the drug con-
centration C in plasma water and the amount of drug administered X.
Apparent volume of distribution Vd = X/C
From ‘ 1 d it is possible to predict which water regions the drug has
access to.
Only valid for drugs which do not partition into lipid or plasma
protein and for drugs that are not rapidly metabolized or excreted.
Sucrose, mannitol, distribute in extracellular space.
Alcohol distributes in total body water.
3. Binding: Blood contains erythrocytes and plasma protein, both of which
may bind drugs.
Erythrocyte membrane may absorb gaseous and volatile anes-
thetics.

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27
Binding (Cant.)
Plasma protein binds a great variety of agents.
Proteins are: 1. y globulin
2. a and lipoproteins
3. albumin
a and lipoproteins bind cholesterol, steroid hormones.
Albumin by far the most important drug binding protein;
Constitutes 50% of plasma protein.
Albumin has specific sites for binding anionic, cationic and
neutral molecules. Sites are lipid soluble pockets in protein;
pockets also contain charges which attract opposite charges of
drug molecule.
Binding can be saturated, i.e., limited number of molecules may
bind albumin even at high drug concentration.
If drug binds with high affinity to albumin, this may affect
drug distribution, ra te of drug uptake into organs, metabolism
and elimination.
Drug interactions occur through competitive binding of two drugs
to albumin, e.g. ethylsulfadiazine + tolbutamide.
4. Distribution
Determined by:
1. Concentration of drug in blood.
2. Rate of transport across blood-tissue barrier
(through capillaries).
3. Rate of blood perfusion of organ.
Time for passage of blood volume through organs:
Brain 30”
Visceral organs 30”
Muscle 15’
Fat 3 hrs.
5. Transport
Determined by:
1. Lipid solubility.
2. Extent of ionization.
3. Molecular size, if drug is water soluble.
4. Polysaccharides and proteins also able to pass out
of capillaries by unknown transport mechanisms.
5. Blood brain barrier relatively impermeable to water
soluble and large molecular weight compounds.
6. Kinetics
A. Zero order absorption or elimination; when drug is absorbed or
eliminated at a constant rate regardless of concentration, e.g.
alcohol oxidation.

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28
B. First order absorption or elimination; when drug is absorbed or
eliminated at a rate which is proportional to concentration.
Most elimination is first order.
Half—life — time taken for drug concentration to drop to half its
original level.
ln . ..... = -kt where c = concentration
Co Co = original concentration
k = rate constant
t = time
Half-life t 112 related to k t 1 , 2 0.7
k
7. Dosage Regimens
If drug activity is exerted rapidly and ceases rapidly after cessation
of administration, constant infusion may be necessary, e.g. nitro-
prusside in hypertensive patients.
If drug activity is exerted slowly and drops slowly after cessation of
administration, then concentration of drug builds up slowly towards
plateau value. Drug may begiven at fixed intervals. However, if
drug action is required rapidly, then a high loading dose is given
initially to cause rapid buildup of drug, followed by smaller main-
tenance doses thereafter, e.g. chioraquine administration in treatment
of malaria.
8. Factors Affecting Drug Selectivity
1. Selective site of administration, e.g. local anesthetics;
drugs administered topically.
2. Selective distribution of drug.
3. Selective pH of drug activity.
4. Selectivity of receptor site or receptor enzyme of drug,
e.g., specific action of penicillin on bacterial all
wall synthesis accounts for efficacy and lack of toxicity
of antibiotic.
REFERENCES
1. Drill, pp. 25-30
2. Goldstein, pp. 130—194

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29
PESTFCFDES OF P1iBL C I1EALTIt SIGNIFICANCE
Harold George Scott
Tens of thousands of chemicals have CONTACT POISON - insecticide which kills
been evaluated for insect-, rodent-, upon contacting the outer body
weed-, and fungus-control. Hundreds of surface of an insect
these are in daily use in the pest
control field, and additional materials DEODORANT - material masking or de-
are being developed continually. As a stroying odor
result, even individuals engaged in
pesticide research find it difficult to E TIC - chemical causing vomitting;
stay abreast of this vast and rapidly added to rodenticides for safety
changing field.
Two aspects of pesticide hazard need EMULSIFIER - chemical which suspends
always be considered: (1) The toxic a pesticidal solution in water
hazard of the material to man and (2)
the total environmental effect of the FUMIGANT - pesticide which kills upon
pesticide. Decisions regarding use being inhaled
should always be based upon adequate
consideration of both of these hazard FUNGICIDE - chemical which kills fungi
aspects as well as upon effectiveness of
the substance. }ERBICIDE - chemical which kills weeds
Essential to comprehension of pesti— and other plants
cides is an organized knowledge so un-
familiar chemicals can be aBsociated DIPRECNA.NT - insecticide or repellent
with known materials and present back- infused into clothing or other
ground of knowledge can be used as a material
basis for understanding the new chemic-
als. As advances are made in pesticide INHIBITOR - chemical which prevents
knowledge, greater understanding of their insects from detoxifying an
toxicity to mammals is obtained. It insecticide
should be emphasized, that degree of
toxicity cannot be determined by the INORGANIC - chemical compound not con-
relative position of the pesticides in taming carbon
the charts. With any pesticide, all
necessary safety precautions should be INSECTICIDE - chemical which kills
taken, insects and related animals
The following four charts present
350 of the most commonly used pest MOLD INHIBITOR - dhemical which prevents
control materials in a practical system mold development in rodenticide
based upon a combination of chemical baits
structure and pest control effect.
NATURAL - found in nature, not
synthesized by man
GLOSSARY OF TERMS AS USED ON THE CHARTS
NON-SELECTIVE - kills all types of
ALGICIDE - chemical which kills algae plants
ANTICOAGULANT - rodenticide which kills NON-SUBSTITUTED - organic compound made
by interfering with blood clotting up of only carbon and hydrogen and
sometimes oxygen
AflRACTANT - chemical which draws an
animal to a place

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30
ORGANIC - chemical compound containing STERILANT - herbicide which kills all
carbon plant life in soil
REPELLENT - chemical which keeps an STOMACH POISON - insecticide which kills
animal away from an individual, upon being eaten
object or area
SYI RGIST - chemical without pest
RODENTICIDE - chemical which kills control effect enhances the
rodents and related animals effectiveness of a pest control
chemical
SELECTIVE - kills only certain types of
plants; does not harm other types SYNTHETIC - manufactured by man; not
found in nature
SOLVENT - liquid used for dissolving
chemicals WETTING AGENT - chemical which helps
suspend a pesticidal dust in water
SPREADER - substance which distributes
pest control chemical through a NOTE: Use of trade names does not
greater volume indicate endorsement.

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INSECTICIDES __________ THE CHEMICAL CONTROL OF INSECTS
Contact Poisons
INORGANIC ORGANIC
Synthetic Natural
REPELLENTS SUL FUR GROUP MERCURY GROUP ______________________________________
- ______________ ETROLEUM ALKALOID ESTER ROTEHOID RESIN
OI. ,h,I..I , ...id . GROUP GROUP GROUP GROUP GROUP
S ull g r CeIo .I ________________ _________________ _________________ _________________ _____________________
Ind.I o n. _______________ __________________________________ ________________ ___________________
Re ,g. ,. 612 LI..-. oIfu, F ..I 0.1 NI. .,In. Ppr.ihru R.i.n .ne
DI . ..iIiyIpI. h.I.i . K. ,e..n. A n.b..,n. P, ,. ,I.,, . . Cre on Oil
DIb..tyiphth.I.t. N.,n,.ei,n. C,n.nnn A... rphln
S.b.d ,II . (AII. ihnn) B.. 1I 0.1
H.lI.b.r. E.g. 0.1
ATTRACTANTS Stomach Poisons ____________ _____ By. ... T urp. n ... .
Quo..,.
ARSENIC FLUORINE OTHER
GROUP GROUP I GROUPS
Evg...l _________________ __________________ j
Tst r.pI nyl . .I .t. ___________________ ____________________
An.th.I A,..... ftIo.Ids 5.dI . II 0 .,Ide PI..sph u. p . . 1 .
U.,.Id.hyd.
A I L..d 1 e ,• 1080 B....
OSOO C r,.II.. Ten., .n lIc
S. O Oh.,In. C.pp. . SALP
Sed,o II....Ilo. .
Perle green Th.IIIua suit 0 ,•
I MPREGNANTS
- — ‘ •
B•fl•Il NON ORGANIC ORGANIC ORGANIC I ORGANIC ORGANIC
Be. .uyIb.n...t . SUBSTITUTED CHLORINE PHOSPHORUS NITROGEN I SULFUR THIOCYANATE
B.. e. s.I n . HYDROCARBONS GROUP GROUP GROUP GROUP GROUP
U. 1960
MI ,In F.n. eId.hpd. P.ntechleroph.nsI M.IeIh,en D,n.ir.ph.noI A,ea,i. L.rhen.
Eel.. M., eId.h,d . BHC D,e..no . ONOC _______________ TI..... ,.
b.N ephih oI P. reIh,.n SuIte...,. Lore
B.e..I..r Loden. ONOCHP
X.n II . sn. TEPP Ph.n.lh...,n.
M.iI , o.y hI.r ONOSOP
F.,be. . EPN G .n . ,.I
AUXILIARIES Fumigonts ________ DDVP Aceb. .... . ________
Spa..g..i. Hydrog...cyenId. O.bro.. Ke,.lhen. Dn e. l.I.n
Inhib. .... Methyl h...Id . “ G..th... , Pr.Ien Py,.I.n
Sol oanIs Carbon i. r.chl.r,ds H.ptechl.r DIP,.,..
Chord... D.n.rr.n .pb h.I
E e.uI..Iisro E ,h.d. Eni. .
W.Iting Ag.nl. Sulfur d....d. Ald,.n a.,,.. D.n, l,a.n. sole
O..Idnn
Spi ..d.,. N.ph,I,.l... Ronn el
End,,n flltreflesy ate
.-DI.I ,I. ..b.ns.no HAROLD 000500 eCOTT. Pu 0 Dicopihon
O.I..a ,s p-Dlchl ot.ben .en . D..,h..,.
out.. Pu.. coc
_______________________________ 0.I.,, ..,.d Hydso..rbenu
(A)
—

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THE CHEMICAL CONTROL OF RODENTS
AITRACTANTS
___________ Anise ____________
_________________ Fish _________________________
________________ Meat _________________
____________________ Grim ______________________
_________________________ Fruit ___________________________
____________________ Nuts
Molasses
Water
SYNTHETIC
POISONS I 1
INORGANIC ORGANIC
_______ NATURAL ______
POISONS
Red squill
Strychnine
RODENTICIDES
REPELLENTS
Cat
TNBA
DR.1669
TMTD
ZAC
PhenvI-nifro gxopene
DEODORANTS
n-Butpl-phthalimide
AUXILIARIES
Neuticleum .lpha
Pine alt
I WinL er . oil
Binders
Emetic,
Decoioriza rs
Mold Inhibitor,
Zinc
hcsol llds
Arsenic
trioside
Arsenic
pentoxide
Thallium
sulfate
Barium
carbonate
— FUMIGANTS
ANTICOAGULANTS
GROUP
Yellow
— — —I ’ —- . .-
0Th ER
GROUPS
ANTU
1080
1081
DOT
Endr ln
PREPARED BY
Harold George Scott
REVISED 1969
DHEW. PHS, CDC
INORGANIC ORGANIC
Sulfur Hydrogen
dioxide cyanide
Methyl
bromide
iNDANEDIONE ]
SERIES
HYOROXYCOUMARIN
SERIES
Weifarin
Warfucid,
Protin
Fumailii
Fumasol
Tamarin
Pinl
Pivalyn
Dtphac ln

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INHIBITORS
_________ -
ammonlum sulfate calcium chlarai. arsenic pentesld.
AMS calcium chloride sodium ara.nit.
cepp.r sulfa,, sodium chlorate
ferrous ammanlum podium chloride
sulfate
iron sulfote
sulfuric acid
.thpl.2 14 1
. sal.ic hydraald.
AUXILIARIES
Saul suflers
saiv.nts
sprewiera
Wetting ag•nis
CARBAMATES PHENOXYS
2.4-0
2. S.D
2.4. 5-T
3.4-0
4-C
MCP A
Satan.
silo..
TRIAZINES PHENOLS
a.sltrol DNOC
atrsaln. ONOSAP
propaz lne OHO SaP
silts sin
“is tin.
CHEMICAL CONTROL OF WEEDS
HERBICI DES
NON-SELECTIVE
( SOIL STERILANTS)
ORGANIC SULFATES CHLORATES MERCURIALS
ALGIC IDES
•.pp.r sulfa ,.
dl tll.n.
gletaitsay itla
H ADA
PHENOLS UREATES THIOCYANATES PETROLEUM Non-substituted
INORGANIC SULFATES
,
dIsulild.
I OMTT
I bl.(.thpl
I 1c)
I i x
CDAA
HCA
PBA

dalapon
TBA
TCA
TCB
I I

I I

-
I OCU i ammenlum i i
dlursn I patassism
I I I I
OMU I Ihl.cyanat.
I .
ODMU I thiacyanet. I I
.rbon I
f.su,on
masuron I
dl•SSI fuel I I
fuel all
I
gasoline I I

.d.l.etsu i I
kerosene
ateddard
I
acrolvin
I

I


mercury
acetate
I I
i I

pentachlero-
phenol
elIpI alc.h.l
MMAI_
MTAI_
I I
I I

n.dluos p.nt
chl.rapbonat.
NPA
PMA
BORATES
n.buron
P DC
CHLCRATES ARSENATES
borax
SELECTIVE
boron t ,loeid.
sodium borate
sodium m.tobo,ot.
sodIum pentabarat.
sodium t.traborat.
SOIL FUMIGANTS
ORGANIC
calcium cysnote
calcium cyanimid.
CDEC
CIPC
EPTC
IP C
SM DC
chlorpicrin
•thyl.n. dibrosi.d.
a..thyl bra.sid.
potassium cyanat.
INORGANIC
W A R N I N G
We.d cont,ol via chemicals Is a useful .sthod
for ot .manf of mosquIto., asd other onlmal
di seas. vsctors 1 h.w.ver, herbicides d ttage
us.ful pleats as well as w..ds. Sam. ars inflam-
mablo. Sam. r.qulr. special quplicatian tech-
mqu.s. All are toac to mon. Us. with cww
arid follow directions on the lth.i
U S DEPAIIThENTOF
HEALTH. EDUCATION. AltO WELFARE
PUDLIC HOALTH 5UV ICC
Cnaicsbl. DiseaSe C.al.r
Attests. Oea,als
hAROLD 05000 1 ecory. P 0. — lest
I carbon dl sulfide

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ECONOMIC FUNGICIDES
CTT(p) •
Di TP (p)
I ‘1 1 (p)
I TP (p)
NIl T(p)
> Bromine group
Sulfur group
Cool-tar group
Copper group
Cu A A
CuN (p)
Cu NP H
CuQ
H diphenyl J
glyodin (a)
aOgrOrn
cnlograen
care sos
canasan N
ch,pcota
L-224
m a,cu,an
mariolite (e)
inerthiolate
my con
N-5-E
panogen
PM A (p & a)
PMU
5mb seed
ueedox
somenon
sam a son
semesan bel
setreta
copper arsenate
Copper carbonate
Copper hydroxide
copper oxychierida
copper phosphate
c-OS
Cuprus oxide (p)
Cu-Zn chroinata ( )
V V
Mercury group Sulfur group
colomel -
mercuric chloride
mercuric oxide
V
Zinc group
I ( zinc oxida hydroxiaa [
W A R N I N 0
Some fungicides damage plants as well as fungi,
some ara inflammable, some require special
application tachriiquas, and all ara tonic Use
with care — and follow directions on the label
V
Borax group
U S I)IPARTMFNTOF tll”iL.Ttt.IDIICATION. ANt) gFLrAR )
PUBLiC HEALTH SERVICE
.5!. D I . . . .. C ...i.t
Tr.ini.i B,..i.ii
AII.si. G.a. O.
WAYNE 0 BROWN. 1961
—ORGANIC
HALOGEN COMPOUNDS
Chlorine group
B H C (p)
Iodine group
I thiram(p&e) I
AlT (p)
ciWtan (a)
dichione (a)
DDDM(p )
P C P (p)
P D B (a)
phygen
TCP(p)
> Non-substituted
Hydocarbon group
BDIT (p)
BrDl T (p )
CIB(p)
cabolineum (p)
Coal-tar
TCQ (p)
ZIP
Mercury group
Nitrogen group
LPB (a)
LOB (a)
lerbam (a)
maneb (e)
nabam (e)-
NaDNOC(e )
PC N C (p)
qua) ammonias
salicylanilide (a)
—INORGANIC
Copper group
zuneb (a)
basic copper sulfate
ziram (a)
bordeaus mu.ture (p)
SOIL
FUM I GANTS
CBP (a)
chiorani I
chiorepi cnn
dichleropropeusa
ethylene dubromide
formaldehyde
HO B (a) _______
sulfur
m.ihyI bromid.
sulfur-lime (p & a) I
t,ibasic copper sulfate
borax (e)
(p) — preventive
(a) — eradicative

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35
SE1 CTION OF THE PROPER PESTICIDE FOR THE JOB
Harold George Scott
Selection of the proper pesticide should begin with a thoughtful analysis
of the objectives of the control program and of the possible ways to achieve
that objective. Pesticides may not be a desirable technique. If it does
seem advisable to use a pesticide, the exact placement of the pesticide in
the control system should be plotted out and the following factors analyzed:
1. EFFECTIVENESS - which pesticides are best able to do the job?
2. AVAILABILITY - which pesticides are readily obtainable?
3. COST - What expenses does each entail in materials, applicator
equipment and labor?
4. INITIAL MAGNITUDE - how rapidly do the various pesticides
produce what result?
5. EVENTUAL MAGNITUDE - how long do the pesticides last?
6. REACTION - how much resistance can be expected from the pests?
7. SPACIATION - how far from place of application will each
pesticide spreadZ
8. SAFETY - What hazard does each pesticide represent to man?
to the environment? What general precautions are needed for each?
9. DISPOSAL - How will empty containers and unused pesticides be
disposed of or stored?
10. LEGALITY - what special precautions are needed for your uses?
What restrictions exist on the use of each pestic1 de?
11. C 1PETENCE - Do you have properly trained personnel available?

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37
NONCHEMICAL METHODS OF PEST CONTROL
Thomas J. Henneberry
The growing concern of the public and scientists concerning the demonstrated adverse
effects of insecticides has stimulated renewed entomological effort to develop effec-
tive, efficient insect controls which are compatible with and have minimum effect on
the complex components of the agro—ecosystem. The methods of insect control avail-
able to the entomologist today are the results of more than one—hundred years of
careful observation, experimentation, and creative thinking by scientists concerned
with insect control. The present era of pest control using synthetic chemicals
began during World War II. The benefits to mankind attributed to the use of these
chemicals for insect control is inestimable. However, problems have arisen. Adverse
effects on parasites and predators, chemical residues, arthropod resistance to chemi-
cals and high cost and temporary nature of the treatments have been of increasing
concern to everyone involved in pest control.
Other methods of insect control; varietal resistance, biological agents, sterility,
cultural techniques, repellents, attractants, and many other procedures have long
been recognized and reco=ended by scientists as having potential in Insect control
programs. The Entomology Research Division of the USDA began to reorient its research
program in 1955 from major emphasis on conventional insecticides to more selective
chemical and nonchemical methods to control major insect pests 1 . At the present
time approximately 16% of the resources of the Division are devoted to insect control
using conventional insecticides as compared to 84% in research to develop alternative
methods of control and fundamental entomology studies as shown in the tabulation.
Percent of Resources
MAJOR LINES OF WORK By Group Subtotals
CONVENTIONAL INSECTICIDES 16 16
OTHER CONTROL METHODS
Biological control 14
Insect sterility 12
Plant resistance 7 51
Cultural and mechanical methods 4
Attractants, hormones, etc. 14
FUNDAHENTAL ENTOMOLOGY
Basic insect biology 19
Metabolism 2
Taxonomy 6 33
Insect transmission of plant
and animal diseases 2
Apiculture 4 ______
100%

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Resistant Plants
One of the most satisfactory methods of preventing damage to plants is through the
development of varieties resistant to insect attack. Painter’ broadly characterized
the causes of plant resistance as follows:
1. Preference and Non—Preference
Plants may not be acceptable to insects for
oviposition, food, or shelter because of color, odor,
lack of chemical or physical stimuli and/or other
similar factors.
2. Antibiosis
Plants may have an adverse effect on the biology
of the insect and in some cases feeding on them may
result in death.
3. Tolerance
Plants may be tolerant to insect attack and sustain
numbers that would severely impair or kill more susceptible
types.
One of these mechanisms or a combination of all may make plants resistant to attack.
Outstanding achievements have been made in developing wheat varieties resistant to
Hessian fly ( Myetiola destructor (Say)) and wheat stem sawfly ( Cephus cinctus Norton)
alfalfa varieties to spotted alfalfa aphid ( Therioaphis maculata (Buckton)) and corn
varieties to European corn borer ( Ostrinia nubilalis ( Hubner)) 3 . At one time the
Hessian fly caused high economic losses in the United States. Today these losses are
minimal largely due to the development of resistant wheat varieties. At least 23 are
now available to the farmer. Similarly, the dramatic discovery of a solid stem wheat
variety which was resistant to wheat stem sawfly resulted in an estimated $4 million
annual saving to wheat farmers.
The spotted alfalfa aphid was first discovered in New Mexico in 1954. A crash program
was initiated in 1955 and in only 3 years Federal and State scientists working coopera-
tively developed and released the resistant variety Moapa. Subsequently, many other
resistant varieties have been developed. Estimates of savings to the farmer range
from $35—la million annually.
The most destructive pest of corn in the United States is the European corn borer
which caused an estimated $350 million damage in 1949 alone. A continuing program
of incorporating corn borer resistance in hybrid con has been a major factor in
reducing these losses more than 60% on an annual basis.
Continuing research in all of these programs is essential since experience has taught
us that insects can and do change biologically, adjusting and adapting to the types of
plants grown in their environment. The identification and incorporation of multiple
resistance to an insect pest is especially desirable. If the insect readily adapts
to one resistance mechanism, it will probably not adapt to the other, and thus the
variety will still be useful.
Often, the level of insect resistance found in commercially useful varieties is not
adequate to prevent economic damage by an insect pest. However, such resistance may
still be useful because it can reduce the frequency of application and the amount of
chemicals required to produce adequate control. This in turn reduces production
costs, pollution problems, and may have a sparing effect on parasites and predators.
Research in developing plants resistant to insect attack is a challenging and new
area of study. Resistance to pests exists throughout nature and needs only to be
discovered, identified, and applied to solve many of our serious pest problems.

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39
Sterility Methods
Methods of using induced sterility to control or eradicate insect populations are
among the most significant recent contributions to entomology. The best known, the
method of sterile insect release, involves the sustained overflooding of native popu-
lations with sterile insects of the same species at densities that are high enough
so little probability exists of fertile native matings. The method was hypothesized
about 1937 by Dr. Edward F. Knipling, Entomology Research Division, U.S. Department
of Agriculture. Then, after many years of research, it became scientific fact when
screw—worm flies, Cochliomyia hominivorax (Coquerel), sterilized by irradiation with
cobalt—60, were released at the rate of 800 per square mile on Curacao Island in the
Nether4nds Antilles in 1954. Eradication was complete about 3 months after the first
release 4 . Subsequent releases of sterile screw—worms in Florida (The Southeast Screw—
Worm Eradication Program) and in the Southwest were similarly successful 5 ’ 6 . Expendi-
tures in the Southeast screw—worm sterile release program were less than $10 million,
and the estimated savings to cattle growers in that area since its conclusion probably
exceed $100 million. In the Southwest program the investment is about $20 million,
but livestock men estimate savings of as much as $400 million.
A second method, chemical sterilization of insects, is now being investigated. Chemi-
cals that have sterilizing effects on insects have been known for many years. However,
interest in their potential In insect control programs was renewed when the screw—worm
eradication campaigns were successful and LaBrecque 7 found 3 alkylating agents that
induced sterility in both sexes of house flies, Musca domestica (L.). If effective
methods of using these sterilants can be developed, it is possible that they can be
used both to sterilize insects for mass releases and also to sterilize a native
population.
The Method of Sterile Insect Release
Suppression of insect populations by the method of sterile insect release requires
the mass rearing of the subject species, the inducing of sterility, and the sustained
release of the sterile insects into the wild population in such numbers that the pro-
bability of a fertile native mating becomes progressively more remote as the releases
continue. This constant pressure on reproductive potential results in a marked
decrease in and theoretical elimination of the insect population within a relatively
few generations.
For example, Knipling’s 8 calculations indicate that when 90% of the total insect
population in the first generation consists of released sterile insects and the same
number of sterile insects are released each subsequent generation, the native popula-
tion will be eliminated by the fourth generation. In contrast, a program of control
with insecticides which ki4.ls 90% of the insects in each generation would theoretically
require more than 10 generations to eliminate the population. The initial effect of
both systems is the same, but the sustained release of sterile insects each succeeding
generation has a progressively greater effect on the reproductive potential of the
native population; applications of insecticides produce a constant pressure each
generation and therefore require more than 2.5 times as long to produce the same total
effect.
The es entia1 prerequisites that must be satisfied for the elimination of a particular
insect include an efficient method of mass rearing, techniques of sterilization that
have no adverse effects on the mating capability, competitiveness, or vigor of the
species, a practical and efficient means of disseminating the sterile insects into
the native environment, and assurance that the released insects will not create undue
hazards or loss to crops, livestock, or man 8 ,
Another essential prerequisite is that the Initial releases of sterile insects must
produce high enough overflooding ratios of sterile to native insects to start a down-
ward trend in the population. Information about the distribution of the native

-------
40
population and quantitative and qualitative information about the population density,
particularly at the low cycle of the population, is therefore essential. Sterile
Insect releases are highly efficient when the population is small; conventional insec-
ticides are least efficient against small populations and highly efficient when
populations are large. Thus, the optimum time to begin a program of sterile insect
releases Is when the active native population is at its lowest level, and the proper
timing for all releases must be critically and exactly determined.
Also, a sterile insect release program will be effective only when the reproductive
potential of the total population, or of a large segment of it, Is suppressed. Since
many insect species are capable of moving great distances, the full effect of the
technique can probably only be fully demonstrated on isolated populations unless the
migration of native insects Into the experimental areas can be greatly reduced or
prevented.
Sterilizing Native Populations
If chemical sterilants could be used to sterilize insects In a native population, the
expense of mass rearing and releases would be eliminated and the sterilized insects
would remain In the population to compete sexually with unsterilized native insects.
This latter effect would be a bonus and would further reduce the reproductive potential
of the native population. For example, if an insecticide kills 90 of 100 insects f
each sex in a population, 10 pairs will remain to mate and produce the next generation.
If a sterilizing agent renders 90 of iao insects of each sex In a population incapable
of reproduction, the 10 males that avoided the sterllant compete in mating for the 10
remaining females with the 90 sterilized males. We would expect only 1 fertile mating
to result from this combination. Moreover, the sterilized population would compete in
time and space in the insects’ ecosystem 9 . The use of chemosterilants with various
baits and attractants appears a promising method of inducing sterility in native insect
populations.
Knipling and McGuirelO developed seven hypothetical population models to evaluate the
potential of sex attractants in Insect control programs. Essentially, their findings
indicated that: (a) a trapping or appropriate system of treatment in which the ratio
of the equivalents of the competing sex attractant (synthetic, extract, or caged virgin
females) to the number of wild females in the population was high would greatly reduce
the probability of native male matings; (b) the total impact of the system of treatment
on the reproductive potential of the population would not be affected by the number of
matings attempted by males but would increase if females were attracted to male attrac—
tants and attempted multiple matings before oviposition; (c) killing the attracted
males would be only slightly less effective than sterilizing them; and (d) the most
efficient system of sterilizing a native population would be realized if both sexes
were attracted and sterilized. The authors ‘also indicated that releases of sterile
males combined with the use of baited chemicals (sex attractants) that would kill or
sterilize the native males would substantially increase the degree of population con-
trol. In addition, they showed that theoretically the use of a given number of caged
virgin female insects as sex attractants would be as effective as the release of the
same number of sterile males; also, they would achieve the same increasing degree of
effectiveness as the native population declined as would releases of sterile Insects.
The theoretical considerations are challenging, and the tremendous potential of inte-
grated methods of inducing sterility deserve extensive consideration by researchers to
evaluate their merit.
Sterility methods have been shown to have a high degree of potential for many economic
Insect species. For example, the potential of the method was demonstrated with the
codling moth, Carpocapsa pomonella (L.), in limited field trials 1 ’ 12 . In a test in
1966, chemically sterilized codling moth males were released by the USDA Entomology
Research Division in a 15-acre apple orchard at Yakima, Washington. The results were
promising and the control obtained was as good as that obtained in orchards treated
with the regular schedule of insecticidal sprays. In addition, the absence of the
sprays permitted the natural predators and parasites to provide effective control of

-------
41
the European red mite, Panonychus ulmi (Koch), and the wooly apple aphid, Eriosoma
lanigerum (Mausmann). Similar results were obtained with releases of irradiated
codling moths in Canada in 1966 and at Yakima in 1967 in a 93—acre apple orchard (Butt,
personal communication).
Before area—wide population control of the codling moth by the method of sterile insect
release can be proved feasible and practical, a large—scale pilot program involving
several thousand or more acres must be conducted. Such a project would bridge the gap
between exploratory research and practical application.
The development of techniques of controlling insect populations by the method of sterile
insect releases over large areas is a tremendous undertaking. The talents of many
scientific disciplines are involved, and the most detailed and exacting information
concerning rearing, biology, ecology, behavior, and population dynamics of the subject
species is required. However, when the procedure is successfully developed and imple-
mented, it can substantially reduce insect losses and the costs of control and can
avoid the introduction of damaging side effects into our environment.
Biological Control
Biological control agents are the most important factors in regulating natural popula-
tions of noxious insects. More than 1,100 viruses, bacteria, fungi, protozoa, ricket—
tsia, and nematodes attack insects in.their environment 13 . Viruses attack eighteen
or more important crop pests such as the corn earworm, Heliothis zea (Boddie), the
cabbage looper, Trichoplusia ni (Hubner), the tobacco budworm, H. virescens (F.), and
the armyworm, Pseudaletia unipuncta (Haworth).
Spectacular results were obtained when viruses were used to control certain forest
insect pests 14 , and a bacterial pathogen, Bacillus popillae Dutky, that attacks
Japanese beetles, Popillia japonica Newman, provides good control of this insect - 5
when it is applied as a spore dust to turf. Another bacterium, Bacillus thuringiensis
var. thuringiensis Berliner, is pathogenic to about 110 species of Lepidoptera and 8
species of Diptera 16 and is recommended for control of cabbage loopers, alfalfa cater-
pillars, Colias eurytheme Boisduval, and the tobacco hornworm, Manduca sexta (L.).
A number of formulations or varieties of Bacillus thuringiensis have been tested for
insect control. A strain has been found which, under laboratory conditions, is about
100 times more effective than strains commercially available against the bollworm on
cotton and against other insect pests l 7 ’. The effectiveness of this new strain, referred
to as l ID—i, must be determined under field conditions before its practical value can
be appraised. However, field studies to date are most promising. Other field studies
have shown that a polyhedrosis virus for control of cabbage looper is just as effective
and economical as insecticides. Another polyhedrosis virus has sometimes afforded the
same high degree of control of the cotton boliworm. Variations in test results with
Insect viruses are believed to be due to the way In which they have been formulated,
and efforts are being made by Industry to develop improved and more stable formulations.
Like chemical pesticides, much toxicological data will be required to prove the safety
of an insect virus before it will be registered and receive approval for use.
Control of agricultural pests by parasites and predators has also had some marked
successes 18 . One aspect of the use of insect parasites and predators for insect con-
trol involves exploration, introduction, evaluation, distribution, and establishment
so that they will become a part of the environment and contribute to the control of
destructive insect pests. Another aspect is to protect native beneficial insects
which play a very important role in regulating destructive pest populations. Attempts
have been made to introduce parasites and predators of about 80 pests into the U.S.
over a span of more than 80 years 19 ’ 20 . Of about 520 species that have been imported,
115 have become established, but only about 20 have provided important control of some
of our worst pests. Introductions of beneficial insects have proved quite useful
against several scale insects, the European corn borer, gypsy moth(Porthetriadisparl(L.)),

-------
42
alfalfa weevil ( Hypera postica (Gyllenhal)), Rhodes—grass scale ( Antonina
£ ! ! !1 ! (Maskell)), and others. One approach that deserves considerable attention
is the possibility of mass rearing insect parasites and predators for sustained
release to supplement the native forms in the environment.
The possibility is now being investigated in the Blue Mountain area of Washington
where large acreages of canning peas are grown and pea aphids, Acyrthosiphon pisum
(Harris), are a problem. The pests overwinter on alfalfa plants that are also reser-
voirs of pea enation and pea streak viruses, and then the alate aphid forms migrate
to peas in the spring 21 . About 100 million braconid parasites, Aphidius pulcher
Baker and 4phidius smithi Sharma and Subba Rao, were therefore reared and released in
the spring of 1966 to determine the effectiveness of these parasites in controlling
the populations of pea aphids developing on the alfalfa. Also, portable polyethylene—
covered greenhouses were developed and placed over dormant alfalfa in the winter to
protect the plants from the weather and to force growth four to six weeks ahead of the
alfalfa in the surrounding fields.
These field nurseries were then stocked with laboratory—reared pea aphids and parasites.
As the populations of parasites in the cages developed, they were allQwed to escape
through temperature—controlled automatic roof vents’ 2 . The results to date indicate
that substantial control of pea aphids on alfalfa was obtained with subsequent reduc-
tion in migrations to pea plantings. The possibility of controlling pea aphids by
this method appears promising.
Field tests have shown that two mass releases totaling 292,000 predatory aphid lion,
Crysopa carnea Stephens, eggs or larvae per acre was as effective against the bollworm
on cotton as the best available insecticides 23 .
Attractants
Insects respond positively to many chemical, biological and physical stimuli. Entomo-
logists have visualized the potential of manipulating the resulting behavioral responses
to achieve economic control of pests through trapping and killing, luring and steri-
lizing, or disrupting their mating behavior.
The most potent and pecific insect attractants appear at present to be the sex phero-
mones, and Jacobson 2 ” recently compiled a list showing that such pheromones have been
demonstrated in more than 200 insect species.
At present, we have completed the isolation, identification, and synthesizing of the
sex pheromone of only a relatively few insects. One of the most recent was that of
the cabbage looper 25 . However, while the chemists were still working to produce the
synthetic pheromone, researchers were using living female moths to investigate possible
ways of using the attractant when it was ready.
One of the first approaches was to combine living virgin female moths and a trap
equipped with a blacklight lamp which is known to attract and catch cabbage looper
moths. When the two attractants were combined to produce a baited trap, more male
insects were captured in the baited traps than in traps equipped with either ;blacklight
or virgin females alone 26 . Thus, when the breakthrough in synthesis came, investi a-
tors were ready to evaluate the potential of the synthetic pheromone in the ield 2 ’.
A ranch near Red Rock, Arizona, that includes 3,110 acres, 2,240 acres of whjich are in
crops, was selected for the test. (Annually about 1,000 acres are planted to fall
lettuce, 800 acres to spring lettuce, and 200 acres to cotton.) The install tion
of .blacklight traps baited with synthetic cabbage looper sex pheromone at t ie rate
of about one trap unit per six acres of cultivated ground was completed in March 1966.
To date, collections of female cabbage looper moths in a check area about qine miles

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43
away hate been 14 times greater and catches of male cabbage loopers have been 30 times
greater tita, n in the control lighted area. Also, though egg and larval counts have
varied cons:f4erably, fewer eggs and larvae were found on lettuce in the trapping area
compared with the check area. Thus, the results appear promising though the intensive
use of insecticides on the ranch makes it impossible to evaluate the full impact of
the baited traps.
Since 1966, research has been conducted on the island of St. Croix, U.S. Virgin Islands
to evaluate the effects of traps equipped with blacklight lamps on populations of the
tobacco hornworm. The approximately 3 traps per square mile installed on the 84—
square—mile island became operational in June 1967. However, for about 1 year before
the lights were turned on, 9 separate traps were operated to develop baseline informa-
tion on the magnitude and seasonal distribution of the populations. Also, in 1968
after Hoffman et al. 28 demonstrated that baiting light traps with virgin female horn-.
worm moths resulted in marked increases in the catch of males, all the light traps on
the island have been baited with virgin female moths.
Since the traps began operating, the populations of tobacco hornworm moths have
decreased consistently; in March 1968, they appeared to be about 30—40% as high as
the populations recorded before the experiment. Also, after the traps were baited
with virgin female moths in March 1968, the male catches increased about 6—10 times
in the baited traps compared with the catch in unbaited traps. Moreover, for about
6—8 weeks after the first baiting of the light traps, 4—5% of the females collected
in the traps were unmated. This percentage increased to about 6—10% for several months
to a peak of 30% virgin females and declined thereafter to a relatively constant rate
of 14—16% unmated females. Another indication of the effect of baited traps on
populations of male hornworms is the decrease in the percentage of males caught in
unbaited traps from a fairly constant 60% before the baiting to about 40% at the
present time. Thus, the population of tobacco hornworms on the island of St. Croix,
measured by catches in the light traps, now appears to be about 20% of that present
on the island before the beginning of the experiments (w. Cantelo and 3. Smith, per-
sonal communications). The results are in the preliminary stages of evaluation, but we
hope they will provide us with some answers about how light traps can fit into programs
for control of hornworms.
The possible use of sex pheromones in preventing orientation or through mating
inhibition is also an exciting new concept.
One phenomena that has been observed by investigators studying male behavior after
stimulation by sex pheromones is adaptation or attenuation of response after prior
conditioning stimulus. The threshold concentration of pheromone necessary to induce
response is raised for a time following the period of exposure. Cabbage looper males
may not respond to a given threshold concentration for several hours after first
exposure to the pheromone 29 ’ 30 .
Many investigators have proposed that if high enough concentrations of pheromone were
maintained over large areas, native females could not contribute enough additional
pheromone to result in orientation to them and males would never locate females to
inseminate them. Under field conditions a concentration of 1xl0 ° gfliter completely
prevented orientation of males to pheromone—emitting females 3 l.
The potential of an attractant combined with a toxicant to provide low—cost control
of a pest over a large area was demonstrated when the oriental fruit fly, Dacus
dorsalis Hendel, was eradicated on the island of-Rota 32 . Methyl eugenol, a powerful
male attractant, was combined with 1% naled and impregnated in cane—fiber squares.
The squares were dropped from aircraft flight lanes about five miles apart, except
for inhabited areas where bait stations were used. Daily monitoring with traps showed
an immediate 93% reduction in fly populations. After 10 drops, no flies were captured
and none have been found during the 24 subsequent months of trapping and inspecting
of host fruits. Only 3.5 grams of toxicant/acre were required for the entire program.

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Repellent Techniques
Although great progress in insect control has been made with insecticides, these
killing agents do not prevent viruliferous insects from infecting crop plants; such
vectors must be killed almost instantly or prevented from feeding.
Numerous inve tiptors have observed and reported on the response of aphids to color
and 1ight 33 ’ 3 ’ 3 ’. Also, the repellent effect of aluminum foil on insects was first
observed in 1949 bx Lester Wall, Reynolds Metal Co., Richmond, Virginia (unpublished
report), and Kring 6 reported that when unpainted aluminum pans were placed around
yellow pan traps, aphids avoided the yellow pan traps. Smith 37 therefore began tests
in 1963 at Beltsville, Maryland to determine whether this phenomena could be used to
repel flying aphids and reduce incidence of viral infections in crops.
In one test in 1965, 50% of the soil area of each field plot of bush squash at
Beltsville, Maryland was covered, with sheet aluminum foil. Other plots were untreated
or sprayed with an effective aphicide. The presence of the aluminum sheets reduced
the catch of aphids by more than 95% compared with the catch in unmulched check plots
and in plots sprayed with an insecticide during a 3—day period of heavy aphid flight.
Also,tthe number of infected plants in the mulched plots was greatly reduced for
6 to 7 weeks compared with virus infected plants in the sprayed and untreated plots,
and the yields of squash in the mulched plots were 6 times greater 38 .
In another test at Long Island, New York, mulches of reflective aluminum and also of
white plastic reduced catches of winged aphids in yellow pan traps by more than 87%
and decreased the spread of cucumber mosaic virus in gladiolus plantings 39 . Other
researchers who have used such a mulch have reported reduction of lettuce mosaic in
lettuce plots 40 and protection of roses from flower thrips, Frank].iniella tritici
(Fitch , injury 41 . Aluminum mulches have not been effective with all aphids on all
crops 4 ,43; however, reflective mulches with plastic or paper backing can be produced
to a wide range of specifications, and growers of some commercial crops are trying such
mulches to warm the soil early and to achieve control of weeds and aphids.
Insect Hormones
Another recent trend is research on insect hormones and hormonelike materials that
disrupt insect development rather than to cause immediate death. Sterility in adult
insects may result soon after treatment with molting hormones or their analogs, whereas
juvenile hormones act by interrupting insect development and in some cases produce
monster insects that finally die or, should ‘they attain adulthood, cannot reproduce
because of their physical abnormalities 44 . Some of these hormonal materials, which
would not be expected to have a detrimental effect on nontarget organisms, are effective
against test insects at small dosage rates, about 1 nanogram or one—billionth of a
gram. New “hybrid” synthetic ethers, which are juvenile—hormonelike materials, have
been found to block normal insect growth and development. These compounds, some of
which are fairly easy to synthesize, often show greater potency than the insects’ own
hormones or biologically similar synthetic compounds previously tested 45 .
Cultural Techniques
In the Pacific Northwest, the green peach aphid is also the most important vector of
beet western yellows and beet yellows viruses, diseases that cause annual losses of as
much as 25 to 30% of the yield of sugarbeets 4 °. Also, unfortunately, beet western
yellows, the most prevalent of the yellows diseases there, can be harbored by 30 or
more hosts other than beets which serve as reservoirs of the virus 47 As noted, the

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45
green peach aphid overwinters primarily in the egg stage on peach trees in the general
area, but small numbers of the summer forms overwinter and feed on plants growing
year—round in protected places, and intensive ecological studies made between 1962
and 1964 showed that many of these overwintering hosts of the summer aphid forms were
also alternate hosts of beet western yellows virus 48 ’ 49• Also, warm spring—fed
drainage ditches in sugarbeet—growing areas near Toppenish, Washington proved to pro-
vide a micro—climate 20—50°F. warmer than the surrounding environment where the weeds
and aphids could fluorish throughout the year. Thus, though aphids from eggs over—
wintered on peach trees are free of virus until they feed on diseased plants, the
summer aphid forms that overwinter on infected weeds carry the virus to young sugarbeet
plants when they migrate to them in the spring.
These findings stimulated studies to determine whether eliminating overwintering popu—
lations of aphids and weed hosts from drainage ditches would reduce viral infections
in nearby sugarbeet fields. A 22— and a 30—square—mile area southwest of Toppenish,
Washington that contained 42 to 53 miles of drainage ditches were the test areas; a
similar area 4 miles east of the experimental area served as a check. During January,
February, and March 1965—1967, before sugarbeets began growing and aphids began
migrating, the weeds in the drainage ditches in the test area were destroyed by
burning. In 1966, 91% fewer aphids and 76% fewer diseased plants were found in the
area where the ditches were burned than in the unburned check areas; in 1967, 75% fewer
diseased plants were found in the burned area than in the unburned check area. The
increased yield in the test area was estimated at more than 2 tons per acre, and the
cost of ditch burning per acre of sugarbeets protected ranged from $2.20 to $6.85 and
averaged $4.00 for the three years. This cost compares favorably with the average
estimated cost of $16.00 per acre for conventional chemical sprays.
The results of this research have been received enthusiastically by the sugarbeet—
growing industry and the individual growers in the area, and they have now contracted
to have the ditch burning done on a routine basis as part of their regular process of
insect control.
Another example of the method of host elimination or replacement to reduce an insect
population concerns the beet leafhopper, Circulifer tenellus (Baker), in Idaho. This
insect is the sole known vector of curly top virus in the United States, and the
large desert and range areas in southern Idaho where weed—host plants (several species
of broad—leaved annual plants) have become established and serve as overwintering and
spring hosts. (Russian thistle is the most important summer host.) Scientists
recognized that the breeding areas proper might be the vulnerable link in the host—
plant cycle and postulated that if it were broken, effective control of the insect
could be obtained. (The acreage of Russian thistle is smaller than that of annual
weed hosts and appeared more vulnerable to control.)
The Bureau of Land Management, Department of the Interior, therefore began seeding the
summer breeding areas of the beet leafhopper in Idaho in 1959 with crested wheatgrass,
Agropyron cristatum (L.) Gaertn. The cost per acre of this seeding ranges from
$3.25 to $6.00 per acre depending on the method used. Also, the Plant Pest Control
and Entomology Research Divisions, Agricultural Research Service, U.S. Department of
Agriculture, and the Idaho Bean Commission have cooperated in advisory capacities.
Since the program began permanent crested wheatgrass has been seeded over more than
200,000 acres of range 5 ” .
Before the seeding program began, curly top virus caused losses in sugarbeet yields
of as much as 65%. Also, the beet leafhopper transmitted the virus to beans, tomatoes,
and other agriculturally important crops. Since the initiation of the program, the
situation has changed remarkably. Curly top has been reduced to a minor problem, and
the establishment of crested wheatgrass has increased the carrying capacity of range

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46
for annual grazing tenfold, in addition to increasing the dependability of available
range forage and reducing the hazards of grass fires and wind erosion 5 . Thus, the
outcome is a fine demonstration of an effective, economical, and efficient method of
controlling an insect through the application of many scientific disciplines to the
solution of a common problem.
Integrated Control
Integrated control is a system designed to use all available, suitable, and necessary
methods of controlling insects to reduce pest populations and maintain them at levels
below economic thresholds. The development of integrated control systems are based
on exacting and definitive information on the biology, ecology and population dynamics
of the pest species in the complex agro—ecosystem being considered. Although literally
hundreds of insects may occur, there are usually 1 or 2 major insect pests which cause
economic damage. These are the key species which must be controlled with minimum or
no effects on the other complex components of the ecosystem and their interactions.
Pickett and McPhee 52 were among the first to recognize the adverse effects of the
unilateral chemical approach to ordered pest control and they developed valid princi-
ples for an integrated control program which has provided guidelines and influenced
the direction of subsequent research.
The majority of entomologists recognize the mistakes of the past. Recognizing the
variety of methods of insect control now available, it is imperative that all consid-
eration be given to developing logical, effective and efficient systems through
combinations of these methods. Thus, we can bring maximum pressure on pest insect
populations while minimizing the impact on the entire agro—ecosystem.
SuimnRry
Research designed to develop and exploit alternative nonchemical methods of insect
control demand the most exacting and sophisticated information on insect biology,
behavior, movement, ecology, and population dynamics. The focus of research must be
directed at an entire key insect population, or a large segment of it, since these
methods are designed to suppress or reduce the insect population to a level below its
economic threshold. Many insect species are capable of moving great distances and
methods designed to reduce such populations in local or very limited areas have a low
probability of success because insects migrating from great distances often prevent
successful reductions of the total population in the management area.
In recent years there have been a number of significant successes in the application
of nonchemical methods for insect control.. However, no one method appears to be
adequate to solve all insect problems or even, in many cases, the same insect problem
under different ecological conditions. In many cases, there may not be a single
method which will accomplish effective control but a combination of methods which are
logically and effectively integrated may be required to bring maximum pressure on an
insect population.

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47
References
1. Hoffmann, C. H. 1970. Alternatives to conventional insecticides for control
of insect pests. Agric. Chem. 25: 14—9.
2. Painter, R. H. 1951. Insect resistance in crop plants. MacMillan Pubi. Co.,
New York, 520 Pp.
3. Luginbill, P. 1969. Developing resistant plants. The ideal method of con-
trolling insects. USDA Prod. Res. Rept. ill, 14 pp.
4. Baumhover, A. H., A. J. Graham, B. A. Bitter, D. Hopkins, W. D. New, F. H. Dudley,
and R. C. Bushland. 1955. Screw—worm control through release of sterilized
flies. J. Econ. Entomol. 48: 462—8.
5. Baumhover, A. H. 1966. Eradication of the screw—worm fly, an agent of myiasis.
J. Amer. Med. Assoc. 196:240—8.
6. Knipling, E. F. 1960. The eradication of the screw—worm fly. Sd. Amer.
203: 54—61.
7. LaBrecque, G. C. 1961. Studies with three alkylating agents as house fly
sterilants. J. Econ. Entomol. 54: 684—9.
8. Knipling, E. F. 1964. The potential role of the sterility method for insect
population control with special reference to combining this method with conven-
tional methods. USDA ARS 33—98, 54 Pp.
9. Knipling, E. F. 1962. Potentialities and progress in the development of
chemosterilants for insect control. J. Econ. Entomol. 55: 782—6.
10. Knipling, E. F., and J. U. McGuire, Jr. 1966. Population models to test
theoretical effects of sex attractants used for insect control. USDA Agr.
Infor. Bull. 308, 20 pp.
11. Hathaway, D. 0., and B. A. Butt. 1966. The sterility approach to insect
control. Trans. 72nd Annu. Mtg. Idaho State Hort. Soc., p. 28—34.
12. Proverbs, M. D., J. R. Newton, and D. M. Logan. 1966. Orchard assessment of
the sterile male technique for control of the codling moth, Carpocapsa pomonella
(L.) (Lepidoptera:O1ethreutidae). Canad. Entomol. 98: 90—5.
13. Steinhaus, E. A. 1960. Insect pathology: Challenge, achievement, and promise.
Bull. Entomol. Soc. Amer. 6: 9—16.
14. Cameron, J. V. M. 1963. Factors affecting the use of microbial pathogens in
insect control. Annu. Rev. Entomol. 8: 265—86.
15. Polevka, J. B. 1956. Effectiveness of milky disease in controlling Japanese
beetle in Ohio. J. Econ. Entomol. 49: 4—6.
16. Heimpel, A. M. 1963. The status of Bacillus thuringiensis . In New Approac1 es
to Pest Control and Eradication. Adv. in Chem. Series 41, p. 64—74.

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48
17. Dulmage, H. T. 1970. Insecticidal activity of lID—i, a new isolate of Bacillus
thuringiensis var. alesti . J. Invert. Pathol. 15: 232—239.
18. Clausen, C. P. 1958. Biological control of Insect pests. Annu. Rev. Entouiol.
3: 291—310.
19. Clausen, C. P. 1956. Biological control of Insect pests in the continental
United States. USDA Tech. Bull. 1139, 151 pp.
20. DeBach, P., and E. I. Schlinger. 1964. (Ed.) Biological Control of Insect Pests
and Weeds. Reinhold Pubi. Corp., New York, 844 pp.
21. Cook, W. C. 1962. Ecology of the pea aphid In the Blue Mountain area of
eastern Washington. USDA Tech. Bull. 1287, 48 pp.
22. Halfhill, J. E., and P. E. Featherstone. 1967. Propagation of braconid parasites
of the pea aphid. J. Econ. Entomol. 60: 1756.
23. Rldgway, R. L., and S. L. Jones. 1969. Inundative releases of Chrysopa carnea
for control of Heliothis on cotton. J. Econ. Entomol. 62: 177—80.
24, Jacobson, M. 1965. Insect sex attractants. Interscience Publ., New York, 154 pp.
25. Berger, R. S. 1966. Isolation, identification, and synthesis of the sex
attractant of the cabbage looper, Trichoplusia ni. Ann. Entomol. Soc. Amer.
59: 767—71.
26. Henneberry, T. J., and A. F. Howland. 1966. Response of male cabbage loopers
to blacklight with or without the presence of the female sex pheromone.
J. Econ. Entomol. 59: 623—6.
27. Wolf, W. W., J. G. Hartsock, J. H. Ford, T. J. Henneberry, 0. A. Hills, and
J. V. Deboit. 1969. Combined use of sex pheromone and electric traps for
cabbage looper control. Trans. ASAE 12: 329—31, 35.
28. Hoffman, J. D., F. R. Lawson, and Braxton Peace. 1966. Attraction of black-
light traps baited with virgin female tobacco hornworm moths. J. Econ.
Entomol. 59: 809—11.
29. Ignoffo, C. M., R. S. Berger, H. M. Graham, and D. F. Martin. 1963. Sex
attractant of cabbage looper, Trichoplusla ni (Hubner). Science 141: 902—3.
30. Shorey, H. H. 1964. Sex pheromones of noctuid moths. II. Mating behavior of
Trichoplusia iii (Lepidoptera:Noctuidae) with special reference to the role of
the sex pheromone. Ann. Entomol. Soc. Amer. 57: 371—7.
31. Gaston, L. K., H. H. Shorey, and C. A. Saario. 1967. Insect population control
by use of sex pheromones to Inhibit orientation between the sexes.
Nature 213: 1155.
32. Steiner, L. F., V. C. Mitchell, E. J. Harris, T. T. Kozuma, and M. S. Fujimoto.
1965. Oriental fruit fly eradication by male annihilation. J. Econ. Entomol.
58: 961—4.

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33. Broadbent, L. 1948. Aphis migration and the efficiency of the trapping
method. Ann. Appi. Biol. 35: 379—94.
34. Moericke, V. 1950. Uber das Farbschen der Pflrslcht Blattlaus ( Myzodes
persicae Sulz.). Tierpsychol. 265—74.
35. Cartier, J. J. 1966. Aphid responses to colors in artificial rearings. Bull.
Entomol. Soc. Amer. 12: 378—80.
36. Kring, J. B. 1964. New ways to repel aphids. Frontiers of Sci. 17: 6—7.
37. Smith, F. F. 1965. The role of color and reflected light in trapping and
repelling transient aphids and reducing their transmission of virus diseases.
Rept. Conf. Relationship Between Arthropods and Plant Pathogenic Viruses.
U. S.—Japan Sci. Coop. Program (Supplement) Tokyo, pp. 62—70.
38. Smith, F. F., and R. Webb. 1968. Repelling aphids by reflective surfaces, a
new approach to the control of insect transmitted viruses. Proc. 8th Nat’l.
Agr. Plastics Conf., pp. 89—97.
39. Johnson, C. V., A. Bing, and F.F. Smith. 1967. Reflective surfaces used to
repel dispersing aphids and reduce spread of aphid—borne cucumber mosaic virus
in gladiolus plantings. J. Econ. Entomol. 60: 16—8.
40. Heinze, Von Kurt. 1967. Folienversuche mit salat zur Abschreckung von
virusubertragenden Blattlausen. Nachrbl. Deut. Pflanzenschutzdienstes 19: 150—3.
41. Ota, A. K., and F. F. Smith. 1968. Aluminum foil thrips.repellent. Amer.
Rose Ann. 53: 135—9.
42. Dickson, R. C., and E. F. Laird. 1966. Aluminum foil to protect melons from
watermelon mosaic virus. Plant Die. Reptr. 50: 305.
43. Rothinan, G. 1967. Aluminum foil fails to protect winter oats from aphid
vectors of barley yellow dwarf virus. Plant Dig. Reptr. 51: 354—5.
44. Williams, C. M., and W. E. Robbins. 1968. Conference on Insect—Plant Inter-
actions. Bioscience 18: 791—2, 797—9.
45. Bowers, W.. S. 1969. Juvenile hormone: Activity of aromatic terpenoid ethers.
Science 164: 323—5.
46. Wallis, R. L. 1967. Yield of sugarbeets in Pacific Northwest reduced by yellows
viruses transmitted by green peach aphids. J. Econ. Entomol. 60: 328—30.
47. Wallis, R. L. 1967. Green peach aphids and the spread of beet western yellows
virus in the Northwest. J. Econ. Entomol. 60: 313—5.
48. Wallis, R. L. 1965. Host elimination experiment for suppression of the green
peach aphid and “yellows” on sugarbeets. Proc. Wash. State Entomol. Soc.
20: 170—1.
49. Wallis, R. L. 1967. Some host plants of the green peach aphid and beet western
yellows virus in the Pacific Northwest. J. Econ. Entomol. 60: 904—7.

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50. Douglass, J. R., and W. C. Cook. 1954. The Beet Leafhopper. USDA Circ. 942,
21 pp.
51. Gibson, K. E., and J. T. Fallini. 1963. Beet leafhopper control In southern
Idaho by seeding breeding areas to range grass. USDA ARS 33—83, 5 pp.
52. Pickett, A. D., and A. W. McPhee. 1965. Twenty years experience with Integra-
ted control programmes In Nova Scotia apple and pear orchards. Proc. 12th
mt. Congr. Entomol., p. 597.

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THE DIAGNOSIS AND TREATMENT OF ACUTE
PESTICIDE POISONING CASES
C. A. Reich, M.D., M.P.H.
Pesticide poisoning is reported by the National Clearinghouse for Poison
Control Centers at about 5,000—6,000, cases per year. This represents, for the
most part, accidental poisoning among children. Many more cases than this
occur,eapectaily among pesticide exposed workers, but there are few reports
of these. The fatality rate in pesticide poisoning is considerably higher
than that seen with the more common agents in poisoning such as aspirin,
tranquilizers, and birth control pills.
The incidence of pesticide poisoning varies a great deal from region
to region in the U.S.A., being highest in agricultural areas and in urban
centers surrounded by agricultural areas.
Poisoning at times occurs on a mass scale when flour, sugar, or the
like, become contaminated with pesticides in transit or in storage, since
pesticides survive the cooking and baking processes quite well. Examples of
these are the food poisoning episodes of recent years in the Middle East,
Columbia, and Mexico. Episodes on a much smaller scale have occurred in
the U.S.A.
The Community Studies have been conducting prospective epidemiological
studies of workers exposed to pesticides to determine If their health is
being adversely affected, In addition to this, our Studies provide diagnostic
and therapeutic assistance in their local areas to Doctors handling cases of
acute poisoning. Most of our reports to date have come from south Texas and
§outh Florida which represent primarily cases of individual poisoning but
at times are of group poisoning.
In south Texas, the incidence of poisoning increased for several years, then
declined only to rise again. Most cases occurred in June and July during
the period of greatest pesticide use. Most cases were among teen—agers
and young adults who were employed by farmers and spray pilots to assist in
mixing and applying pesticides.’ Parathion and methyl parathion were the
usual agents, and the route of exposure was almost always dermal. Very few
deaths occurred, even though pesticides are by far and away the leading
cause of poisoning in .this area.
The signs and symptoms observed in these cases indicate that a variety of
biochemical and physiological functions are altered by pesticides. The
central nervous system, cardiovascular system, gastrointestinal system, and
musculoskeletal system are the most obviously affected in pesticide poisoning.
The diagnosis may be difficult, because of this variety of signs and symptoms
which are suggestive of other conditions as well as pesticide poisoning.

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In south Florida, poisoning reflects three sorts of circumstances:
(1) accidental ingestion by 1 to 2 year old children in and around the house;
(2) accidental derinal exposure in occupational exposed workers; and
(3) suicidal ingestion in middle—aged to older adults. Numerous pesticides
have caused deaths in this area, ranging from old types like Paris Green
up to newer pesticides like gectran. In Florida, pesticide poisoning
is a year round phenomenon rather than coinciding with the season of
greatest agricultural use of pesticides. This is due to the importance
of the accidental cases among children and the suicidal cases among adults.
The highest death rates are among adults, but this represents the fact
that such a large proportion of these are suicidal. The agents of most
importance are the organophosphates, especially parathion, but numerous
compounds singly or in combination have been involved. There have been
several homicidal attempts with pesticides too, most of which have been
successful. In this area, the leading cause of death from poisoning
among children is pesticides.
How important pesticide poisoning is in your area will depend upon
several factors already noted. Determining what the true incidence is
in any particular area may be difficult, because of errors in diagnosis
and the lack of an effective system of reporting. Such poisoning is,
however, preventable —— though suicidal cases present particular problems.
When one considers that only about 10% of the true incidence of poisoning
in the U.S.A. is reported, and that the Poison Control Centers report over
100,000 cases per year, it is apparent that poisoning (not just with
pesticides) represents an important public health problem.

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CHRONIC BIOLOGIC HAZARDS OF PESTICIDES
MUTAGENES IS
Stanley Glenn
Mutagenesis deals with the capability of producing genetic damage.
When genetic damage occurs, the burden of hereditary defects in
future generations is increased. One potential genetic hazard
comes from pesticides; however, the overwhelming majority have
not been adequately tested, although appropriate techniques and
methods are now available.
The word mutation is used to designate any inherited change in the
genetic material. It may be a chemical transformation of an
individual gene that causes it to have an altered function, or
the change may involve a rearrangement, or a gain or loss, of
parts of a chromosome. This kind of change is often visible by
ordinary microscopy. Mutations may occur anywhere in the body,
and frequently the result is the death of the cell involved. A
mutation that is transmitted via the sperm or egg to the next
generation can affect every cell in the body of the descendent
individual, with consequences that can be disastrous.
What kinds of effects on the human being do mutations produce?
The most important fact to emphasize is that there is no single
effect, for the range of effects produced by gene alterations includes
every type of structure and process. At one extreme are consequences
so severe that the individual cannot survive, so-called lethal effects.
If death occurs early in embryonic development, it may never be
detected. If death is at a later stage, it may lead to a miscarriage.
Roughly one-fourth of spontaneous abortions show a detectable
chromosome aberration. If the embryo survives until birth, there may
be physical abnormalities. There are hundreds of known inherited
diseases and probably many more that are unknown, all of which owe
their ultimate cause to mutations.
At the other extreme are genes t ith mild effects, and those with
smaller effects finally become imperceptible.
Some mutant genes are dominant, in which case the abnormality or
disease will appear in the very next generation after the mutation
occurs. If the gene is recessive, the disease or abnormality may be
delayed for many generations until some unlucky child inherits a
mutant gene from each of his parents. What happens in the first
generation is only a fraction of the total impact of the mutation
process. If the gene causes a lethal or sterilizing effect, it will

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persist for only one generation and will affect only one person.
If it causes only a slight impairment, it may be transmitted from
generation to generation and thereby affect many people.
The first evidence in 1927 that environmental agents under human
control might have some influence on the genetic constitution of
future populations followed the discovery that high energy radiation
causes mutations. The discovery of nuclear energy brought a whole
new dimension to the problem and greatly increased public awareness
of genetic hazards. As soon as radiation-induced mutagenesis was
discovered, there were strong reasons to suspect that many chemicals
might have the same effect, but proof of this did not come until after
World War II when mustard gas was shown to induce mutations in fruit
flies. Since that time a large number of chemicals of a great
diversity of structure and activity have been shown to be mutagenic.
Pesticides are of particular concern because they are used so
widely and in such enormous amounts; they are very potent biologically...
otherwise they would not be effective pesticides.
There are approximately 55,000 pesticides on the market at the present
time made up of various combinations of 400 basic chemicals. Certain
of these pesticides have been clearly shown to have mutagenic
characteristics. Despite the extensive use of pesticides, our
information on their possible mutagenicity is grossly inadequate.
Several have been tested in various test systems, but the Mrak
Committee believes that none have had the kind of testing that would
be regarded as adequate. An important area is the effects of exposure
to combinations of compounds. The possibility of pesticides
potentiating other pesticides or other chemical agents to become
mutagens has not been explored.
A variety of test methods are available, and the mammalian test systems
have the greatest relevance to human problems. In addition to the
test procedures, human population monitoring may reveal mutagenic
effects of pesticides or any other environmental agents that have
escaped detection. The task of setting up a system of population
monitoring would be terribly difficult; the damage caused by mutations
occurs in future generations, not in this one, so the effect would not
be observed for some time.
For the present, we have to accept the fact that any feasible system of
monitoring the human population could detect only a very gross effect.
As far as predicting mutagenesis is concerned, chemical structure can
be a useful guide. For example, many alkylating chemosterilants could
have been predicted to be mutagenic in advance of actual tests. If

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priorities are needed in testing, those pesticides that are used
in the largest amounts should be placed at the top of the list, with
the greatest emphasis on those used domestically and on food crops.
Particular attention should be directed to domestic exposure by
inhalation of pesticide aerosols and vaporizing pesticide strips.
Literature dealing with mutagenicity of pesticides comprises more
than 500 papers. Captan has been tested and found to be mutagenic
by a variety of techniques. Preliminary studies by Legator (1970)
indicated that p,p’ DDT is capable of inducing dominant lethal
mutations in rats. Palmer et al (1970), using tissue cultures of
rat-kangaroo cells, found that the p,p’ forms of DDT, DDD and DDE
produced twice as many chromosome breaks as did the corresponding
o,p’ forms. Tsanebara-Maneve et al (1969) produced chromosomal
aberrations with the organophosphate diazinon in human lymphocytes
in culture.
Mutagenicity is becoming increasingly important to humans as life
expectancy is lengthened through control of parasitic and bacterial
diseases, morbidity from genetic weaknesses caused by mutation is
increasing. Mutational effects may continue for many generations
after the mutation has occurred.
Genetic impairments already account for a very large part of our
existing burden of disease and premature death. If proper weight
is given to the genetic component of many common diseases, we can
calculate that at least 25% of our health burden is of genetic
origin. This figure is a very conservative estimate in view of
the genetic component of such griefs as schizophrenia, diabetes,
atherosclerosis, mental retardation, early senility, and childhood
malformations. With the reduction in morbidity of infectious
diseases, there will be an ii icreased percentage of health effects
due to genetic causes, until they approach the level of accident-
induced traumas.

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REFERENCES
Epstein, Samuel S. and Legator, M.S. - Mutagenicity of Pesticides.
Concepts and Evaluation. MIT Press. 1971.
Krause, David H. - The Cytological Effects of Pesticides on Human
Chromosomes. Masters Thesis. Michigan State University. 1970.
Report of the Secretary’s Commission on Pesticides and Their
Relationship to Environmental Health. U.S. Department of Health,
Education, and Welfare. 1969.
Williams, Clara H. - Teratology and Mutagenicity of Pesticides.
Proceedings of the Training Course: Pesticides and Public
Health (Advanced). 1970.

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57
CI (RON C BIOLOGIC HAZARDS OF PESTICIDES
TERATOLOGY
Burton R. Evans
Introduction
Teratology is the study of congenital malformations. These
malformations or abnormalities occur in live fetuses, and practically
all such effects occur during embryonic organ development.
The magnitude of teratogenesis or congenital malformations should
be put into proper perspective. It presents obviouS personal,
financial, medical and social stress on the individual and the
community. “One-third of the beds in children’s hospitals today
are occupied by individuals with congenital defects... One survey
indicates that 4 to 7.5 percent of human deliveries yield offspring
that have developmental defects which will interfere with survival
or result in clinical disease within the first year of life.” 3
Early attempts to explain congenital malformations varied and are
still heard today. There is the “Wrath of God”--or you are being
punished for doing something wrong, or the mother’s mental impressions
during pregnancy would have some influence on the child’s development.
As late as 1965 there was a report of the execution in a Near East
country of a mother for producing a child with a well developed-tail.
She was charged with consorting with a monkey! 2
The science of experimental mammalian teratology began in the 1930’s.
Malformations were experimentally produced in animals by x-rays and
Vitamin A deficiency. Rubella was identified as a teratogen in 1941.2
The famous thalidomide disaster of the early 1960’s accelerated the
interest in the teratology of drugs. In 1968 the so-called “Bionetics”
screening study which investigated the teratogenic potential of a
number of widely used pesticides stimulated investigations in this area.
In 1969-70 discovery of high levels of methyl mercury in fish of the
American rivers, bays, and lakes spurred interest in the teratogenic
effects of this compound. The Japanese had had this .problem during the
years of 1953-58 (Minatiata Bay disease) and in 1964-65 (Niigata disease). 1
Problems in Teratology Research
Since the thalidomide episode, teratogenicity testing has been required
before approval for use of a new drug is given by FDA. Since testing
can not obviously be done on man, this raises practical problems as
to the test animal. Unfortunately, no other animal parallels the
teratogenic response observed in humans. For example, cortisone
and thalidomide will cause malformations in the humans as well as
the mouse, but have no effect on several strains of rats. On the
other hand, substances in wide use by humans, such as adrenalin,
insulin, salicylates and certain antibiotics, are all known to
cause teratogenesis in laboratory animals but not In humans. Despite
those problems, the rat, rabbit, hamster and mouse are the most
common test animals used. Extrapolation from animal to man is always
a problem. In practice, the usual teratogenic agents (x-rays, German
measles, thalidomide and mercury) were each recognized by an alert medical
practitioner who observed a cluster of unusual cases and traced the
cause to its sOurce.”

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In determining a teratogenic effect, the time of administration, the
route of administration, the dose level, the number of doses and the
presence of additional stress (i.e., nutritional deficiency) and the
species used in the test animal all play a role. For example, the
most susceptible period is when the germ layers are forming, in humans
this is in the first three months of pregnancy. It is, therefore, obvious
that by adjusting one or more of these factors, teratogenesis could
theoretically be produced with almost any substance. 4
Interactions in Teratology
Malformations may be caused by genetic or chromosomal aberrations
and be inherited in some families, such as cleft palate, clubfoot, etc.
Nutritional deficiencies are known to cause some abnormalities, such as
a lack or inability to use Vitamin D induces embryonic rickets. Lack
of iodine, or its excess, may cause brain damage. X-rays are known to
produce congenital malformations. The potential danger from such as
thalidomide, are well known.
Pesticides and Other Chemicals
Within the last two years the teratogenicity of pesticides has
evoked interest because of the screening study, carried out by Bionetics
Research Laboratories under a contract for the National Cancer Institute
(58) which involved a number of widely used pesticides and fungicides.
The work of this laboratory, plus the work of many other researchers
have shown that under certain conditions a few pesticides will cause
teratogenic effects on some animals, such as paraquat in hats (costal
cartilage malformations), and carbaryl in the guinea pig. Particular
attention has centered upon the chiorophenoxy compound 2,4,5-T
because of its widespread military use as a defoliant in Viet Nam.
Recent findings with the herbicide 2,4,5-T have shown the
teratogenicity of this substance is due to in part to a contaminant,
tudioxin.1u 4 Abnormal fetuses (cleft palate and cystic kidneys) were
found in two strains of mice.
Herbicides applied, Including some 2,4,5-T, to the Tonto National
Forest in 1969 near Globe, Arizona, for the control of chaparral
on 1,900 acres raised a Storm of protest from local citizens.
Deformities In the human and animal population were charged, in
addition to the loss of livestock and crops. 7 An investigating
panel consisting of scientists from the Departments of Agriculture,
Interior, HEW, National Academy of Sciences, observers from the
Office of Science and Technology and the Arizona Extension Service
concluded the herbicides were not responsible for most injury to
plants, any injury to animals, and may have been associated with one
minor case of human illness. 6
Some work has been done attempting to associate DDT residues in
females with abnormal births, but no association has been demonstrated. 4
Mercury is commonly used as a fungicide, besides many other industrial
and commercial uses. “The effects onthe offspring of mothers ingesting
mercury-contaminated fish (disease in Minamata Bay area in 1953 and in
Niigata in 1964 in Japan) aroused concern over the teratogenic effects
of mercury compounds (82). Severe neurological effects were noted in
the children although in many cases the mothers suffered no overt
symptoms. The compound responsible was methyl mercury chloride,

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which is incorporated into the flesh of the fish through the aquatic
food chain beginning with the conversion of metallic mercury 4 on river
and lake beds by anaerobic bacteria to alkyl mercury salts.”
Summary
In review, “There appears to be no conclusive evidence that the small
number of pesticides which have been studied for teratogenic potential
actually represent a hazard to humans under normal conditions of
pesticide exposure.” 4 To ban or restrict the usage of a pesticide
that has been shown to be teratogenic to animals.”at dose levels which
far exceed actual or expected exposures is unreasonable and could well
deny usage of chemicals whose benefits far outweigh risks.” 5
It is difficult to extrapolate teratologic findings in animals
to man, for man and animals differ in sensitivity to the pesticide.
it is also difficult to pinpoint malformations in human fetuses as
arising from any specific agent, particularly if a substance is a
low-incidence teratogen. There is no good epidemiological evidence
implicating pesticides in teratological toxicity in man)’ 4 However,
much more research in this area is needed.

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LITERATURE CITED
1. Williams, C.H., 1971. Teratology and Mutagencity of Pesticides,
unpublished, EPA, Chamblee, Ga.
2. Clegg, D.J., 1971. Teratology, Annual Review of Pharmacology,
11:409-424.
3. Gortatowski, M.J., 1971. Unpublished, Current concepts of pesticides
as carcinogenic and teratogenic agents, Chief, Chemistry Section,
Utah State Division of Health, Salt Lake City, Utah.
4. Durham, W.F. and C.H. Williams. Mutagenic, Teratogenic, and
Carcinogenic Properties of Pesticides, to be published in
Annual Review of Entomology, 1972, Vol. 17.
5. PresIdent’s Science Advisory Committee, March, 1971. Report on
2,4,5-T, Executive Office of the President, Office of Science and
Technology.
6. Herbicides Caused Little Damage in Arizona Area, Scientists Find,
September 21, 1970. USDA 2894-70, Washington, D.C.
7. Shoecraft, B., 1971. Sue the Bastards, Franklin Press, Phoenix,
Arizona. 460 pp.

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61
Chronic Btologtc Ftazards of Pesticides
CARC !NOGENES IS
Burton R. Evans
Introduction
Carcinogenesis is the production of malignant new growth made up of epithelial
cells that tend to infiltrate the surrounding tissues and organs. A carcinogen
is a cancer—producing substance. Viruses and a wide variety of chemical agents
have produced cancerous growth in experimental animals. A great deal of this
effort has been directed to better understanding the causes of cancerous growth
in man and,by this,prevention and treatment. One of the most important cancers
concerned with man’s health is lung cancer. Carcinoma of the bronchus, or lung
cancer, has become the most frequent form of cancer in men in the United States
and other countries, and Is increasing. In the state of Connecticut the incidence
increased from 22/100,000 in males In 1945-1949 to 46/100,000 in 1960-1962. A
similar pattern has been shown in other states.’
In 1968 about 60,000 Americans developed cancer of the lung. The incidence in
males doubled in Denmark between 1943 and 1957. There seems to be no doubt the
increase of cancer of the lung is real. While there are many causes of lung cancer,
all the evidence suggests these are environmental products of modern civilization.
Associated Carcinogens with Lung Cancer
Cigarette smoking and atmospheric pollution have been suggested as causal factors.
The most important cause identified to date has been the inhalation of tobacco
smoke. The rate of bronchial carcinoma (lung cancer) in smokers of more than
two packages of cigarettes dai y was 217/100,000 - a rate sixty times greater
than for men who never smoked. At least 21 retrospective and three prospective
investigations 3 have been carried out and in every case a correlation between
cigarettes smoked and the incidence of 1ung cancer has been found. While lung
cancer has not been reproduced in animals experimentally, it has been so
consistently associated with cigarette smoking that most workers accept it as
a causal factor. Some workers believe there is a lapse of about twenty years
between exposure to a carcinogen, such as cigarette smoke, and the development
of cancer.
Atmospheric pollution is higher in urban areas than rural ones. It seems logical
that if air pollution plays a part In the development of lung cancer, it should
be possible to demonstrate the death rate from cancer of the lung is higher in the
towns than in the country. Carcinogenic compounds have been identified in urban
air pollution. 6 Mills 7 showed twice the prevailing lung cancer incidence rates
in urban residents driving over 12,000 miles per year in urban traffic as opposed
to those living in the city not driving this amount. Several other studies
support the view that the incidence in the Industrial areas is higher than the
agricultural areas.’ For example, a higher occ irrertceof lung cancer was reported
in the bay area of San Francisco, Los Angeles, and San Diego than in the remaining
rural areas. ’ ° These types of studies involving atmospheric pollution are very
difficult to do and arrive at convincing data. It must be remembered that, unlike
an occupational hazard, atmospheric pollution affects all living in the same lo-
cality more or less in the same way, and that it is difficult to adduce co ivir Ing
evidence for its action. 8

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There have been a, large number of chemicals that have been identified as
carcinogens in animals; the effect of many of these on man in the dosages he
[ s exposed to are not known for most of them. There are certain occupations
that are exposed to large amounts of a particular substance where cancer has
been associated. Since the respiratory system becomes heavily involved in any
situation where foreign substances are suspended in the air, it is natural to
assume that the cancer involved in some occupations would be lung cancer. There
is adequate experimental and epidemiological evidence to incriminate various
organic and inorganic industry-related chemicals as causes of cancer of the lung.
This is supported by experimental investigations En which cancer of the lung has
been produced in-animals exposed to radioactive metals, nickel, chromium and
arsenic. 1 For example, occupational arsenic poisoning has been associated with
lung cancer in vine growers in Beaujolais. 5
It has become apparent that there is a risk of cancer of the lung in persons
exposed to asbestos- -not only to workers in the asbestos industry, but also
those living in the area where the industry is located. 1 Inhalation of
asbestos fibers leads to asbestosis, a fibrotic condition of the lung. The first
indication of a carcinogenic hazard in asbestos workers came from a study of
the association between this condition and lung cancer. Bonser, Faulds, and
Steward (1955)8 for example, in a series of 72 asbestosis victims, found 12
cases of carcinoma of th lung in males. The balance of evidence suggests that
asbestosis is frequently associated with lung cancer,and thus that work with
asbestos under bad conditions is liable to a higher incidence of lung cancer
than normal.
In these types of studies where you are attempting to associate some environmental
factor with lung cancer it is necessary to compare two groups of people as nearly
alike as possible with only one variable in one group associated with factor “X”
and one not associated with it. The trick then is to determine if the one
variable (factor “K’ such as cigarette smoking or asbestos) is associated with
the disease in question. The stronger the association, the greater the evidence
that factor “K” is involved. The greatestproblem with this type of study is that
it is very difficult to be certain only one variable is involved. Differences in
age, race, sex, soclo-economic status, residence, occupation, and others may be
very significant variables in the two populations one is attempting to compare.
Pesticides and Carcinogenesis
There are about 500 pesticides in common use. Many reports hàvè been published
to establish or refute a causal relationship of pesticides to cancer. Studies
have been along two lines, one; dosing rats with a particular pesticide to
determine if tumors result; second, studying human populations- -either determining
if individuals occupationally working with pesticides have a higher incidence of
cancer than those not so exposed, or in determining if a group of people already
with cancer have higher levels of pesticide in their tissues than a control group.
Various pesticides representing different classes of pesticides have produced
tumors in mice and can be rated as carcinogenic. These include p,p’ DDT, Aramite,
and Mirex. At this point in time it is not possible to show why certain chemical
structures are carcinogenic and others are not. Extrapolation of results from
mice to men is always a problem. As far as is known, cancer, due to pesticide
exposure in man has not been reported. -
Various studies have been done on groups of people occupationally exposed to
pesticides, but there is no evidence they were more at risk than the controls.
Likewise, several studies have been done on pesticide residue levels from tissues
of individuals with cancer, but most of these have failed to show any correlation
between pesticide residue levels and cancer.

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In a.pilot study in California, 32 the cytologic characteristics of sputum were
studied from 1362 individuals exposed to pesticides, and 419 controls. Five
cytologic characteristics were recorded: Inflammation - number of pus cells;
Irritation - increased number of macrophages and/or increased shedding of bronchial
mucosal cells; Allergy - increased number of eosinophils; Obstruction - increased
fibrin and Curschmann’s spirals; and Metaplasla - increased prevalence of cells
suggestive of squamous metaplasia of bronchial epithelium.
“In certain other chronic irritations histologic alteration takes place in the
mucous membrane of the bronchial tree. This is the squamous metaplasia. In squamous
metaplasia, portions of the normal pseudostratified columnar epithelium in the
bronchial mucosa are replaced by a stratified squamous epithelium. When this new
metaplastic epithelium has the same structure as the natural stratified squamous
epithelium, the exfoliated cells are indistinguishable from the normal squamous
epithelial cells.” 3
Exposed and controls were compared with these variables with the following results:
Comparison of Sputum Cytology Between a Pesticide Exposed
and a Non Exposed Pesticide Group
Controls (419) Exposed (1,362)
Percent ‘--s .-” .-’ . Percent Showin2
Characteristic
..
Inflammation
40%
36%
Irritation
29%
29%
Allergy
970
87.
Obstruction
127.
97.
Metaplasia
27%
4370
“Of these five characteristics studied, only metaplasia was greater among the
exposed than the controls. Detailed analysis of age and smoking habits failed to
account for these differences. Comparison with the prevalence of metaplasia
in other occupational groups indicate the prevalence of metaplasia in pesticide
workers is clearly excessive.” 2
What is the significance of finding a larger number of “metaplastic cells” in the
sputum of pesticide exposed individuals? There is no unanimity of opinion among
cytologist. “Some state firmly that metaplasia has no connection with the
development of lung cancer. Others believe that the transformation of bronchial
epithelium to a squamous cell type is an essential first step in the development
of squamous carcinoma of the bronchus since ‘metaplastic cells’ are almost always
found in large numbers in sputum smears which also contain malignant squamous cells.
It is important to emphasize that essentially all experienced cytologist agree that
the converse is not true; namely, the presence of ‘metaplastic cells’ by no means
implies impending malignancy. All agree, also, that metaplasia is a reversible
condition.” 12 The possible implication of these findings to human health demand
further investigation, and this is now in progress.
Summary
A number of products of our modern environment have been associated with cancer,
many others have been demonstrated as carcinogenic on animals. Their long-term
effect upon man is unknown. A number of pesticides have been demonstrated as

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64
carcinogenic and likewise their long-term effect is not known. The accumulative
effect of several carcinogens or synergistic effect of a carcinogen and other
chemicals working together is again not known. Due to a wide spread usage and
distribution of pesticides in our environment, it is obvious that continued long-
terni studies will be necessary to monitor the possible hazards of pesticide
carcinogens to man’s health.
LITERATURE CITED
1. Ackerman, L.V. and J.A. Regato, 1970. Cancer, Diagnosis
Treatment, and Prognosis. D.V. Masley Co. 783pp.
2. Shunkin, M.B. 1960. On the etiology of bronchogenic carcinoma.
In Spain, D.M. editor: The Diagnosis and Treatment of Tumors
of the Chest. N.Y., Grune and Stralton, Inc.
3. Cornfield, J., W. Haenezel, E.C. Hammond, A.M. Lilienfeld,
M.B. Shunkin, and E.L. Wynder, 1959. Smoking and lung cancer;
recent evidence and a discussion of some questions. J. rat
cancer dust, 22:173.
4. Clemmesen, J and A Nielson, 1955. The geographical and racial
distribution of cancer of the lung. Schweiz, Z. Aug. Path.
18:803-819.
5. Galy, P., R. Touraine, J. Brune, P. Gallois, R. Boudier, R. Loine,
P. Lhereur and T. Wiesendanger, 1963. Bronchopulmonary cancer
secondary to chronic arsenic poisoning in vinegrowers of
Beaujolais. Lyon Med. 210:735-744.
6. Stocks, P. and J.M. Campbell, 1955. Lung cancer death rates among
non-smokers and pipe and cigarette smokers; an evaluation in
relation to air pollution by bezpyrene and other substances.
Brit. Med. J. 2:923-929.
7. Mills, C.A., 1960. Motor exhaust gases and lung cancer in
Cincinnati. Amer. J. Med. Sd. 239:316-319.
8. Clayson, D.B., 1962.Chemical carcinogenesis. Little Brown and
Company.
9. Dunner, L. and M.S. Hicks, 1953. Bronchial carcinoma in. dusty
occupations; observations in boiler scalers and grain dockers.
Brjt. J. Tuberc. 47:145.
10. Buell, P., J.E. Dunn, and L. Breslow, 1967. Cancer of the lung and
Los Angeles type air pollution; prospective study, Cancer 20: 2139-2147.
or
10. Buell, P. and J.E. Dunn, 1967. Relative impact of smoking and
air pollution on lung cancer. Arch. Environ. Health (Chicago) 15:291-297.
11. Durham, W.F. and C.H. Williams. Unpublished, planned for 1972.
Mutagenic, Teratogenic, and Carcinogenic Properties of Pesticides.
Annual Rev, of Ent. 17:
12. Unpublished data, 1970. Community Pesticides Study, California
Project, Division of Pesticide Community Studies, Environmental
Protection Agency.
13. Liu, W., 1964. An Introduction to Respiratory Cytology.
Charles C. Thomas, Springfield, Illinois. 115 pp.

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65
MAN’S EXPOSURE TO PESTICIDES
Anne R. Yobs, M.D.
Pesticide chemicals are ubiquitous. Their presence has been reported in every
part of the environment——air, water, soils, crops, food, feeds, and many species
of wildlife-—and in some occupational settings. The exact pesticide ‘and its
concentration reported in the several parts of the environment vary with time
and geographic location of the study as well as with the sampling and analytical
techniques used by the investigator. Exposure to pesticide chemicals can and
does occur in the urban situation as well as on the farm, although concentrations
are generally lower in the city. In today’s cosmopolitan culture, certain of
these chemicals are used to prevent insect damage to clothing and such household
items as carpeting and rugs, to control fleas and other insects on pets, to pre-
vent disease spread through control of insect vectors both over land and in
airplanes, and to control insects as well as rodents in the home and garden.
Pestici es may also be found in cosmetics which contain lanolin, an oil of animal
origin.
Pesticides, like many other materials, may be transported great distances once
they have entered the air (and atmosphere) or water. Therefore, it can no longer
be assumed that one’s exposure will be limited to those chemicals which are used
locally.
In order for a chemical substance to affect a living organism, it must come in
contact with the organism or actually enter the body—-that is be absorbed into it.
Humans like other mammals may absorb pesticides through the gastrointestinal tract or
by ingestion; through the pulmonary tract or by respiration; and across or through
the intact skin; i.e., percutaneous,. For most of these chemicals, absorption Is
most efficient by ingestion. For others, however, absorption is just as efficient—-
and for some even more efficient-—when exposure is primarily through the respiratory
tree or the skin.
Many approaches have been used in the past in attempts to determine man’s exposure
to one or more pesticides. These have included the collection and analysis of
individual sampl meals or meals for an entire day as was done by Durham and co-
workers in 1965.’ In this study, arrangements were made with participants for
two plates to be served at the same time; one was used for chemical analysis while
the other was the •participant’s meal. The Food nd Drug Administration’s Market
Basket Survey takes a somewhat similar approach. 3 Here the diet of a hypothetical
18-year—old man is prepared for the table, then analyzed.
Documentation of respiratory exposure experienced by workers has been attempted
by analyzing filter pads from respirators or by measuring the pesticides in air
in the region of the worker’s nose and mouth using a portable micro-Impinger or

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66
other device and subsequently analyzing the collecting media or solvent. 4
Quantitation of percutaneous exposure has been attempted by analysis of cloth
patches attached to clothing during exposure and extrapolation of this informa-
tion to determine what total surface exposure would have been.
In all these, direct measurement of the pollutant itself is attempted under
actual exposure conditions. Obviously no one of these approaches measures the
total exposure to pesticides from all routes, nor are these approaches practical
for application to a number of individuals in an actual situation. Each, however,
is a valuable research tool.
Another approach is an indirect one whereby exposure is estimated by quantitating
known effects such as modification of enzyme activity. To use this approach,
quantifiable effects must be known to result from exposure to a pesticide chemi-
cal; ideally these effects should develop in definite increments as the level
of exposure increases. Also, the range of activity under normal or unexposed
conditions must be relatively narrow and fairly standard with little physiologic
variation.
Known pesticide effects on humans ar usually similar for an entire group of
pesticides, such as liver microsomal induction with chlorinated hydrocarbon
exposure, or permanent acetyl cholinesterase inhibition with organophosphates
but temporary reversible inhibition of the same enzyme after carbamate exposure,
the differences being ones of rate or intensity.
Efforts to identify and document other effects are directed toward study of indi-
viduals who have been acutely intoxicated or poisoned by pesticides and other
persons who have long—term occupational exposures to pesticides. Both these
groups experience pesticide exposure at a level which is many times that of the
general population. It is possible that some effects which develop under these
circumstances of heavy exposure may also occur at lesser intensity in the general
population. The majority of the long-term prospective or epidemiologic studies
of the occupationally exposed groups are performed in the Community Studies pro-
jects. 5 These studies are established by contract with State Health Departments
and/or local medical schools in areas of high or unique pesticide usage. Each
project has its own pesticide residue analytical laboratory and usually its own
facilities for biochemical testing. Subjects are drawn as volunteers from local
groups which are occupationally exposed to pesticides. These may be manufacturers,
formulators, professional applicators or farmers; a control group of the general
population is also followed by each study. Each volunteer, on entering the study,
undergoes a complete physical examination including EKG, hematology, and bio-
chemistry workup as well as appropriate’ tests for pesticide residue levels-—
usually in blood--and urinary metabolite excretion. A complete medical and work-
exposure history is also taken. These tests and histories are repeated or up-
dated at regular intervals. Data from all projects is then combined for evalua-
tion. From time to time, special efforts are also directed toward study of
cellular metaplasia, chromosomal aberration and neurophyslologic changes In these
groups. In a nutshell, every effort is made to follow every lead concerning
exposure—related health effects and to develop as many leads as possible. The
study group is primarily, if not entirely, male. Special studies concern problems
of other groups——such as jaundice in the newborn and maternal-fetal pesticide
residue levels. Once again, these techniques are valuable in research but are
not suitable for routine use in large groups.

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How, then, can one determine what is the average man’s exposure to pesticides
in a practical, fairly routine manner that will permit the development of a mass
of valid data over a broad geographic area? The most amenable approach is the
measurement of levels of the pesticides and their metabolites which are stored in
the body or which are excreted in the urine. Neither of these Is appropriate
for all pesticides nor even for all groups of pesticides.
The chlorinated hydrocarbon pesticides are relatively stable, are lipotropic and
tend to be stored in body fat. Therefore, metabolite levels in adipose reflect
the individual’s previous exposure to selected ones of the more widely used
members of this group——DDT, Dieldrin, the BHC isomers and heptachior. From
these measurements it is possible to estimate previous levels of exposure and
to compare exposure between groups. Levels in blood a e more affected by recent
exposures but levels occur in parts per billion or lO grams and consequently
fewer pesticides are identifiable.
The presence of DDT in humans was first reported by Laug in 19506. Since that
time there have been several reports of studies of pesticide levels in adipose
tissue In humans. Usually these have concerned small numbers of Individuals In
restricted geographic areas. 7 Comparison of results from one investigator with
those from other investigators must be done very cautiously because of major
changes in analytical technology and because of interlaboratory variation. At
such low levels and with instrumental variation, there is ample opportunity for
rather wide variation of results. Table 1 summarizes results from these studies.
In 1967, a nationwide program was initiated to measure chlorinated hydrocarbon
levels in human adipose of individuals over the country. This Human Monitoring
Survey has had a strong interlaboratory quality control program and sampling has
been perforned according to a statistical design (Table 2). Therefore, it is
possible to compare data with some confidence between years, geographic areas,
or on age, sex, or racial groupings. It will also be possible to compare data
on the basis of diagnoses when sufficient numbers of cases have been collected.
In the occupationally exposed groups, it has for some time been possible to
measure urinary excretion of DDA (water soluble metabolite of DDT) or PNP (para-
nitrophenol),metabolite of parathiop. These tests were not sensitive enough for
use with the general population where lower levels of exposure result in meta—
bolite excretion at levels below the sensitivity of the tests. Recent analytical
methodology development now makes it possible to estimate exposure to the organo-
phosphate pesticide group by measurement of common metabolites in the urine as
well as to other pesticides such as the carbamates, the phenoxy herbicides, etc.
through measurement of the parept compound or phenolic metabolites in the urine.
These procedures are now being tested in a pilot project to determine their
app1icabil ty to the general population before adding them to the national pro-
gram.
You may wonder that I have not included the determination of acetyl cholinesterase
activity as a monitoring device in humans. The range of normal for this test is
quite broad and is subject to considerable Individual variation, a fact which
makes this test unsuitable for general population monitoring.
Knowledge about man’s exposure to pesticides Is Important (1) In determining the
effects of altered pesticide usage patterns, (2) in determining trends and varia-
tions in exposure levels, (3) in fully understanding the impact of pesticides on
the ecology and (4) in predicting and studying the incidence of health effects
of such exposure(s).

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68
Preliminary evaluation of data from the nationwide survey of chlorinated hydro-
carbon levels in humans revealed an unexpected but significant geographic and
racial variation in levels of DDT which suggested the existence of another major
route of exposure for the general population other than food, most of which in
this country is shipped in interstate commerce and so is subject to control of
pesticide contamination through a system of legal tolerances. Ambient air was
suspected of being this route. There had been little study of pesticide con-
tamination of ambient air. Most work in this field had been problem oriented--
that is,-study of drift during application or local contamination after applica-
tion. An energetic program of ambient air sampling over the country has shown
considerable geographic and temporal variation of pesticide pollution of air.
Such pollution is a potential source of human exposure by respiratory, percu-
taneous or ingestion and as such would be reflected in the tests which have been
discussed.
REFERENCES
1. Chlorinated Hydrocarbon Pesticides in Cosmetics, by Walter F. Edmundson,
Vera Fiserova—Bergerova, John E. Davies, Dwight E. Frazier, and Gigi A.
Nachman; source: Industrial Medicine and Surgery , 36 (12) :806—809, Dec 1967.
2. DDT and DDE Content of Complete Prepared Meals, by William F. Durham, John F.
Armstrong and Griffith E. Quinby; source: Archives of Environmental Health ,
U(5):641—647, Nov 1965.
3. Residues in Food and Feed, by R. E. Duggan and F. J. McFarland; source:
Pesticides Monitoring Journal , Vol.1, 1—5, 1967.
4. Measurement of the Exposure of Workers to Pesticides, by William F. Durham
and Homer R. Wolfe; source: Bulletin of the World Health Orqanization ,
26(l):75-91, May 1962.
An Additional Note Regarding Measurement of the Exposure of Workers to
Pesticides, by William F. Durham and Homer R. Wolfe; source: Bulletin of
the World Health Organization , 29(2):279-281, Oct 1963.
5. Pesticides in Human Health: A Query, by L. C. LaMotte; source: Bulletin
of the Entomological Society of America , 15(4) 373—6, 1969
6. Occurrence of DDT in Human Fat and Milk, by E. P. Laug, etal.; source:
AMA Arch. md. Hyg. Occupational Med. , 3, 245 (1951).
7. Monitoring Food and People for Pesticide Content, by Wayland J. Hayes, Jr.;
source: Scientific Aspects of Pest Control (A Symposium Arranged and Con-
ducted by the National Research Council, Washington, D.C., Feb 1—3, 1966)
NAS—NRC Pub. No. 1402, pp. 314—342, 1966.

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69
TABLE 1
Concentration of DDT-derived Material in Body Fat of the General Population of the U.S.
DOE as Total DDE as
No. of Analysis DOT DOT as DOT DOT
Year Location Sas ,les Nothod ( ) ( ) ( ) ( S of totelJ Reference
1942 Louisville, Ky. 10 Colorlmetric a a a Hayes 1958
1950 Washington, D.c. 75 Colorlumtrlc 5.3 —- 5.3 - — Laug .A]... 1951
1955 Tallahassee, Fla. 49 Colorlmetric 7.4 12.5 19.9 63 Hayes ! .al., 1956
1954—56 Savannah, Ga. and 61 CalorimetrIc 4.9 6.8 11.7 58 Hayes 1958
Wenatchee, Wash.
1956 Atlanta, Ga. 36 CalorimetrIc 5.5 10.1 15.6 65 Hayes i .!i.. 1971
1961—62 Atlanta, Ga., Louis-
ville, Ky., Phoenix,
Aria., and Wenatthee,
Wish, 130 Colorimetrlc 4.0 8.7 12.7 69 Quinby etal., 1965
1961—62 Wenatchee, Wash. 2& GLCC 2.4 4.3 6.7 64 Dale & Qulnby, 1963
1962-63 Chicago, Ill. 282 GLC 2.9 8.2 11.1 74 Noffisan ].,1964
1964 Northeast, Midwest,
Deep South, and
Far West 64 GLC 2.5 5.1 7.6 67 Zavon etal., 1965
1964 New Orleans, La. 25 GLC 2.3 8.0 10.3 77 HayeS etal., 1965
1962—66 ChIcago, Ill. 994 GLC 2.6 7.8 10.4 75 Hoffman et ii .1967
1964—65 OhIo 18 .C 9.0 Schafer and
Campbell, 1966
1964—65 Florida 42 GLC 3.1 7.5 10.6 71 Radomsk l etal,1968
1964—65 Florida 12 GLC 3.79 7.7 11.5 70 Davies etal.,1965
1965—6? Florida ge Race
17 GLC 3.1 5.5 56 Davies et al.,1968
6+ W 90 GLC 6.1 8.4 73
0—5 NW 17 GLC 4.6 7.8 59
6+ NW 35 Q.C 12.0 16.7 72
‘ 1967 Florida 42 GLC 3.13 7.43 10.56 70 F lserova—Bergerova
!!AL. 1967
1966-67 Hawaii 30 d GLC 1.34 5.17 6.51 79 Casarett et al.,1968
29 e GLC 1.40 4.90 6.30 78
GLC 1.18 4.99 6.17 81
1966—67 LouisIana 62 .C 1.32 6.33 7.65 83 Selby ! . J_.’ 1968
TLC
1967 CalIfornia 64 GLC. 4.8 17.9 22.7 79 Rappolt, 1970
Rappolt and
Hale, 1968
1968 Florida .C Study not yet published in full Barquet 3..,l970
1967-68 Arizona 70 Q.C 1.54 5.10 6.64 77 Norgan and Roan,
1970
Not detected.
b These 28 samples were also tested for DOT and DDE content by a colorimetric method. These results are included In
the 130 samples listed above.
Gas—liquid chromatography.
e Perirenal fat.
mesenteri fat.
panniculus fat.

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70
Table 2
Mean Levels of Selected Chlorinated Hydrocarbon
Pesticide Residues in Adipose of the General Population (ppm)
National Summary Data by Year
Human Monitoring Survey
Preliminary Data
1967 _____ _____ _____ _____
1968 1968 1969 19701
722 3300 3237
11 21 23
1971
Mod.
Cal year
# samples
II states
Method
pp DDT
op DOT
pp DOD
op ODD
pp DDE
op DDE
Total DDT equiv
Heptachlor Epoxide
Die ldrin
- BHC
— BHC
— BHC
o — BHC
3264 2626
27 + DC
Mod.
MOG
1.15
0.14
0.03
0.00
4.12
0.04
5.97
0.08
0.15
non -
cleanup
1 • 28
0.06
0.13
0.00
4.22
0.04
6.22
0.05
0.14
0.00
0.28
0.00
0.01
non-
cleanup
1 .52
0.09
0.10
0.00
5.28
0.01
7.60
0.04
0. l 2
O .00
0.28
0.00
0.00
33 + DC
Mod.
MOG
1.20
0.13
0.04
0.00
4.02
0.04
5.81
0.08
0.13
0.00
0.28
0.00
0.00
Mod.
hOG
1 .53
0.15
0.04
0.00
4 • 08
0.04
6.26
0.06
0.13
O .00
0.28
O .00
O .00
0.00
0.29
0.00
0.00
1 Incomplete data 6/6/71

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71
PESTICIDE POISONING —A MEDICAL EXAMINER’S VIEW
BD Blackbourne
THE COMMUNITY STUDIED
The occupational and community hazards of a potentially lethal agent may be evalu-
ated by studying clinical and fatal cases of poisoning in a community that has
been at risk for a period of time. In Dade County, Florida (Metropolitan Miami),
a high utilization level of pesticides has existed over many years. Since the
origin of the Medical Examiner’s Office in 1956, a high percpntage of all fatal
poisonings have been documented.
In a subtropical area involved to this extent in agriculture, pesticides are very
necessary; but, at the same time, potentially dangerous. An estimated 250,000
pounds of organophosphate pesticides are used annually in Dade County.
During the past twelve years, over 100 persons in Dade County have died as the
result of pesticide poisoning (Table 1). Over half of these have been suicidal in-
gestions. Forty-one accidental fatal poisonings have occurred from organophosphate
and non-organophosphate pesticides (Table 2). The peak incidence of fatal acci-
dental poisoning occurred in 1963. Through an educational campaign directed to-
ward agricultural users and the community, the number of deaths has decreased in
subsequent years (Table 3).
FATAL ORGANOPHOSPHATE POISONINGS
In 1959, the first Dade County death from organophosphate pesticides (parathion)
was recognized. In the ensuing ten years, 56 deaths have resul’ted from these
agents. Of these, 28 were accidental poisonings, 26 suicides, and 2 murders,
Eighteen children died from organophosphate poisoning. Each death represented a
separate poisoning incident. In several cases, more than one child ingested the
poison. But in each case, only one died. Thirteen of the 18 children poisoned
were 2 years of age or younger; the youngest was 14 months old; 15 w&re Negro,
3 were white; 14 were boys, 4 were girls.
Eight of these 18 children found a bag or bottle of concentrated parathion and ate
it. Nine other children ingested small amounts of parathion spread about the
house, and especially the kitchen, for control of roaches or rodents. One child
died of Guthion poisoning.
The disposal of empty metal cans and drums containing any potent pesticides is a
very serious problem. Hot water or caustic washing .s not sufficient to rid the
container of the pesticide. Complete burning of the inner liner and all of the
pesticide residue is the only way that these containers may be reused. For
routine disposal, cans should be crushed or otherwise dam ged (so that they will
serve no secondary purpose) and then buried in the ground.

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72
Accidental occupational organophosphate poisoning resulted in three deaths during
this study. Two had sprayed with parathion the day prior to becoming ill. The
third man had dusted collard greens all day using a rag over his mouth instead of
.1 respirator.
Organophosphate poisoning associated with acute alcoholism resulted in the death
of five men. In each case, while highly intoxicated with ethyl alcohol (0.15-,
0.23-, 0.27-, and 0.44- percent ethanol), they picked up a bottle and, expecting
that it was more alcohol, drank it.
As with any potent drug or chemical when it becomes available in the community and
its lethal poison potential becomes known, those people inteiit on suicide will use
it. Forty-five percent of the organophosphate deaths have been suicidal poisonings.
i o persons with mischief on their minds turned to parathion. One woman put one
drop in the beer glass of a loan shark who was extracting $20 a week from her as
interest on a $100 loan. When he rapidly died, she pleaded that she had not in-
tended to kill him--only to make him sick. The other case concerned a man who
put parathion in his wife’s Kool Aid. Admitted to the hospital in such extreme
distress that she could not talk, she wrote “poison” and her common-law husband’s
name on a pad of paper held by a nurse.
NONFATAL ORGANOPHOSPHATE POISONINGS
An estimated 2,000 nonfatal.organophosphate poisonings occur yearly in the United
States. This figure may be compared with an estimated 200 fatal poisonir gs. The
majority of both fatal and nonfatal organophosphate poisonings occur in Texas and
Florida, where large amounts of these materials are used in agriculture. As in
all other forms of poisoning, in order to make a correct diagnosis, someone must•
suspect a toxic agent as the cause. After reviewing the patient’s symptoms, the
circumstances of his becoming ill, his age and occupation, and available knowledge
about tjie community, the most-likely responsible agents can be selected and labora-
tory tests performed. Only through rapid and close communication between those
having knowledge of thç patient and of the circumstances, the physicians treating
the patient, and the chemist performing the 1 tests can the correct poison be iden-
tified and therapy initiated.
Briefly, the signs and symptoms of organophosphate poisoning are: increased
sweating, increased salivation, muscle jerking, constricted pupils, wheezing,
severe abdominal cramps, muscle weakness prqgressing to paralysis, vomiting and
diarrhea, cyanosis and convulsions. Of equal importance in suspecting the diagnosis
of organophosphate poisoning is the rapid onset and progression of this un asual
symptom complex. If pesticide poisoning is not thought of, the illness may be re-
garded as a primary lung, brain, or heart disease.
NONFATAL PESTICIDE POISONINGS IN DADE COUNTY, 1964-1968
Ninety-two nonfatal poisonings were documented, 79 of them accidental exposures,
11 attempted suicides, and 2 possible attempted murders. Of the accidental poi-
sonings 1 26 resulted from occupational exposure and 41 involved children who had
ingested or otherwise had been exposed to the pesticide. Of the 79 accidental
poisonings, 40 involved parathion, 12 phosdrin, and 5 diazinon.
FATAL, ACCIDENTAL NONORGANOPHOSPHATE PESTICIDE POISONING
After excluding many suicidal poisonings by nonorganophosphate pesticides, 13 cases
of fatal accideutal poisoning remain in the Dade County files between 1956 and 1969.
The pesticides involved include: those used in building fumigation (4), arsenic
(2), tallium (2), phosphorus (3), and paraquat (1),

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73
The first documented fumigation death occurred in 1951--a 27-year old woman. In
January, 1963, a home fumigation using acrylonitrile (34 percent) and carbontetra-
chloride (66 percent) eventually lead to the death of a 41-year-old woman. In
December, 1965, a similar situation resulted in the death of a 22-month-old boy.
A fourth death related to tent fumigation. A 57-year-old woman alcoholic recently
discharged from jail was advised of the plans to fumigate, and said she would pick
up her sweater and leave. When the fumigation was completed the following day and
the house inspected, the body of the woman was found in the bathroom. Apparently,
she had re-entered the house sometime during the night for the purpose of suicide.
Two accidental arsenic deaths have involved small childreri. The mother of a two-
year-old child mixed up some arsenic and water one evening and absentmindedly
left it on the kitchen table. The youngster arose before her mother the next
morning and drank the liquid, thinking it was water. She lived 24 hours in the
hospital. The other child, 17 months old, apparently found a container of arsenic
because white powder was noted on his face when he became dizz ’ and began to cry.
He died 2 hours later.
The two recorded victims of thallium poisoning were 3 and 16 years of age, respec-
tively. Their uncle found a gallon jug of light yellow liquid in a ditch beside
the road. Thinking that it was motor oil, he took it home. The father of the
two victims tasted it and recognized it as honey. If the container had ever been
labelled, the label had come off, for there was no warning on the glass jug of
the powerful poison it contained. The 16-year-old died 16 days after ingesting
the honey, his 3-year-old sister died 4 weeks after eating the same honey. The
other members of the family survived.
The three phosphorus deaths include two children and an intoxicated man, who had
all ingested phosphorus. They each died from 3 to 9 hours after ingesting the
poison.
The single accidental paraquat poisoning involved an alcoholic woman who, while
intoxicated, drank a solution of paraquat thinking it was more liquor. Her hus-
band had brought the paraquat home for use in the yard.
WHAT CAN BE DONE
Action to reduce the fatalities and clinical poisonings from pesticides must in-
volve education of the agricultural handlers of pesticides, and also of the gen-
eral public.
Safety equipment--including gloves, face masks, and protective clothing--have been
prescribed for loaders, spraymen, flagmen, and others. This equipment must, how-
ever, be used to be effective.
Pesticide container disposal is a problem. Washing with hot water and soap will
not remove all of the pesticide residue; the potential for poisoning remains.
Large drums may be commercially reconditioned by burning the inner liner. Smaller
containers should be crushed or split with an axe so they will serve no secondary
purpose and then buried in the ground.
Pesticides are poisons and must be labelled. If removed from the original labelled
container, subsequent containers must indicate by prominent label description the
nature of the contents. All labels must be so affixed to the container that they
will not be rubbed off or washed off by rain. Potent and highly toxic agricultural
pesticides have no place in the home. Under ito circumstances should pesticides be
placed in food containers. No bait made by placing a pesticide on food is ac-
ceptable for home use.

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74
SUMMARY
J)uring a twelve-year period in Dade County, Florida, 41 deaths occurred from ac-
cidental pesticide poisoning. Twenty-five children were poisoned. Seven poison-
ings occurred durinj 5inmercial us T sticide and 7 involved persons whodrank
the pesticide while acutely intoxicated on ethyl alcohol.
Five principles are suggested to reduce fatal and clinical poisoning:
I. Observe precautions prescribed for the safe handling of pesticides in agri-
culture.
2. Make sure that pesticide containers are safely disposed of.
3. Do not take agricultural pesticide home for storage, or for use against house-
hold pests.
4. Do not place pesticides on food as bait or in food containers for storage or
transportation.
5. Always label pesticide containers so that the label cannot be washed off or
rubbed off.
Table 1. Pesticide Poisonings, Dade County, Florida, 1956-1968
Organo- Nonorgano- Sub
phosphate phosphate total Total
ACCIDENTAL 28 13 25 41
Children 18 7 7
Occupational 3 4 7
Alcohol 5 2 2
hsce1laneous 2
SuICIDE 26 46 72
HOMICIDE 2 2 4
TOTAL 56 61 117
Table 2. Pesticides Causing Accidental
Death
Pesticide
Number
of
deaths
Parathion
26
Guthion
1
V.C. 13
1
Methyl bromide
I
Acrylonitrile
3
Arsenic
2
Thallium
2
Phosphorus
3
Paraquat
1
Real Kill
1
TOTAL
41

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75
Table 3. Accidental Pesticide Poison-
ing, Yearly Incidence, 1957-
1968
Year Fatal Nonfatal
1957 1 NA
1958 7 NA
1959 5 NA
1960 2 NA
1961 2 NA
1962 1 NA
1963 9 NA
1964 4 22
1965 3 24
1966 2 11
1967 2 11
1968 3 11
TOTAL 41 79
NA--Information not available
Table 5. Nonfatal Accidental Pesticide
Poisoning’, 1964—1968
Pesticide
“4
Ce
u
o cdt c
•r4 O Ek
) 4 J .p-4 • O OU
s -I Cd
Ti .. k.-l O . 4
— 01 cd.. C /) Cd{ / )N ” 4C / )02C) 01
.,l U 4JQ•r4 uOcdcdOu I4 ,
.c u 4- ouo
Year o oE-< . 0
1964 13 5 4 22 9 14121 4
1965 1012 2 24 14 7 3
1966 5 4 2 11 7 3 1
1967 64 1 11 5 1 122
1968 7 1 3 11 5 1 1 4
TOTAL41 2612 79 0 .25122314
Table 4. Nonfatal Pesticide Poisoning,
1964-1968, Dade County,
Florida
Accidental poisoning 79
Children 41
Occupational 26
Miscellaneous 12
Attempted suicide 11
Attempted murder 2
TOTAL 92
Table 6. Fatal Accidental Pesticide
Poisoning, 1964-1968
Poisonin
:
Pesticide
Year
0)
.4

“4
ri
.
U
“ 4
Cd

0
•rl
4J
cd
QI

U
u
0
.4
0)
.
J
0
•
— n
CdtO

.rl
0)
i O
Cd• U)
4 . U I
DUO
E—< .
0
•rl
,
‘ J
Cd
s-i
Cd
n .
0
•
.



0)
“4
•‘l
•s-i
4
4

0
“4
) .
s-i
U
•
O
Cd
I
Ce
.•
1964
1965
1966
1967
1968
TOTAL
3
3
1
1
8
0
1
1
2
2
6
.4
‘3
2
2
3
14
3
2
2
2
2
11
1
1
1
1
1
1

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77
POISON CONTROL CENTERS AND THEIR FUNCTIONS
Henry L. Verhuist
Following World War II, there was a proliferation of new chemicals and new
common household products. The names, characteristics, and toxicity of
these new chemicals were unfamiliar to practicing physicians. Even the
medicines which were their tools had unknown facets when they were ingested
in an acute overdose. Manufacturers who might expound on their drugs’ thera-
peutic effects, or reveal their collection of reported adverse reactions,
frequently had few data on acute overdosage. These were new problems to the
physicians. However, many of the old problems never had been resolved com-
pletely, and if they had, this information had not received wide circulation.
Among the latter were such questions as: were matches really poisonous;
did shoe dyes actually contain aniline and, if so, which ones; and why
tobacco with its high nicotine content was not causing fatalities among
children who were ingesting it.
According to a 1950 survey, over 50 percent of children’s accidents reported
to pediatricians were due to potential poison ingestions. At the same time,
the pediatrician was understandably unfamiliar with such chemicals as
sodium tripolyphosphate, ammonium thioglycollate, dimethyldistearyl ammonium
chloride, and many other chemical ingredients found in household products.
However, knowledge of these chemicals was necessary for the proper treatment
of an ingestion.
Because of this knowledge gap and because there were hundreds of thousands
of such ingestions annually, the Illinois Chapter of the American Academy of
Pediatrics initiated a pilot project in Chicago known as the “POISON CONTROL
CENTER.” From its inception the project received the cooperation of the
pediatric services in the local major hospitals, the State Health Department,
and the State Toxicological Laboratory. With these organizations serving as
a catalyst, a working unit was formed representing the local medical society,
some 20 hospitals, four full-time health departments, five medical colleaes,
the Illinois Chapter of the Academy of Pediatrics, and the American Public
Health Association.
The Chicago Poison Control Center opened in November 1953. It provided
information on and treatment for poisonings, and had the further objective
of establishing a program of prevention. The number of other poison control
groups which subsequently were ordanized with the same goals as those of the
Chicago Center can be considered a tribute to the latter’s success. The new
centers soon found, however, that they were duplicating one another’s work
in compiling information and that some information gathered by one center was
not always being distributed to the others. Moreover, clinical and epidemio-
logical information about poisoning experiences were not being collected. It
became apparent that some coordination of poison control center activities was
necessary.
By 1956, sixteen (16) centers had been established in major metropolitan
areas. Most were established by the pediatric service of the children’s
centers in the area. New York City’s, the only exception, was placed in the
Health Depav’tment. The operation of all the centers was fairly uniform. The
chief of the pediatric service served as the director. Residents staffed the
program and answered requests for information. The hospital assisted in pur-
chasing necessary texts, journals, and special reference material. Descriptions
of the first centers made it clear that the program was utilized mainly by
physicians treating emergency ingestions.

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78
The poison control movement gained much publicity and resultant popularity throughout
the nation. Because of this, many civic organizations as well as medical and
paramedical organizations encouraged establishment of poison control centers in
local hospitals. Unfortunately, in some instances, the local hospital had
insufficient personnel to perform the functions. The community might have had
better service had they concentrated on improving the emergency treatment facilities
and utilized a center in one of the larger medical centers for information services.
We have continued to stress the need to differentiate between Poison Control Centers
and Treatment Centers. The designation of poison control centers is made by State
Health Departments since medical practice is licensed by the State. However, the
individual States have interpreted the guidelines for centers differently. Thus,
we have one center in Oregon located at the medical school compared to approximately
100 in the State of Illinois, but, most States have less than twenty (20) centers.
The expertise of the staffs of the poison control centers appears to us, and other
knowledqeable observers, to increase with the number of calls received. It seems,
therefore, that the limited number of centers, designated by most states, would
have advantages. We now have a total of 560 designated centers.
The impact of the program to a hospital serving as a center is illustrated by an
article on the Boston Center.* It states the number of calls increased from an
average of 20 per month in 1954 to nearly 500 per month in 1960. Seventy (70)
percent of the calls were from the public. The report also gives information on
seriousness of ingestion of 800 cases. Thirty-six (36) percent required no treatment,
twenty-nine (29) percent received home treatment, thirty-one (31) percent were
treated at the hospital and four (4) percent did not give the information.
The function of the poison control center, then, is to have available information
on the formulation 0 f household products or chemicals so information on the toxicity,
symptomatoloqy and treatment may be furnished when an emergency occurs. This is
not nearly as simple as it miqht sound. With the exception of medications and a
few chemicals which have been ingested frequently, there is limited data except that
obtained from animal studies. In many cases no animal data is available on
combinations of chemicals, but only the individual components. In such cases
only individual data can be given and it is necessary that the physician, or the
center, determine the possible extent of the danger. There are some who believe
such estimations are subject to many errors. This may be true, but, some action
must be taken. Here, the busy center has the advantage since the chance of a
previous experience is greater and it dan call on past knowledqe.
Some of you who have utilized a center are probably concerned by the general
nature of the treatment given. There is a mistaken impression that a specific
antidote exists.for every poisoning. This is not true. In reality, only six or
seven specific antidotes are available. Several of these are effective for more
than one chemical, but, still the number of substances so treated is small. The
rest of the information involves symptomatic treatment and contraindications
which may be life saving.
I believe it is necessary that we discuss several areas in which poison control
centers are of very limited value. First, they are not laboratories to oerform
chemical analysis on unknown products or gastric contents. The public has an
impression that modern science has progressed to a point that the identification
of an unknown substance is but a few minutes work. Most of you know this is not
correct. It can require many hours or days of experts’ time with the most
expensive equipment to identify some unknowns. - Second, center personnel cannot
make a diagnosis that a patient’s clinical condition is necessarily associated
to a chemical exposure. They can only give the signs and symptoms of a chemical
intoxication. The treating physician must decide if the illness is related to
the exposure.
*Robb, Elwood and Hagqerty, Evaluatlon of a Poison Control Center-American Journal
of Public Health 53:1751 (November 1963)

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79
Now I should like to discuss the historical evolution of the National
Clearinghouse. --
On November 12, 1956, at a meeting of The American Public Health
Association, a recommendation was made that a National Clearinghouse for
Poison Control Centers be set up by the U. S. Department of Health, Education,
and Welfare. This meetin was attended by representatives from poison control
centers and from such national organizations and government agencies as the
American Academy of Pediatrics, The American Pharmaceutical Association, the
Food and Drug Administration, the National Research Council, the Children’s
Bureau of the Public Health Service. In compliance with the recommendation,
the National Clearinghouse for Poison Control Centers was designated as an
activity of the Public Health Service in the Accident Prevention Program.
It is now located in the Food and Drug Administration, Office of Product
Safety.
The National Clearinghouse contacts industry for the information that
manufacturers and distributors can contribute on their products. In this
way, it is possible to keep track of new products which may be poisonous
and of changes in the composition of existing products. Government agencies
are also a source of a large amount of significant data.
There is increasing willingnessby industry to supply information about
their products, although the material submitted varies greatly. In some
cases we are supplied only formulations. Some furnish expected symptoms
and/or treatment recommendations. Fewer supply information on toxicity.
However, there has been a noticeable increase in information supplied
since the passage of the Federal Substances Labeling Act of 1960. Most
manufacturers now determine if the LDç 0 is less or greater than 5 gm/kg.,
which is the limit set by that Act. Once information on •the formulation
is obtained, a statement of toxicity and treatment is developed by the
Clearinghouse, if one is not included by the Company.
An indexed card file for use of all poison control centers has been
distributed. The cards in this file are indexed by trade name and contain
such information as composition, concentration, and lethal dose of each specific
agent; plus symptoms and treatment of poisoning by the acient. Supplements
are sent to the centers as new products come on the market, and as existing
products come to the attention of the Clearinghouse. A more extensive card
file system is kept at the National Clearinghouse.
A bulletin is published periodically containing trends and statistics
obtained from the poison report form analysis. New work done on poisonous
or potentially poisonous materials, reports of new treatments for poisonings
found in the literature or used by individual poison control centers,
interesting cases of poisoning and abstracts from the literature on poisoning
are contained in the periodic bulletins.
The Division of Poison Control has developed a reporting system throuqh
poison control centers to maintain surveillance of products being ingested,
inhaled or absorbed to determine any hazards produced, extent of damage
and treatment rendered. The system could better be called a monitortng
orogram since we receive reports only when information is sought from a
center by a parent or physician following an exposure. Many cases are
treated by hospitals and physicians who already have sufficient toxicity
information. Also, we get only limited fatality reports since death may
occur days after the ingestion and a follow—up report is not always made.
Nevertheless, with 115,000 reports received in 1970 we believe we have a
representative cross section of products which are taken by children and

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80
those which are causing injury. Semi-annual tabulations are run for
internal use by the Food and Drug Administration. Copies are available
to the Department of Aqriculture. Individual experience with products is
supplied to the manufacturer of the product on request. This system does
not- provide data about environmental contamination or the possible long-term
hazard of a chemical. Within the last three or four years there has been,
however, a great increase in reports of intentional ingestions. The number of
calls requesting treatment information for intentional ingestions has risen
steadily to a point where one center reported 50 percent involvement.
Discussion :
Data collected for many years demonstrate that children under 5 years are still
the primary group involved in accidental poisoning. The 1970 poison control
centers reported 76,155 ingestions to us for this age group. Medicines
renresented about 50 percent of the ingestions. Of interest to us is the 30
nercent reduction in aspirin ingestion in the past two years. Much time and
effort have been spent in programs to educate parents that this product should
be stored out of reach of children. This reduction is an indication that such
efforts can be fruitful over extended periods of time.
Cleaning and polishing agents represent 14.4 percent of the reported ingestions.
The most serious categories in this group are the caustics and petroleum
distillated contained in furniture polish. The hospitalization rat s are
approximately 20 per cent and 11 percent respectively. Pesticides account for
5.2 percent. Insecticides and rodenticides are most frequently involved.
Hospitalization is reported at 6 percent level. For reference, 5 percent of all
children are reported to be hospitalized although some for overnight observation.
A table reporting data by category of products is included for your review.
The program has given us information on some real problem areas and removed
pressure on others. With a few exceptions, cosmetics have not created a problem.
Caustics are still a threat to the health of any child obtaining them, as are
some products containing petroleum distillates, particularly mineral seal oil.
Carbon Tetrachioride is now banned as a household product. However, there is
an allowance for small amounts left as residual during manufacturing processes.
Data collected through the reporting system has supported several actions to
ban other products which are dangerous for consumer use.
Recent legislation can require changes in formulation of some common household
products. It will be necessary that careful evaluation of all substitute
chemicals be made to determine their safety as well as the overall product
safety. However, there must continue to be a constant surveillance of data
from human experience, for animal studies are not always indicative of human
reaction to a chemical. We believe the data collection system through poison
control centers will enable us to maintain this surveillance.
For several years we have been developing and testing a system for computer
retrieval and delivery of the information to centers. This will eliminate lost
cards and expedite adding information. Centers in Boston, New Orleans, Detroit,
and Kansas City are using a program with approximately 5,000 items on the data
bank as a pilot program. Accumulation of data concerning injuries is necessary
for proper evaluation of hazard and treatment recommendations. This has been
expedited through use of automated data processing equipmBnt. Statistical data
from poison reports have been so tabulated by trade name for the past two years.
The data in the bank will also include a statement of results of previous
ingestions as reported through the centers. Thus, the physician will be aware
of injuries caused by a product during the previous year. Information is
delivered by telephone lines and displayed on Cathode ray tubes. We are very
pleased with the results.

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81
PESTICIDES IN AN OCCUPATIONAL SETTING
Louis Kaplan
The New Jersey Pesticide Project has a unique opportunity to study
workers in the pesticide industry, since the State has the largest
concentration of pesticide plants in the country. Because we do have
so many plants, much of the information and data for this report comes
from our experience and work in New Jersey. It should be noted that
there is really very little difference between a plant in New Jersey
and one in Colorado, Florida, or any other state. The observations and
conclusions herein incLuded generally apply equally, I would think, to
the workers in most pesticide plants.
Our state has approximately lkO pesticide formulating, manufacturing,
and distributing plants, employing about 5000 plus pesticide-exposed
workers. Most of the material in this presentation is derived from
continuing studies of 132 pesticide workers in nine plants and a
concentrated study of a herbicide plant of 73 employees. Thus, a
total of 205 pesticide workers is involved.
Long-term participants in the program have been given regular physical
examinations, electrocardiograms, chest x-rays, and a complete spectrum
of biochemical examinations. Results are compared with a control group
of 52 minimally exposed subjects. In addition, our field men are
routinely in contact with the participants to keep their occupational
and medical histories current.
Some general characteristics of most pesticide plants are; few
employees (usually 20 or less), makeshift equipment and plant, minimal
supervision, poorly designed exhaust ventilation, and insufficient and
rarely used personal protective equipment and sanitation facilities.
Some, not all, plants of large national concerns present a different
picture. Usually, they employ more than 20 workers, are well supervised,
supply uniforms and good personal protective equipment, occupy well
designed quarters, and have adequate equipment for manufacturing,
processing, ventilation, and prevention of environmental contamination
problems.
pesticide Plants in the Program
Perhaps a profile of a typical pesticide formulating plant would be
helpful at this time.
Plant A - Profile of a Typical Pesticide Formulating Plant
Formulating Plant “A,” located near Trenton, is engaged in the custom
formulation o pesticide chemicals. Customers include many other
New Jersey pesticide companies, Centra]. Jersey farmers, custom pesticide
applicators and pest control operators. This plant formulates a

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82
variety of pesticide chemicals, the bulk of which consists of organic
phosphates and chlorinated hydrocarbons. A partial list of finished
products includes: Parathion, Guthion, Malathion, Abate, Baytex, DDT,
Aidrin, Chiordane, Lindane, DieLdrin, and Sevin. This plant employs a
total of 22; 19 male workers being directly engaged in pesticide
handling activities. Employment is quite stable, with low turnover.
Specific operations include: milling and mixing of wettable powders
and dusts, granule impregnation, liquid mixing, packaging, warehousing,
and shipping. Operations are to a large extent manual. There are small
batch operations, and larger production runs of single pesticides, such
as Malathion.
The following protective equipment is supplied but its use is more or
less left to the discretion of the individual (this means almost never
used): approved respirators, nuisance dust respirators, rubber gloves,
rubber aprons, face shields, and some hats. Fairly effective local
exhaust ventilation is provided at the dust mill (feed site and
discharge site of mixed pesticide dust) and the granular mill (bagging
site). Design of hoods of these exhaust systems is poor and airborne
contaminants can be observed in the plant environment. No local exhaust
ventilation is provided for the liquid mixing operation, which is in the
same building with the above-mentioned milling operations, located near
a pyrethrin-blending operation in an adjacent building. Most workers
spend the majority of their time within the main building, and are
exposed to pesticides, both at their particular duty station and con-
tamination from adjacent operations. Plant housekeeping is a continuing
problem, as the building is not particularly designed to facilitate
clean-up. The bulk contamination of floors is usually removed by manual
sweeping methods on a daily basis, hopefully; usually toward the end of
a work shift, which results in further contamination and exposure hazard.
From time to time, when working with chlorinated hydrocarbons, the
mixing operator has been observed preparing laboratory control samples
with his bare hands. Workers in this plant, besides never showering at
work, generally, do not remove their work clothes or work shoes when
leaving the plant. They go home as they are, and of course take all the
goodies with them, to be distributed to the whole family. The best you
can say about their protective and hygienic precautions is that they
occasionally wash their hands. A number of acute pesticide intoxications
have occurred here, and subacute incidents are commonplace.
A few brief comments on some of the, other plants are in order. One
large plant provides dust milling by air-impaction methods, blending
and packaging services. Although it formulates a number of compounds,
the main pesticide formulated there is Carbaryl. This plant produced
considerable amounts of DDT up until 1963, and serum residues of DDT
and DDE are consistently high in those senior employees who formerly
worked on DDT.
An interesting case came to light in this plant. One worker showed
zero DDT and DDE residues in his blood. After an investigation and
many evasions, this man finally admitted that he was on an anti-
convulsant regimen for epilepsy.
Another plant is a general formulating plant, with intensive operations
in liquid, granular, and dust formulating of organophosphates. Much
parathion work is done here. Although this is what we would call a
“clean” plant, the employees are suffi ièitly exposed to the more toxic
organophosphates to cause frequent cholinesterase depressions and
complaints of dizziness, nausea, weakness, etc.

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83
Other plants monitored are general formulating plants, where the
workers are exposed to a variety of pesticides, and where plant health
and safety conditions are uniformly poor.
Environmental Samp1ing in Plant A
Table 1 shows a comparison of environmental air samples taken in a
plant which does a considerable amount of organochiorine formulating;
as opposed to results obta±ned in random outdoor sampling. Note the
comparatively large amounts of DDT, DDE, and DDD in the air of the
pesticide plant. Also, please note that the plant residues are in mgm
per cubic meter, and the outside residues are in nanograms per cubic
meter. Converting, we get 570,000 to 7,200,000 ng/M 3 of DDT in the
plant, compared to 0.6-3.2 ng/M 3 in the outside ambient air.
TABLE 1
Comparison of Environmental Air Sampling*
(Range)
p,p ”-DDT p,p’-DDE p,p’-DDD
Plant A (mg/M 3 ) 0.57-7.2 0.018-0.20 0.027-0.43
Ambient Air (ng/M 3 ) 0.6-3.2 0-1.0 0-T
*In_plant sampling vs. random outdoor sampling.
Pesticide Industry Fires
We have experienced three pesticide industry fires over the past few
years, and we would like to briefly discuss one which was considered
a major conflagration. In August 1971, a multi-building chemical
warehouse in Kearny, New Jersey was destroyed by fire. Products
included: Vapona, Gardona, Phosdrin, Ciodrin, Aidrin, Dieldrin,
Endrin, and many others. There was at least a 12-hour lag before the
parent company and the State authorities were, notified. Suffice it to
say, that proper procedures in fighting this fire were, generally, not
observed. Disposal of the pesticide resides and debris was the subject
of numerous conferences and meetings. Finally, a plan emerged to place
the debris in segregated, above-ground concrete basins, separating the
organochlorin,es from the organophosphates, and treating with lime to
maintain an alkaline pH. The organophosphates were to be treated until
decomposed; and, the organochiorines were to be monitored regularly,
and finally disposed of by methods stipulated by the State, such as
incineration at high temperatures (900-1,000° C) in an adequate
facility, equipped with an efficient collection system for removal of
toxic dusts and gases. A recent check-up on the disposal sites revealed
a great many inadequacies in carrying out the disposal plans. The
concrete basins were not completed, pesticides were haphazardly dumped
on the ground, etc. It is quite apparent that proper guid lines must
be established in handling pesticide fires, and proper control, inspec-
tion and follow-up procedures worked out by the State Department of
Environmental Protection. From our experiences, industry’s Pesticide
Safety Team Network did not work, and it is strongly suggested that the
proper State authorities, with the cooperation of the Federal Environ-
mental Protection Agency handle such emergencies rather than rely on
the Pesticide Safety Team Network to do so.

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84
Reports on Studies Made in New Jersey
Appreciable differences in blood cholinesterase serum pesticide
residues, urinary metabolites, and biological testing continue to be
observed in our pesticide-exposed group, as compared to the controls.
Periodic highly elevated DDT and DDE blood residues are being found in
ex-DDT formulators. The highest value of 700 parts per billion was
found in a service worker, who has not formulated since 1958. Incident-
ally, this worker recently died of a heart attack. Imagine what our
esteemed biostatisticians could do with this piece of information--such
as predicting heart attacks based on sera DDT residues, using the
Weibull mortality function.
We continue to see a number of sub-clinical and clinical pesticide
poisoning cases among our subjects, especially when exposed to the
more toxic organophosphates, such as parathion and phosdrin. In these
plants, where toxic organophosphates are formulated, abnormal cholin-
esterase values were and are commonplace. Twenty-eight out of 110
cases of pesticide poisonings investigated by the Project are pesticide
workers.
Table 2 demonstrates percent abnormals in cholinesterase and pesticide
residues.
TABLE 2
Abnormal Cholinesterase and Pesticide Residues
in IndustrialWorkers
Cholinesterase (I.U.) Serum Residues (ppb)
No. RBC Plasma DIY DDE Dieldrin
(< 8) (<3) (>20) ( 30) ( - 5)
Industry 132 15% 24% 45% 61% 38%
Controls 64 8% 11% 0% 14% 0%
Table 3 compares serum pesticide residues of formulators, general
population, and controls.
TABLE 3
Co parison - Serum Pesticide Residues
(p pb)
General
Controls Population Formulators
Residue Mean Range Mean Range Mean Range
p,p t -DDT 4.4 0-23 5.6 1-12 28.9 0-304
p,p’...DDE 14.3 0-27 20.8 7-67 28.0 2-187
Dieldrin 1.1 0- 6 1.3 0- 5 7.5 0- 64
Sample Size 54 57 65
Table 4 reports the percentage of tests which were.outside the normal
ranges for the blood biochemistries. Some biochemical responses
showing differences from the controls were: glucose, uric acid,
cholesterol, calcium, lactic dehydrogenase, alkaline phosphatase,
transaminases (SGOT and SGPT), creatine phosphokinase, creatinine,
albumin.

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TABLE 14 85
Biochemistry (SMA-12 )
(Values cited are percentages of total tests
showing abnormal results)
Controls Industry
(N = 112) (N = 150)
Glucose 9.8 16.7
Uric Acid 3.6 7.3
Cholesterol 17.0 214.3
Calcium 3.6 9.14
LDH 16.1 24.7
Alkaline Phosphatase 8.1 17.7
SGOT 13.4 16.0
SGP 14.5 8.0
CPK 6.2 9.3
Creatinine 0.9 5•14
ALbumin 8.9 14.7
In a morbidity study , a review was made of all the positive and ab-
normal physical findings of our control group versus our pesticide
industry group. These data were obtained by medical examinations
and medical histories.
In Table 5, significant differences are noted in chronic cough and
sinusitis, dizziness and headache, hearing difficulties, and hyper-
tension. Positive nervous system findings occur in 50 percent of the
pesticide industry workers as compared to 35 percent of the controls.
Gastrointestinal complaints were 7.5 percent in controls and 12 percent
in industry. Back problems are twice as prevalent in the industry
group.
TABLE 5
Number of Positive Physical Findings
Pesticide Industry vs. Controls
Pesticide
Category Controls (40) Industry (112 )
Back Trouble 5 24
Chronic Cough and Sinusitis 6 31
Dizziness and Headache 3 18
Hearing 3 214
HypertensiOn 1 23
Nervous System 14 55
Gastrointestinal 3 13
Special Study in New _ Jersey Plant Producing Malathion
Cooperative arrangements were made with a large plant for Dr. Arthur E.
DePalma, at the time, Principal Investigator of the New Jersey Project,
to examine past personnel and medical records of a group of employees
who worked directly with organic phosphates, Malathion in particular,
for a lon period of time. This company has a medical department,
where medical examinations and other pertinent testing are conducted
on a regular basis. This plant is what we would term a “clean plant,”
in that housekeeping is exce1l nt and protective equipment and protec-
tive measures are good. The workers examined were long-time employees;
some going back 15 years or more. Production of Malathion started in
1951.

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86
In an examination of the medical histories of 34 men, the following
information was obtained;
Skin (20 incidents), and particularly eye irritations (237 incidents),
were frequent but they seemed to lack chronic sequelae. Monthly
cholinesterase testing was generally normal, and occasionally, when
abnormal, the particular individual was transferred out of organo-
phosphate work. One case of systemic poisoning was found. Eighteen
respiratory tract irritations were noted. Eight of the men revealed
hypertension in more than one examination.
In summary, in this plant there were definite indications of a high
incidence of skin and eye irritations, some respiratory tract irrita-
tions, some cases of hypertension; and one case of organophosphate
poisoning. Aside from this, there were no other indications that these
34 men were suffereing from any chronic adverse health effects.
Dr. Reich’s Study of 1969 Data
Dr. George A. Reich, in analyzing data printouts of 1969 subset
information generated by Mrs. Janet R. Daling from the State of
Washington, found that in a group of 741 workers, 311 hada total of
411 reactions to pesticides.L The greatest number of reactions resulted
from exposure to the organophosphates. Ninety-three reactions were
reported as a result of exposure to parathion. Symptoms reported, some
of which are shown in Table 6, were: headache, nausea, dizziness,
dermatitis, tearing, rhinitis, blurred vision, vomiting, fatigue,
muscular weakness, difficult breathing, abdominal pain, and a few others.
TABLE 6
Major Symptoms Reported Due to Pesticides Among Workers
Symptoms Occurring
10% or More of Cases
Chemical Class
Reactions*
In
Headache
Chlorinated Hydrocarbon
Nausea
Insecticides
68
Dizziness
Dermatitis
Dermatitis
Chlorinated Hydrocarbon
Rhinitis
Herbicides, etc.
32
Tearing
Headache
Headache
Organophosphates’
243
Nausea
Blurred Vision
Dizziness
*01 chemical classes with at least 10 cases are included.
Some Published Reports on Other Studies of Pesticide Workers
A study was made by Dr. AA P. Poland, et al of 73 employees in a
2,4,-D and 2,4,5-T p1ant. These compounds are organoch].orine herbi-
cides: dichioro- and trichloro-plienoxyacetjc acids.

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87
Chloracne was found (moderate to severe lesions) in 18 percent of the
workers. Sixty-six percent more had some degree of acne. No clinical
porphyria could be currently found, and one worker had persistent uro-.
porphyrinuria. No systemic toxicity differing from normal populations
was found. We have received information from a law firm that most of
the forner employees of this plant, which is now out of business, have
filed Workmen’s Compensation suits against the company.
A report was made by I. Hoogendarn, et al, on a health survey of 300
workers in plants manufacturing aidrin, dieldrin, and endrin (toxic
organochiorine pesticides) over a period of up to nine years. Although
no fatalities and apparently no permanent damage occurred, 17 of the
workers had convulsive intoxications, and five of the 17 had more than
one convulsion.
Nine cases of convulsions in pesticide workers handling Thiodan, a
highly toxic chlorinated hydrocarbon insecticide, are reported in a
paper by Dr. Thomas S. Ely, at al. 4
Dr. I. R. Tabershaw, et al, made a follow-up study of 235 individuals
three years after acute organophosphate poisoning. 5 Of this group, 114
had clearly defined organophosphate poisoning. Forty-three of the llLi.
had complaints for more than six months after poisoning, and 33 still
had complaints three years after intoxication. These complaints were
in th e following categories: optic, headaches, chest pains, shortness
of breath, cardiovascular, neuropsychiatric, and miscellaneous.
Environmental, clinical, and biochemical evaluations were made by
Dr. M. Wasserman, at al, over a five-year period, on pesticide workers
in a pesticide manufacturing plant in Israel. 6 The report is based on
data obtained by using the Cornell Medical Index Questionnaire. One
hundred and forty workers in the pesticide manufacturing plant were
compared to 71 workers from a textile plant as the control group. The
results indicated:
1. There was a high incidence of complaints in the
pesticide workers group.
2. Both groups demonstrated similar frequency of
complaints in those sections relating to mood
and feeling patterns.
3. Higher incidence of positive answers in the
pesticide group, as far as the respiratory,
cardiovascular and nervous systems are concerned.
4. In both groups, the number of complaints increased
with age.
Table 7 lists positive answers to various sections of the CMI.

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88
TABLE 7
Positive Answers in CMI According to CMI Sections
Positive Answers (Mean)
Sections PMP* Control Probability
Eyes and Ears 1.05 0.86 p 0.10
Respiratory System 1.81 1.07 p < 0.03
Car?diovascular System 1.28 0.7k p . 0.01
Digestive System 3.27 2.k8 p 0.05
Musculoskeletal. System 0.9k 0.67 p 0.10
Nervous System 1.77 1.15 p < 0.03
Genito-Urinary System 0.92 0.76 p > 0.10
Fatigabi].ity 1.13 0.87 p 0.10
Frequency of Illness 0.72 0.39 p 0.10
Miscellaneous Diseases 1.11 0.77 p < 0.10
*p 4p - Pesticide Manufacturing Plant.
Dr. T. 1-1. Milby, et al, reported on blood examinations of kO people
working in a lindane plant, compared to kO unexposed controls. 7 The
following significant differences were found: creatinine, reticulo-
cyte count, white blood cell count, polymorphonuclear leukocyte count,
and blood lindane count. Although the differences were significant,
only one fell outside the normal range--the blood lindane.
In a report by G. G. Mikailova, poor sanitary and hygienic working
conditions and personal protection in working with many pesticides
(organochlorine and organophosphates) has led to functional disorders
of the nervous system, coupled with the appearance of anemia and
disorders in the enzyme systems. 8 Abnormalities were also reported in
the protein-forming functions of the liver.
CONCLUSIONS .
In summation, there is data on hand now to state that pesticide-exposed
workers in pesticide plants differS from minimally-exposed controls in
a number of parameters:
1. Abnormal cholinesterase (low) and abnormaLly high
organochlorine residues in sera.
2. Blood BiochemistEy - Higher rate of abnormals in
glucose, uric acid , cholesterol, calcium, LDH,
alkaline phosphatase, SGOT, SGPT, CPK, creatinine,
and albumin.
3. Probable renal and hepatic dysfunctions , caused by
excessive exposure to pesticides.
4. Morbidity , in the following categories: back trouble,
chronic cough and sinusitis, dizziness and headache,
hearing, hypertension, nervous system, gastrointestinal,
cerebrovascular, cardiovascular, nephritis and nephrosis,.
dermatitis.

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89
Occupational health hazards as a result of heavy exposure to pesticides
are the rule and not the exception in most pesticide plants. Where
protective measures and plant and personal hygiene are good, and this
is the exception, exposure to the less toxic pesticides can be held to
a minimum. However, it should be pointed out that no matter how good
plant protective measures are, exposure to the more highly toxic
pesticides, such as parathion, phosdrin, etc., is hazardous to the
health of the pesticide worker.
5. Acute pesticide intoxicat ions and sequelae - The
number of acute cases of pesticide poisoning and the
frequency of subacute cases far exceeds those reported, in
the general population.
Further research and investigations are necessary to confirm what has
been found to date, and to relate the subtle effects of repeated
pesticide insults on man’s health to chronic disease states.
REFERENCES
1. Reich, g. a.: Unpublished tables from 1969 subset data,
Pesticide Community Studies.
2. Poland, A. P., Smith, D., Metter, G., Possick, P.: A Health
Survey of Workers in a 2,k, D and 2,k,5-T Plant. Arch. Environ.
Health 22:316-327, (March) 1971.
3. Hoogendam, I., Versteeg, P. J., de Vliegor, M.: Nine Years
Toxicity Control in Insecticide Plants. Arch. Environ. Health
30:441-448, (March) 1965.
4. Ely, T. S.,. MacFarlane, J. W., et al: Convulsions in Thiodan
Workers. J. 0cc. Med. 9:35-37, (February) 1967.
5. Tabershaw, I. R., Cooper, W. C.: Sequelae of Acute Organic
Phosphate Poisoning. J. 0cc. Med. 8:5-20, (January) 1966.
6. Wasserman, M., Wasserman, D., et al: Long-Term Studies on Body
Reactivity in a Pesticides Plant. md. Med. 30:35-40, (December)
1970.
7. Milby, T. H., Samuels, A. Ji; Human Exposure to Lindane:
Comparison of an exposed and unexposed population. J. 0cc. Med.
13(5):256—258, 1971.
8. Mikhailova, G. G.: Contamination of the Air in Storehouses with
Chemical Poisons and the State of Health of Workers. Gigiena
Truda ± Prof. Zabolevaniya 15(5):ll-14, 1971.

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91
THE INVESTIGATION OF A FIELD PROBLEM
OF AN UNKNOWN ETIOLOGY
EARL EDSEL MOORE
This paper will be primarily directed to pesticide—environmental incidents and
situations, but occasional reference will be made to pesticide human exposure
considerations.
The safe and proper use of pesticides is of major interest to everyone and especially
to those State and Federal Agencies with pesticide regulatory responsibilities.
These agencies must deal with a multitude of situations that may involve contaminated
foods, goods, environmental or other detrimental conditions. It is, therefore,
imperative that swift and proper action be implemented to adequately safeguard public
health and for the preservation of a quality environment.
The proper documentation of pesticide accidents and incidental contamination, as a
result of faulty or indiscriminate use, can serve as a useful basis for developing
preventive measures in pesticide use considerations. The facts uncovered by a
thorough investigation of a pesticide oriented problem can be translated into vigorous
educational programs.
Numerous incidents and dilemmas occur yearly in which a pesticide is implicated or
suspect. There may be accidental human exposures, occasionally resulting in death,
crop damage, fish and wildlife kills, a contaminated water supply, a contaminated
livestock feed, and many other related incidents.
It should be clearly understood there is no magic formula in conducting field investi-
gations that would apply to all circumstances, as there are too many variables and
possibilities. For instance, the investigation of a pesticide human exposure would
aecessitate a different approach than, perhaps, an environmental occurrence. However,
there are certain basic principals that can be observed and applied when a pesticide
is implicated or suspect.
A thorough epidemiological investigation should determine the who and what was
involved. The who (host) may be man, animals, wildlife, water supply, crop, etc.,
and tt e responsible agent (what? pesticide), and the environmental situation which
may have contributed to the occurrence of the incident, (such as pesticide misuse,
improper protective clothing, runoff in a water supply, spray drift, or whatever the
case may be).
Proper evaluation of the information gathered in an investigation can serve as an
instrumental tool in developing programs to abate reoccurrences.
The have been eniployed very effectively for decades by public health agencies in
the ci’. tro] of ommunjcable diseases, foodborne outbreaks, epidemics, chronic disease
an ethers.
it is most essential to understand that all pesticides are toxic chemicals and, by
n ces icy, ar poisonous in order to kill pests. They are capable of producing
illness of varying degrees and even death to man, animals and wildlife when indiscrim-
inately used. The extent and severity of morbidity or mortality will depend on
numerous factors, including the toxicity of the pesticide, route of exposure (oral,
dermal, respiratory), the susceptibility or sensitivity of the person (s), animal (s),
or wiLdlife involved and others. Individual reactions will also vary depending on
cn i ir. .mcnL m1 ficcors such as temperature, humidity, and diet, and intrinsic factors
sucL ‘ agc, race, sex, physiological activity, subclinical pathology, fatigue, etc.

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In simple terms, this implies all living creatures possess a different sensitivity
level as to the degree of exposure that produces or constitutes illness or death.
In retrospect to these variables, trends are somewhat apparent In most human or animal
poisonings or environmental investigations. The time interval between exposure and
the onset of symptoms (the incubation period) is generally short. Naturally, this is
much more pronounced where humans and animals are involved. By the same token, a
defoliant herbicide drifting on a tobacco or tomato field would produce adverse
effects rapidly.
The manifestation of most acute exposures to humans will produce symptoms within a
few minutes (there are, of course, exceptions, for Instance Paraquat, a defoliant
herbicide has an incubation period of 7 to 21 days). As expected, a concentrated
solution will produce clinical symptoms more rapidly than a diluted one, and an oral
exposure will generally produce earlier signs than a derinal exposure.
An investigation of a human poisoning and particularly, occurrences involving foods
and environmental contamination may necessitate the cooperation of several people
and/or agencies. Most important is the cooperation and support of a competent
toxicology laboratory that has the capability to perform pesticide residue detection.
Most investigations, especially those of an environmentally oriented nature, will
require the collection of samples for analysis, for without adequate sampling of
specimens and a reliable analysis very little may be accomplished.
Considerations in Conducting Pesticide Field Investigations .
Perhaps, one of the most important points to emphasize is the investigation should be
Inaugurated as soon as the incident is reported for several reasons:
1. This practice may enhance an opportunity to witness the actual condition (s)
or situation. For instance, spray drift from an airplane may have caused crop
damage and of less significance than reported. There: may be other extenuating
circumstances to the problem.
2. Presents a better opportunity of gathering all the details encompassing the
incident. Memories are often short and important points may be overlooked
should sufficient time elapse.
3. In the event the Incident warrants ti e collection of environmental sample (s),
it is likely the sample (s) will be of more value than if a significant amount
of time has elapsed. The situation may be subject to change, depending on the
environmental conditions (there may be instances when the investigator is
handicapped because of delayed reporting). For example, a report is received
that an airplane had sprayed chemicals on a crop near a farm pond and there was
suspicion of drift. There was no visual evidence of fish mortality and
livestock drank the water without Ill effects, yet three weeks elapsed before
the incident was reported. In such instances it may be impossible to establish
a hazardous condition ever existed. This, of course, would be contingent on
the persistence of the chemicals used.
4. The investigation should be detailed and thorough, especially those involving
environmental situations. There may be subsequent legal action and the
investigator may be subpoenaed to testify in court and the report of the invest-
igation (or portions) may be introduced as admissible evidence in the proceedings.
The investigator should be generally acquainted with state laws and regulations
applicable to pesticides. The investigation should reveal any infractions that
may have occurred. For instance, a custom applicator may be involved in an
incident and it was determined he was not properly licensed.

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93 -
5. When determined applicable, camera snap shots, preferably color slides (Polaroid
may be suitable in certain situations) are an excellent illustration of property
damage and actual conditions at the time of the investigation.
6. The investigator should always be prepared to collect samples for pesticide
analysis if applicable. It may be feasible to determine the necessity at the
time of reporting and the appropriate tools and type of containers required for
collection. This would depend largely on the nature of the incident. Samples
for analysis should never be accepted from an unauthorized person or agency.
(They would not be acceptable should legal proceedings subsequently develop).
The laboratory should be alerted that samples may be collected for analysis in
order to acquire the results as soon as possible following submission of
samples. The important point is that samples should be collected and analyzed
as soon as possible. This can be accomplished if the investigator goes prepared
and communicates with the laboratory.
The investigator may find it desirable to attempt to determine the agent (Pesticide)
involved or suspected at the time of reporting. This would present an opportunity to
become familiar with the classification and toxicity and other characteristics of the
chemical,such as persistence, which may be of value in conducting the investigation.
For example, a farm owner reports an aerial applicator sprayed mosquitoes with
Malathion near his farm pond and two weeks later the fish suddenly died. The invest-
igator then should consider and look for other causative agents because Malathion has
a low order of toxicity and is nonpersistent.
What then, is the type of information to be documented and what should the investi-
gator look for, questions to ask and data to record? This is somewhat dependent on
the nature and severity of the incident. It is likely environmeqtal incidents will
require a more comprehensive investigation and consequently, the discussion is
directed accordingly. Reports should be written promptly, and the investigation and
occurrences should be listed in sequence. The development of a form or format in
collecting the information would be helpful.
This is not construed to be a complete listing nor necessarily in order of priority.
1. Record the date of occurrences of the incident, the exact time it is reported
and by whom, their phone number and address. Request specific directions to
the scene to prevent any unnecessary delay.
2. Contact the local health agency or other state or federal agencies that may also
have some responsibility to the problem (transportation spillage accidents, fish
kills, contaminated food moving in jnterstate commerce, etc.). In certain
instances, when a causative agent is suspected and represents a detrimental
effect, the investigator should be prepared to advise a quarantine (pending on
investigations and a laboratory analysis of samples), provided, the person
reporting the incident has the authority to invoke such action to abate further
contamination or hazardous conditions.
3. After arriving at the scene, should more than one individual be acquainted or have
knowledge of the incident, interviewing all connected persons should enhance a
better representation of what developed and transpired. Secure names, addresses,
and phone numbers, as it may be necessary to re—establish contact at a later
date to clarify a point. -
4. Describe the nature of the problem and record the environmental situation (s)
encompassing the incident. (If applicable).

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5. Attempt to determine the source of contamination and the causative agent (s) as
soon as possible. This may be very important in preventing further possible
detrimental effects. Appropriate specimen collection apparatus should have been
brought along.
6. For on—the—farm problems (such as a livestock kill, crop damage, or contaminated
feed stuffs) record the pesticides or toxic agents that have been used recently
and last date of application, rate and method application. It may also require
securing similar information from a neighbor (s) to determine who is at fault.
7. The evaluation of habits of pesticide usage, storage, (where and how) and dis-
posal of empty containers may be of value in determining the cause of the
Incident and possibly where the fault lies.
8. In instances when a pesticide is suspect or implicated, record name of pesticide,
formulation, active ingredients, manufacturer, size of container, amount used.
This will be Important in checking for cross contamination and also, perhaps,
for checking proper Instate registration. A copy of the label of the actual
container may be helpful. Secure a copy of invoices, bill of lading, or any
other document which may be associated with or conceivably have bearing on the
incident.
9. List species of animal (s), wildlife, crop Cs), or portion (s) of the environ-
ment affected. Record the visible effects as they exist and are observed.
.10. Record route of exposure to animals or wildlife (dermal, oral, respiratory) and
directly or Indirectly such as an application or consumption of contaminated
goods.
11. Record time lapse between exposure and onset of symptoms in case of crops when
damage began to appear in hours, days, etc., and the duration of exposure,pro—
vided this can be validly established.
12. In instances involving animals and wildlife, record the number affected, number
expired, and number recovered.
13. Treatment (if any, what and by whom).
14. Upon conclusion of the investigation, should the investigator consider it
necessary and has the authority, quarantine action should be inaugurated to
prevent any further detrimental effects to public health or the environment
(if not previously accomplished).
There will be other details dependent on the occurrence, as there are a multitude of
variables and each occurrence in all probability will be somewhat different, nor will
particular situations require collection of all of the suggested data. It should be
emphasized that often the investigator fails to document sufficient detailed inform-
ation when conducting the initial investigation, usually necessitating a return visit.
Since conditions are subject to change, it is Imperative to conduct a thorough
investigation on the initial visit.
The proper samp’ing of specimens for pesticide analysis Is extremely important, for
without a representative sample Cs) collected In the proper amount, in the prescribed
manner, and the appropriate container, it will be of little value. The source of the
problem may not be determined. In fact, the success of the investigation may impinge
on the samples collected. Only brief reference is made to specimen collection as
“Sampling Procedures’ 1 are scheduled for discussion later in the course.
1. All specimens should be placed in chemically clean containers provided by.the
testing laboratory. (Never put spedimens for pesticide analysis in plastic
containers). If applicable, use chemically clean tools (scoop, bucket, cup,
etc.) in collecting the specimen (a).

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95
2. The sample should be representative of the contaminated media.
3. All samples should be properly identified.
4. Provide the laboratory analyst with a brief resume of the incident and, if
possible, a clue to the pesticide (s) to analyze for. Remember, the analyst
does not have the benefit of the knowledge of the investigator.
5. Submit the samples as soon as possible after they are collected. Residues are
subject to degradation the rate of which is dependent on the pesticide involved.
To emphasize the value of gathering detailed information and drafting a comprehensive
report, the following are reports of two actual investigations illustrating the
importance of many points that have been discussed. These may also serve as an aid in
conducting investigations of a similar nature.
ABSTRACT OF A FIELD INVESTIGATION TO LOCATE
A CONTAMINATED DAIRY HERD AND
ISOLATE SOURCE OF CONTAMINATION
This is an account of an investigation and subsequent developments of an actual
occurrence to locate a dairy farm producing a contaminated milk that was being shipped
interstate to the Cincinnati, Ohio Milk Shed in April 1969 and to isolate the source
of the contamination. The names and firms of those involved in this investigation
have been excluded.
The investigation reflects a sequence of events by both the Food and Drug Adminis-
tration and the Kentucky State Department of Health.
On April 2, 1969, the Cincinnati Regional Office of the United States Food and Drug
Administration notified the Kentucky State Department of Health that a violative
level of Dieldrin (a toxic chlorinated hydrocarbon insecticide) had been detected in
a sample of large curd creamed cottage cheese, manufactured by a local firm. The
discovery occurred as a product of the Food and Drug Administration’s Established
Routine Food Basket Survey and Surveillance Program (compliance of permissible
pesticide residues in foods). A Food and Drug Official disclosed the detection
occurred on March 16, 1969, and that subsequent investigations revealed the source of
contamination was. fluid milk originating from a route that involved 12 Central
Kentucky milk producers. Furthermore, a Food and Drug Administration Inspector had
been dispatched to begin sampling individual producers on the route on March 31 to
determine the source (s) of contamination.
On April 3, a State Department of Health Investigator,accompanied by the milk hauler
covering the route, began sampling of the 12 milk producers on the route,in a
cooperative effort with the Food and Drug Administration, to determine the source (s)
of contamination. The samples were submitted to the State Department of Health
Pesticide Laboratory for analysis the same day.
While collecting the milk samples from the 12 farms, a detailed inquiry regarding
pesticide usage on the farms during the last year indicated there did not appear to
be any mJ.suse or faulty storage.
Meanwhile the Food and Drug Administration had advised the Cincinnati Department of
Health of the problem. The Kentucky Statfe Department of Health, the Food and Drug

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Administration, and Cincinnati officials collaborated, and accordingly placed the 12
farms under official quarantine, preventing further shipment and sale of the milk
either interstate (March 31) or intrastate (April 2).
In the late afternoon of April 3, Food and Drug Officials notified the State Depart-
ment of Health that samples collected by their field inspector from the milk producers
were free of contamination except one. The sample was from a producer with a 105 cow
herd. A few feed samples collected on the farm on March 31 by the Food and Drug
Administration were reported void of contamination. Thus, the contaminated herd was
isolated.
The quarantine on the remaining 11 herds was rescinded on the evening of April 3 by
the State Department of Health.
Due to the high level of Die ldrin in the milk of the affected farm, the investigator
revisited the farm on April 4 to sample all feeds in inventory, water, and forage to
which the milking herd had been exposed, to determine the source of contamination and
prevent further contaminations. The samples were submitted to the State Health Depart-
ment Pesticide Laboratory the same day. During the revisit, the proprietor of the
farm reiterated that neither Dieldrin or Aldrin (metabolized to Dieldrin by the human
and animal body) had been used on the farm, and that pesticide application was accom-
plished by a custom applicator on crop land far removed from areas in which the
producing animals had access.
Furthermore, the investigator was advised that the farm had purchased 35 head of dairy
cattle and most had been incorporated into the milking herd about February 28.
The milk samples collected on the 3rd by the investigator were reported to be free of
contamination, except one, by the State Health Department Pesticide Laboratory, which
contained a comparable level of Dieldrin (as reported by the Food and Drug
Administration).
The herds were segregated on April 5 to determine the feasibility of the new herd
being the contaminating source. A composite sample from each group revealed the level
to be comparable, indicating that either or both a feed item or water must be the
contributing source.
On April 15, the laboratory reported all feed, water, and forage samples collected on
the farm were void of any Aidrin or Dieldrin contamination. Subsequent milk samples
from the combined herd on April 10 and 11 revealed the level of Die ldrin to be
declining, indicating the animals were not being subsequently exposed. Consequently,
it could be concluded that a contaminated feed must have been fed prior to March 31,
1969 (the day the Food and Drug Administration collected samples of farm feeds, etc.).
The milking ration for the dairy herd was prepared on the farm and numerous ingred-
ients were purchased from several sources and rather frequently, in fact, all of the
raw ingredients sampled on April 4 had been in inventory for 10 days or less (except
a small quantity of ear corn purchased in Indiana). These were transported to the
farm in the farm truck.
During a revisitation to the affected farm on April 16, the proprietor of the farm
disclosed the source of two of the raw ingredients (bagged soy bean and cotton seed
oil meal) was purchased from a local grain firm that retailed and warehoused pesticide
products. This was not the case with the other two sources of ingredients. It was
suspicioned that possibly as a result of faulty warehousing or handling that raw
ingredients purchased from the firm may have been accidentally contaminated. An
inspection of the facilities failed to indicate this feasibility.
The visit and inspection, however, proved to be valuable. The manager of the firm
disclosed that the affected farm had purchased a quantity of feed oats for incorpor-
ation in the milking ration, but from another local grain supplier that was the low

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97
bidder. Furthermore, the oats had been purchased prior to the detection of the con-
taminated milk by the Food and Drug Administration.
A visit with the manager of the local firm, reportedly supplying the oats, verified
the purchase but that the firm had acted only as the intermediary in the transaction.
Three hundred bushels of oats were purchased on February 28, 1971 from a Louisville
based grain elevator, delivered the same day to the affected farm in a truck owned by
the local firm. The purchase invoice, however, bore the name of the local firm.
Returning to the farm late the 16th, the proprietor admitted that mention of the oats
had been overlooked during the initial investigation. The oats had been incorporated
into the milking ration beginning about March 3 and the supply exhausted about
March 25th. Furthermore, it was believed none of the oats remained in inventory,
however, an inspection revealed there was some eight to ten bushels in the storage
bin.
A representative sampL from the lot was collected and submitted to the Kentucky
State Health Department Laboratory and subsequently, reported to contain a violative
level of Aidrin. Thus, the contaminating source was officially isolated by the Health
Department on April 28, requiring some 24 days (April 4 — 28) in the process. Hence,
the initial and subsequent investigatiQns were an important basis to determine the
actual period of contamination of the herd (March 3 through March 25), and the amount
of contaminated milk that was marketed. The time period of March 4 (in all probabil-
ity when the Dieldrin began to appear in the milk) and March 31, when the quarantine
became effective. It was calculated some 108,000 pounds of contaminated milk were
marketed (27 days, herd average 4,000 a day).
Since the oats contained a violative level of Aldrin, and also subject to provisions
of the Kentucky Food, Drug and Cosmetic Act, further investigation was required.
An investigation of the originating source of the oats, a Louisville grain elevator,
was begun on April 28. Approximately 10,600 bushels were in inventory and were
promptly placed under quarantine. Officials of the firm believed the 300 bushels
purchased by the affected farm may have been a part of approximately 30,000 bushels
of oats that had been received between February 11, 1969 and April 1, 1969. The oats
were procured from a grain elevator in Indiana and reportedly came from several
growers over a multi—state area prior to and during the time period specified above.
Nineteen thousand bushels of the lot had been sold almost exclusively to three
poultry farms in North Carolina and Georgia. Other than the oats in question, less
than a hundred bushels had been sold locally.
Representative samples from six bins from which oats were stored were collected and
submitted to the State Health Department Pesticide Laboratory for analysis. On May 5,
the Pesticide Laboratory reported the oats to be void of contamination. Consequently,
it was impossible to establish what portion of the 30,000 bushels were contaminated.
Because of elapsed time between purchase of the oats by the affected farm and
detection as the contaminating source (February 28 through April 28), Food and Drug
Administration Officials in North Carolina and Georgia (which had been alerted on
April 28) disclosed that interstate investigations did not uncover any contaminated
oats. Adulterated foods or feeds moving in interstate commerce are the responsibility
of the Food and Drug Administration.
The quarantine on the oats in inventory was rescinded on May 5 by the State Department
of Health.
The affected farm was required to destroy the milk produced from the herd covering an
84 day period (March 31 through June 22) or until the level met the zero tolerance
established by the Food and Drug Administration. The milk producer experienced a
substantial loss during this time period which amounted to approximately $24,000.

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Since the State Health Department investigation revealed the farmer was not at fault,
because of faulty use or storage, he was eligible for restitution for a portion of the
loss through a federal government disaster program. Additionally, the Cincinnati Milk
Shed absorbed a portion of the loss, however, combined, both were not sufficient to
account for the entire loss suffered by the producer.
The producer subsequently instigated legal proceedings against the local grain firm
and the Louisville grain elevator for restitution for the remainder of the loss of the
milk.
Council for the defendants reviewed the dossier of the investigations, laboratory
analysis, and all other pertinent information encompassing the incident. The attorney
disclosed the evidence would disfavor his clientele in court. Consequently, the
deficit, (some $1,650) was remunerated to the milk producer.
An experimental trial coordinated by the Department of Animal Science, University of
Kentucky, of feeding phenobarbital and activated carbon, was apparently effective in
accelerating removal of Dieldrin in the 105 cow dairy herd.!’ 1 The herd was divided
into two groups. After one week of treatment, residue had declined about 64% compared
with 36% for the control group. The time during which the milk had to be withheld
from the market was shortened by at leas.t one month for the treated group.
AN ABSTRACT OF A FIELD INVESTIGATION TO DETERNINE
THE CAUSATION OF MORTALITY IN A BEEF HERD
During the late afternoon of August 19, 1970, the Director of the Kentucky State
Department of Agriculture’s Diagnostic Laboratory notified the Kentucky State Depart-
ment of Health that a small Western Kentucky beef cattle producer had mysteriously
lost 14 head of breeding stock in less than a 24 hour period. Additionally, the herd
veterinarian was unable to establish the cause for the sudden mortality which occurred
on August 18. However, the veterinarian felt a toxic material was involved after
performing an autopsy. Furthermore, there was suspicion that a stream running through
the farm from which the allimals drank was contaminated with a pesticide.
The affected producer disclosed in the investigation Instigated on August 20, that on
checking the herd on the morning of August 18, ten animals were found dead in the
pasture field, four were very ill, eight others appeared to be slightly ill, and the
remainder appeared normal. They were droopy, lethargic, generally weak, ata cia, and
had diarrhea. It was reported the other sick animals died later bn the 18th and had
tremors and muscle twItching In addition to the above symptoms. According to the
owner, a treatment of atropine sulphate wa administered by the herd veterinarian
which is the treatment or antidote for poisoning by organo phosphate and carbamate
insecticides. However, the ill animals failed to respond, and it was later discovered
that this was an improper treatment. It could not be determined what effects, if any,
this constituted to the other recovering animals.
The owner disclosed that pesticides had not been applied to any fields or forage (the
only diet) to which the animals had been exposed. Samples of forage from the pasture
field and from the suspect stream were collected for pesticide analysis. Adjoining
farm owners, with cattle drinking from the same stream, reported no sick animals or
losses.

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99
An inspection of pesticide storage on the affected farm revealed a few pesticides
which were occasionally used on field crops, mainly tobacco. A half gallon container
of Toxphene was noticed, which no longer is recommended for tobacco. The owner dis-
closed that the insecticide was purchased on August 15 from a local firm for the
purpose of spraying the cattle for fly control, and had used Toxaphene for several
years without any ill effects. Less than a quart had been used, and he was sure this
was not the causative agent.
The cattle had been congregated on the 17th, however, 12 were not sprayed because of
darkness. Ill effects were not noticed until the next day and because of the illness
and death in the herd, the owner decided not to spray the remaining cattle.
The owner stated he had followed label directions on the Toxaphene container with the
exception of incorporating approximately a half gallon diesel fuel with the spray
mixture to enhance the residual period (only water was recommended).
The supposedly diesel fuel had been poured from an unlabeled one gallon, brown colored
glass container. However, an inspection did not reveal the type of odor or exact
appearance.
A sample was collected from the Toxaphene container to analyze for possible cross
contamination as a result of faulty man.ufacturing. Samples were also collected of
the spray mixture remaining in the spray tank, the one gallon container, and specimens
from two organs of one of the expired animals.
The animals were quarantined pending laboratory analysis to determine the causative
agent. This was a safeguard to prevent ill animals from being marketed.
On August 27, the Pesticide and Chemistry Laboratories reported the samples of forage
and water were void of contamination and the Toxaphene was not cross contaminated.
Furthermore, the spray tank sample and especially the gallon glass container (suppos-
edly diesel fuel) contained high levels of arsenic. The tissues also contained a
lethal level.
It was subsequently established that Sodium Arsenite was the pesticide in the unlabel-
ed glass container.
The spray solution apparently caused skin irritation, consequently, the cattle licked
their coats ingesting lethal levels of the arsenic containing compound.
In a later discussion, the owner denied purchasing the pesticide, much less storing in
an unlabeled container. Furthermore, that he had personally procured the gallon of
diesel fuel and put in the unlabeled cont iner and stored in the exact location as the
contaminated container. The owner declared since sodium arsenite was found someone
had maliciously switched c9ntainers.
The fact remains, had the farm owner strictly adhered to the label directions, the
incident would not have occurred. The loss of the cattle was estimated at $4,000,
indeed an unfortunate and expensive mistake. Since the incident was a result of
misuse, the producer was not eligible to receive restitution from any disaster
programs.
REFERENCES:
1. Braund, D.G.; Langlois, B.E.; Conner, D.J.; Moore, E.E.; Feeding Phenobarbital
and Activated Carbon to Accelerate Dieldrin Residue Removal in a Contaminated
Dairy Herd, Journal of Dairy Science, Vol. 54, No. 3, Pages: 435—438.

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101
SAMPLING PROCEDURES
Bill L. Stevenson
To promptly and accurately evaluate chemical pesticides in biological and
environmental media, suitable representative samples of these systems
insure quality analytical performance.
The identification and evaluation of pesticides present in samples sub-
mitted to a laboratory may serve as a basis for the documentation of an
accident or incidental contamination from normal use. Laboratory data
is a necessity to identify current and potential public health problems
and protect the environment from unanticipated contamination.
Data from a competent laboratory based upon improper sampling can lead to
false conclusions concerning the pesticide profile of the sample even
though properly analyzed. For example, let us assume that a laboratory
making routine blood ana1ysis of the general population in a given area
is consistently, but erroneously, finding higher pesticide levels than
is being reported by similar laboratories in other areas. Plotted on a
national scale, it would then appear that the people of this area are
being exposed to higher levels of pesticides than the rest of the national
popul ation.
Another example can be cited which involved complaints filed by several
women employees making draperies for mobile homes that some irritant was
present in the atmosphere. An investigation was made and a survey of
the work area revealed that the entire operation, including the storage
of bolts of drapery cloth, was confined to a room 12’ x 15’ with a 3/4
ton air conditioner providing the only ventilation.
Through a literature review, it was learned that formaldehyde is used
to make colors “fast” in the dyeing process of cloth. This information
indicated a possible source of the problem.
The sampling procedure followed (to determine exposure•levels to atmo-
spheric formaldehyde in work areas) was recommended by an excellent and
authoritative sour ce. However, one small but important detail was omitted
in the sampling instructions—-th at was to use an impinger with a diffusion
attachment to disperse the air stream into tiny bubbles for greater ab-
sorption in the collection media. This omission resulted in a false
reading indicating a safe working environment when in fact, the formal-
dehyde vapors exceeded established threshold limits. A law suit was
instituted and was an embarrassment to all concerned.
Interferences are encountered in most analytical methods; therefore, it
is rare that a method is free from all interferences regardless of the
concentration of chemicals in a sample. Nevertheless, most methods will
yield reliable results with little interference when followed as pre-
sented by authoritative and approved methods.

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Analytical procedures are usually designed either to give the total amount
of an element present in a sample or to give the amount of a certain
definite solute species. Interferences affect either type of analytical
procedure and the results are a serious potential source of error against
which the analyst must always be aware.
The following general rules for sampling can be utilized in most investi-
gations: 1
1. Never take a composite sample unless the subject area to be
sampled is known to be uniformly contaminated.
2. Take a number of samples from the subject area that would best
represent possible areas of contamination.
3. Take the samples immediately, when reason for concern is
apparent. It may be too late - later.
4. Label the samples with all the information immediately. You
may forget later.
5. Preserve the samples with whatever means are necessary. This
may be refrigeration, freezing, formaldehyde or solvent.
6. Make sure the means of preservation is compatible with subse-
quent analysis. Samples of crab eater seals and penquins from the
Antarctic were shipped back to this country wrapped in plastic. As
a result the reported levels of DOT are questionable due to the plas-
ticizer in the plastic. Don’t preserve samples to be used for
chlorinated hydrocarbon analysis with chloroform. Don’t preserve
samples for phosphate analysis with formaldehyde. If you don’t
know what analysis will be required, refrigeration is your best bet.
7. Take a large enough sample. Tomorrow will be too late to get
more.
8. Be prepared to take samples. Have sampling tools needed, knives,
scissors, trowels, spoons, etc. Have suitable bottles for samples.
9. Label all samples.
10. Write a description of the situation as the investigator sees
it at time of sampling. It is not’unusual for the cost of analysis
in particular investigations to run $10,000. This expenditure should
not be jeopardized because the sampler is too lazy to write down
the situation as he sees it. Provide a case history. This is
needed for the chemist to get a clue as to what to analyze for.
He cannot possibly screen for the million or so compounds that
presently contaminate our environment.
11. Get samples to laboratory now. Don’t wait two weeks while
you talk the situation over.
Procedures for taking samples :
Although pathologists should have adequate knowledge concerning the col-
lection and submission of autopsy samples for chemical analysis, occa-
sionally samples are contaminated by u9ing improper containers or solu-
tions that interfere with analytical methods.

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103
Samples from suspected human poisonings :
1. Quantity:
a. Tissue — 1—5 grams
b. Vomitus - 2 ounces or more
c. Stomach content - 2 ounces or more
d. Stomach wall tissue - 5 grams or more
e. Kidney - 1-5 grams
f. Liver - 1-5 grams
g. Blood - 5-10 ml
h. Urine — 5-10 ml
i. Brain — 1-5 grams
2. Packaging: Each tissue sample should be isolated in a separate
chemically clean glass jar or bottle.
3. Shipment: It is preferable to have the samples frozen and shipped
on Monday to the appropriate laboratory. When samples are frozen,
care should be taken that enough dry ice is included to insure
arrival of samples in a frozen condition.
Soils : The area should be searched carefully for oil spots or areas
that look different from the surroundings. These can be sampled by
using a sampling tool made from a tin can or similar container. Cut
both top and bottom out evenly. Wash well and repeatedly. Rinse in
clear water. Press this can in suspect area to depth of 1-1/2 - 2 inches
and remove from soil. Punch core taken into new quart mason jar. Take
several more cores from same areas. Seal jar and send to the laboratory
after careful marking to indi 9 te where sample was taken, when, by whom,
and number and depth of cores.
Water : Water samples should be submitted in chemically clean one-gallon
glass bottles.
Most natural water bodies are not completely homogeneous, and obtaining
a truly representative sample will depend on the sampling technique
employed, as well as the size and number of samples collected.’ Proper
sampling of large bodies of water should include a surface sample, an
intermediate sample and a bottom sample. Always use chemically clean
glass bottles for collecting samples.
Interfering elements are leached from plastic; therefore, plastic sample
bottles should never be used to collect samples for pesticide analysis.
Swab Samples : Sampling to determine contamination on a wall or duct or
other surfaces may be collected through the use of sterile wool, some
medical alcohol or acetone and plastic throw away gloves. Wearing the
gloves, wash the suspect area with swabs of cotton and solvent using
care not to let solvent squeeze out of the swab. Place used swab in pint
mason jar. Repeat on adjacent area. When labeling bottle,record wh re
sample was taken, by whom, how it was sampled and how large an area.
The following tables provide information for proper sample collection;
i.e., size of sample, packing storage, preservatives and other helpful
information)

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104
BIBLIOGRAPHY
1. Barthel, W. F., Sampling Procedures for Chemicals in the Environment,
Atlanta Toxicology Branch, Division of Pesticide Comunity Studies,
Environmental Protection Agency, Chamblee, Georgia.
2. Brown, Eugene; Skougstad, M. W. and Fishman, M. J., Methods for
Collection and Analysis of Water Samples for Dissolved Minerals
and Gases.
AIR SAMPLING
Sampling of air requires sophisticated equipment and methods. Consult
State Services Section for information.
OTHER SAMPLING
Many other types of sampling are occasionally required such as grain,
feed, flour, food or other types of samples representing human or animal
exposure. It is highly important in such cases to inspect carefully the
material to be sampled in order to detect possible areas of contamination.
Sometimes only one sack in a shipment will show an oily spot of contami-
nation, or the colored grain denoting seed treatment. Samples should be
drawn both from suspect and non-suspect areas and so labeled. If in
doubt, call the appropriate laboratory for guidance.
LABELING AND SHIPPING
Without proper labeling or shipping, all the care and trouble of taking
the samples is wasted. Be sure the label is explanatory and well
attached . Ship samples on a Monday so that they arrive during the week
and not over the weekend where they might sit in a hot airport terminal
and deteriorate. If the samples are worth taking, they are worth packing
well and witht i iet1eaextra dry ice or other refrigerant.

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105
Attachment A
Tj ’pe Poison Examples Types of Samples Needed
Chlorinated Aldrin Stomach and its content,
hydrocarbons Dieldrin vomitus, kidney, liver
DOT and fat.
Endrin, etc.
Fluorinated 1080 Stomach and its content,
compounds Sodium fluoride or vomitus if present,
liver, kidney and heart.
Inorganic Zinc phosphide Stomach and its content,
phosphides vomitus, liver and spleen.
Organic TEPP Stomach and its content,
phosphates Parathion, etc. vomitus, brain, heart, blood
(if not deteriorated).
Phosphorous Elemental phosphorous Stomach and its content,
vomitus, liver and kidney.
Cyanide Cyanogen Stomach and its content,
Sodium cyanide vomitus, throat tissue,
heart, brain and lung tissue.
Alkaloids Strychnine Stomach and its content,
vonitus, liver and kidney.
Thallium Thallium sulfate Stomach and its content,
vornitus, liver, kidney,
leg muscle and bone.
Cardiac Red squill Stomach and its content,
glucosides vornitus and a portion of
intestine.
Lead Lead acetate Stomach and its content,
Lead arsenate vomitus, liver, kidney, and
long skeletal bones (leg).
Anticoagulants Warfarin Stomach and its content,
Pival vomitus, heart, liver and
PMP blood.
Diphacin
Miscellaneous poisons, Stomach and its content,
toxic compound unknown vomitus, heart, liver,
kidney, brain, blood and
bone.

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TABLE I Environmental Sampling
SAMPLE SIZE OF SAMPLE PACKING* STORAGE PRESERVATIVE OTHER INFORMATION
SAMPLING OF WATER FOLLLRING INCIDENT
private well 1 gallon glass ambient none description of well
date
municipal 1 gallon ea. glass ambient none note where and when
pre filter taken
at filter
treated
river 1 gallon- glass ambient none detailed location of
sampling site and date
lake 1 gallon glass ambient none detailed location of
sampling site and date
Accompanying each set of samples should be a complete description of incident and all
pertinent information to guide laboratory director in making analysis.
SAMPLING OF TISSUE AT AUTOPSY
fat 1 to 5 gms glass bottle frozen or 10% Formaldehyde name of subject
or aluminum site of sample
foil sample size
date, cause of death
liver 1 to 5 gms glass bottle frozen not acceptable name of subject
lung or aluminum name of tissue
brain foil sample size
gonads date,
spleen cause of death
muscle 1 etc.
* Where glass containers are specified they should be fitted with teflon or aluminum lining.

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TABLE I Environmental Sampling (Cont.)
SAMPLE SIZE OF SAMPLE PACKING STORAGE PRESERVATIVE OTHER INFORMATION
SAMPLING OF BODY FLUIDS
urine 25 ml of 24 hr. glass ambient 1/10% name of subject
for chlorinated sample if possible Formaldehyde description
hydrocarbons whether 24 hr. or not
urine for **25 ml of 24 hr. glass frozen none name of subject
phosphates sample if possible description,
whether 24 hr. or
not.
blood for 1-5 ml plasma glass tube frozen none name of subject
chlorinated oxaloted reason for
hydrocarbon analysis
date, physician
blood for 1-5 ml whole blood glass tube frozen none name of subject
phosphates oxaloted reason for analysis
date, physician
blood for 1-5 ml plasma glass tube refrigerated none name of subject
cholinesterase heparinized reason for analysts
date, physician
1-5 ml red cells glass tube refrigerated none name of subject
heparinized reason for analysis
date, physician
** A complete case history should be provided with all human samples.

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TABLE I Environmental Sampling (Cont.)
SAMPLE SIZE OF SAMPLE PACKING STORAGE PRESERVATIVE OThER INFORMATION
OTHER SAMPLING
soil 1 lb. glass or ambient none description of site,
metal can amount sampled,
by whom and why.
sediment 1 lb. glass or ambient none description of site,
metal can amount sampled,
by whom and why.
wildlife 20 gins muscle glass frozen none detailed description
birds (20 gins fat if of sampling site
mammals possible) name of animal
or reptiles approx. age if known
by whom and why.
fish 20 gnis tissue glass frozen none detailed description
of sampling site
name of animal
approx. age if known
by whom and why.
Analysis of one animal, fish or bird will generally tell but little. Enough animals should be sampled to
provide a crossection exposure picture of the incident but certainly never less than 10 subjects.

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DEPARTMENT OF HEALTH. EDUCATION. AND WELFARE FORM APPROVED 109
PUBLIC HEALTH SERVICE BUDGET BUREAU NO SIMYUI4
HEALTH SERVICES AND MENTAL HEALTH AOMtN 1STRATIQM
NAYIONSL. COMMUNICABLE DISEASE CENTER
PESTICIDES BROGRAM
ATLANTA, GEORGIA 30333 i. 0 1 009 87
COMMUNITY STUDIES PROJECT ON ?ESTICIDES
ACUTE EXPOSURE RECORD
PARTICIPANrS NAME
RTICIPANTS ADDRESS r, fude zip code)
2. PROJECT CODE S —— 3. GROUP 10 —
4. AMA ID
EMPLOYER’S ADDRESS (include zip code)
(D060) i URBAN 2CRURAL 3OUNKNOWN
DATE OF BIRTH PHONE SEX RACE
—I ——I ——
5. INTERVIEW DATE
——I —
-- IARITAL STATUS:
I Married 2 Widowed fl Divorced 4 fl Single
PLOVER
INTERvIEWER’S NAME
.
8. SOURCE OF DATA: I 0 Participant 2 Employer ReI Pive
4 Other (II other than participant, give name)
CURRENT OCCUPATION: CODE
(INDEX II
(Dolo) —
NUMBER OF YEARS — — (Report to nearest year)
CHIEF OMPLAINT; (D020/
(Mark (x) by any sympIoms which occurred as port of the chieF comp laint.)
CODE
o o none II coma, unconsciousness 22 D palpitations
01 malaise 120 skin flv hing 0
020 oIigue 130 increased sweating 240 vomiting
030 ConfuSiOn ‘40 cyanosis 250 abdominal pain, cramps
04 Tjheodache 150 blurred vision 26 [ diarrhea
05 nervousneSs 16 increased tearing 27 0 muscular weakness
04 E hyperirrrt biIity 17 rhinitis 2e tremors fascuculations
07 j Iight.he d dnesi nasal stuffiness 29 convulsions
os fainting 190 increased saliwotian 300 poresthesioe
09 dizziness 20 tightness in chest 3t fl other (specify)
— to ‘dermatitis 2IT difficult breathing 32 —1 fever
- PRESEN1 iLLNESS
Ii. CASE TYPE: ‘1) ’ 3O) (Mark (x) in block by appropriate answer)
1 Accudeitot4,ome 3 0 Accidental-occupational Homicide
— 21 Nonccci dontal-occuparionol 4 Suicide or attempted suicide 6 Other
12. DATE AND PERIOD CF EXPOSURE: (DOlO)
began (date) ......,_(t ,rnej Use 24 hour clock)
ended (date)
Ii. SUSPECT ED AG ENTIS): (1 st chpmico! names f pesticides and solvents. ((only brand name .s available, record and look up
— chemical name later.)
NA
ME
EDST
LIQUIO , ETC
CODE
(INDEX liP
AFPROX. AMOUNT
(IF INGESTED
fDOSOj _I__/______ mgm
____ / /_ — _____________________
_/__/___ mom
____ _// m m
____ _/__/_•_ ,_ mgm
_!_—_/
____ , . _ / 1 1 1
• I 554 cNC Ci
P 5. 5. PAGE I OP 4 PAGES

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110
14. PROBABLE MAIN ROUTE OF EXPOSURE: (ttt160) (Mark (x) in block b y appropriate answer)
1 0 oral 2 E deimol °0 inhalation
15. PHRASE WHICH BEST DESCRIBES SOURCE OF AGENT
1 C unknown or not applicable 4fl chemical token from work
26 bought in store ¶‘i chemical token From elsewhere
0 bought from door to-door salesman € applied by commercial firm
0 kitchen
C ba’hroom
S closer
8 garage, shed, dc
7 C other t soecify —
x) in blo:lc by appropriate answer)
0 applied by other person
8 6 provided by employer for ob
g Q other
C
eQ below ground or floor level
9 —4 Feel above ground or floor level
to ‘Q 4.—R feet above ground or Floor level
ii 9+ feet above ground or floor level
18. WHICH CIRCUMSTA .CES CONTRIBUTE TO PESTICIDE INTO’(ICATION IN Tn ! OCCUPATIONALLY-EXPOSED ? tii”J;
Mcr (x) (a’ irems h,ch beer describes. (USE ONLY!F QUESTION 71 A3QVE INDICATES OCCUPAT)Q?IAL, CASE TYPE)
1 ‘ unknown
2,_, spillage
3 equipment molFjncrian
6 poor ventilation of work environment
19. WHICH CIRCU?1STANC!S CONTRIS
(THIS IS TO BE FILLE D OUT l i i EVER
I unknown
2 — ate or drank from cOnta iner
3 ate bait
. 1 o’e conrcT.,naied soil
UTE TO P
YINSTANC
ESTICIDE INTO (ICATIOrI’ £fljO, ‘.io’k (xJ for rems w ich best
a 1
C handled conra’nina’ed obtec: i s ;. gloe) (specify
0 exposed to conr:’ninved so I a: iv ter
io other derrnal source ‘soaci 1 y
I I - inhalation when foam or 53n9 1 rubber furniture was ardent
esc- a
)
)
S drank conirni’ e’ed water
other oral source scecfy
7 handled con lamer or pesticide
2 inholatio , —he change in ambient temperature was
) (specify —___________________________________________________________
causally
related
I
130 other inhalation tzpecify
20. DID THIS PAT iENT TAKE ANY OF THE FOLLOWI IG DURING THE LAST WEEK’ b129j i Yes 2 No 3 Unknown
yes, nr a - k i J in box by000raaric’e ire—s bela e, a’td pro. ide ‘equas’ad inorrnorron)
NAME
,
OUANTITY’UNITS.
FREQUENCY l RSI
OATEA’2O Tn ’! TA< N
MO . DA
TIME use 2 3 hour clack
alcohol
I
1 ( 1 (2 1 1 ‘___,
iVl2J) - . I —
i1) (21t —
IPl_ IHJ - — — —
1O!25)( I — — — —
(111261 /
‘in.’ : -, . __ :
sedor,uet
narcoi.cs
i
bra’ i .a:ine cna
!arbcflate irsrmç
!
[
I.
—
21. $0. 1 LONG MAD PESTiCIDES SEEN AVAILABLE AT EXPOSURE SCENE’ [ i lum
nor caplmccble r unknown 6 days C months
2 rr hours 4 0 weeks : years
or other
(()00) (Mark
16. WHICH BEST DESCRIBES CONTAINER’ ‘I)080j (Mark (x)
by one •tern from each column) -
A
B
I j original container, labeled
4 Q paper sock or bag’
20 original container, unlabeled
7 plastic sock or bag
oilier con’oiner, unlabeled
a bottle
a ether container, mislabeled
9 can or drum
other (soctcif,.,
I
c’other fsoecify —
C locked
2 __ unlocked
17. WHICH BEST ESCR13ES STORAGE AQEA AT HO’-IE OR AT PLACE WHERE POISONING OCCURRED’ ‘ØIIiQ) wa k x i i i
one box in each co)ymn. U5E ONLY’F DUESTION II ABOVE IN DICATES HQIdE CASE TYPEI
A B
s poor applicaiion techniques, or poor work practices
a d,ift
7 too early ra-en lsy after fumigation
B ‘ intention& (specify
9 C other # _ .r
1
d.mS I ‘55-4 iNcoc
fly ses
PAGE 2 OF & noes

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IN USE DURING THIS EXPOSURE: (D140) (mark Cx) in block by approp.answer
+Elrubber boots tJrubber suit
D long sleeves 9 go.ggles
6 0 coveralls 10 other (specify
7 apron
30 none
01 j malaise
02 , rotigue
03 confusion
04 ‘ heada:he
05 _ nervousless
06 hyporirritcbility
07 light-headedness
08 fainting
09 dizziness
10 dermatitis
II coma, unconsciousness
12 skin flushing
13 increased swec:,ng
14 U cyanosis
iS bIurred vision
16 increased tearing
17 rhinitis
lB i nasal st ffness
19 increased salliction
20 tightness itt chest
21 ‘ d ff,c lt bre thing
22 palpitations
23 nausea
24 J vomiting
25 : abdominal pain, cramps
26 D diarrhea
27 j muscular weakness
28 tremor, fosciculations
29 convulsians
30 porestkes.ae
31 Ti other (specify
32 (ever
PROTECTIVE MEASURES
0 none
2 U rubber gloves
D mask Or respirator
type
23.
WHICH OF THE FOLLOWING FIRST-AID MEASURES WERE INSTITUTED IMMEDIATELY’ (b!Ji))
—
5 bath or shower
2 change clothes 6 El vomiting induced (method
3 El wash exposed area with soap and water 7 gave antidote (specify
4 iT wash exposed a-ca with other sot vent
24.
HOW MANY HOURS ELAPSED BETWEE 1 E.CPCSURE AMO 9 GINNIN OF COMPLAINTS’
(1)160) (DI6 1)
25.
HO?) MANY HOURS HAD COMPLAINTS BEEN APPARENT D FORE MEDICAL ATTENTION
RICEIVED’
(l)1 ’O, ‘D!7))
25.
WHAT CCMPLAINTS (SY’4PTC s ’S) OTHER THAN THOSE IN THE CHIEF CCMPLAI T WERE ASSOCIATED WITH THI$
ILLNESS’ ‘1) 180)
TREAT 1ENT AND CLINICAL COURSE ‘presert
:!Inessl
27.
NAME OF ATTENDING
PHYSICIAN
MD
PHYSICIAN’S ADDRESS
(,rclude
zip code)
29.
NAME OF HO5PITAL
‘lo.
doys
hospitati:ed
lDt O)
30.
TREATMENT
EXAMPLE:
Trec -,e,r is pre r—ed to in:lude the usual s poc ”ve mcosures such cs oi-v y,osycen, necessary ‘/ fluids, ec. t -lence rhase r ’eed n:i
be ri ’cn?,oned _r!ess their c—ilssian lies conrr:bijie t rhc course. The rn dic,r ShDUd include all pertilent ones, but sin d scs of
aspirin, etc. may be omitted.
The physician need not detci! cccli siig!e dose os o, ‘ndi.idual listing. othe,, eac” cliangc i- schedule sio_d be noted The ‘esponsc
b i oi:’e’ clinico! or p” iocoIogicol cn s( ’oud be eesc-icr,v ror .?’ ‘ cn o ‘oi.,c 1 u ; ent , f r CtCoe.
‘/ EOiCINE
(IN x IIt i DOSAGE
[ AMOij ’JT
RESPC’ SE
Atro ine
Atraoine
2-PAM
J ._ I 0.8 mgm IV q mitt
._!_.i. 0 8 mgm IV q 1 hr
1 gm IV slowly
x8
x r
6 4 rlgn
3.2 mgm
1003 0 mg ’
pulse, d,tatea pupils
recovered conscIousness
no clinical,
MEoic:t ’ tE
— DOSAGE
—
RES°O ,SE
—
i b.2Ofls
——
——
——
J ——
—
mgnt
———— ._ing- ——
mgr-

mgrn.

—_____
——
-_________
——
a is I I 5 ..i i’.coz
as.. t..i
PA3 •

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3I. OUTCOME:
(0210) I 0 latal
Parathion
Porathon
PNP
PNP
AGENT
CODE
(INOE II)
SOURCE
CODE
CONCENTRATION
UNITS
METHOD
(0230)
,,
, /
,,
,,
,,
,
,,
/1
.
ppm
ppm 1
ppm
ppm
ppm
ppm
ppm
ppm
ppm
34. HAS SUBJECT HAD A PREVIOUS EPISODE OF PESTICIDE POISONING? (D240) I Dyes 2 no 3 unknown
(if yes, give dote, etc., below)
(D241)
——I ——
——
Has PHS 1.165-4, ACUTE EXPOSURE RECORD, been completed for eoch episode’
V.a No
t
I 0 0 * 11 PHS 1.155-4 has not been completed
2 0 complete one now.
ifl 2
aS. WERE OTHER WORKERS OR FAMILY MEMBERS ALSO EXPOSED OR ILL? (D250) i Yes 2 No
How mony —— (Give details below) -
2 fl recovered
3 0 residual damage
AGENT
32.
FINAL
DIAGNOSIS:
(0220) t
pesticide intoxicatiOn
2 0 solvent intoxiCatiOn 3 drug intoxication a other
33.
CONFIRMATION OF
ETIOLOGIC
AGENT:
r X AMPLE
CODE
IINOEX uII
SOURCE
LI LA _I
.LI _1l
.9_i2_.i_i 478
/1L/_LL!
CODE
Container
Vomitus
Serum
Urine
CONCENTRATION
ilPJITc
1-
2
3
METHOD
5000
500
2
45
ppm
ppm
ppm
opm
EC
U/v
Eli iO?t
Elliott
36. CONCLUDING REMARKS: (0260) i

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PESTICIDES IN FOOD AND FEED 113
L. L. Ramsey
Perhaps, it would be illuminating to look at major historical
developments to see how we arrived at this point in pesticide regula-
tion and then to conclude with a review of FDA’s pesticide residue
findings in food.
1906 — The Food and Drugs Act of 1906
The administration of this Act was lodged in the old Bureau of Chemistry
of the U. S. Department of Agriculture. The Act contained no authority
for establishing pesticide residue tolerances.
The Act required the Government to “establish that the added poisonous
or deleterious substance may render the article injurious” before it
could take action against a shipment of food bearing excessive pesticide
residues.
1910 - Federal Insecticides Act of 1910
This Act coveted only insecticides and fungicides and was intended to
protect the farmer against adulterated and fraudulent products.
1927 - The regulatory functions of the Bureau of Chemistry were separated
from the research functions and the Food, Drug, and Insecticide Administra-
tion was created to administer the Food and Drugs Act of 1906 and the
Federal Insecticides Act of 1910.
1920 - 1939 - A period of zealous regulatory action against shipments of
fruits and vegetables containing excessive residues of lead, arsenic,
and fluoride, particularly during the 30’s. The informal tolerances
for spray residues on fresh fruits and vegetables had been reduced yearly
until in 1932 they were set for arsenic at 1.4 ppm; lead, 3.5 ppm;
fluoride, 2.8 ppm.
1938 - The Federal Food, Drug, and Cosmetic Act enacted
This Act contained the so-called poison p se rule: “Any poisonous or
deleterious substance added to any food except where such substance is
required in the production thereof .... shall be deemed to be unsafe . . . .“
The law also provided authority for establishing safe tolerances for
poisonous substances such as pesticides.
1940 - President Roosevelt’s Reorganization Plan
The Food and Drug Administration was removed from the Department of
Agriculture and placed in the new Federal Security Agency. The unit
administering the Insecticides Act was left in the Department of
Agriculture.
1940 - Informal tolerances on apples and pears were raised after a study
by the Public Health Service as follows: arsenic, 3.5 ppm; lead, 7 ppm.
1944 - First legal tolerance established for a pesticide residue at 7
milligrams fluorine per kilogram on apples and pears.
1945 - Informal tolerance for DDT set at 7 ppm on apples and pears.
1946 - Court decision held the tolerance for fluorine to be null and void
because the residue was actually cryolite, not fluorine.

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1947 - The Federal Insecticide, Fungicide, and odenticide Act was enacted
This Act was designed to exercise more effective control over pesticides,
particularly the new organic pesticides which were proliferating. The
Act requires label registration of these pesticides moving in interstate
commerce, the registration being based upon data showing that the pesticide
is effective for the control of pests and safe when used in accordance
with directions on the label.
1950 - The Delaney Committee hearings on pesticides and food additives.
1950 - FDA spray residue hearings with respect to fresh fruits and vegetables.
1954 - The Pesticide Chemicals Amendment (The Miller Amendment )
Established the present petition clearance procedure for setting tolerances
for pesticide residues on raw agricultural commodities. This was the first
pre-testing, pre-clearance procedure for chemical agents used on food. It
shifted the burden of proof. The industry was required to show that the
pesticide was safe before it was used instead of the Government being
required to show that the pesticide was unsafe after it had been used.
1955 - Tolerances on fresh fruits and vegetables established for a long
list of pesticides based on the 1950 spray residue hearings.
March 25, 1955 - Tolerances for residues of sesone established at 6 ppm
on potatoes, peanuts, peanut hulls, peanut hay and at 2 ppm on asparagus
and strawberries, the first tolerances under the Miller Amendment.
Additional tolerances for other pesticides have followed to date.
1962 - Silent Spring by Rachel Carson contributed greatly to a general
public awareness of the pesticide problem.
1963 - A Science Advisory Committee appointed by President Kennedy largely
because of the furor created by Silent Spring issued a report entitled
“The Use of Pesticides.” The Committee recommended among other things
that the concepts of zero tolerance and no-residue be reviewed, that the
accretion of pesticide residues in the environment be reduced by orderly
means, and that the elimination of persistent pesticides should be the
goal.
1963 - Minute residues found in a wide variety of products because of the
use of analytical methods based on gas liquid chromatography which have
a sensitivity several magnitudes greater than the sensitivity of methods
previously employed and provide means of finding metabolic products.
Extensive regulatory action was taken against milk; cauliflower; dairy
feed, such as alfalfa, corn silage,’and dried sugar beet pulp; and other
food crops.
October 13, 1963 - The actionable level for DDT residues in milk was reduced
from 0.1 ppm to 0.05 ppm for DDT and fc r dieldrtn and heptachior epoxide it
was set at 0.01 ppm and the states were notified.
May 1, 1964 - Interdepartmental Agreement
An agreement entered into voluntarily by the Departmerrts of Agriculture,
Health, Education, and Welfare, and Interior for the purpose of coordinating
the activities of the three Departments pertaining to pesticides. This
Agreement implemented one of the recommendations of the PSAC report of
May 15, 1963. -

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115
April 13, 1966 - USDA and HEW published a joint statement of implementation
of the report of an NAS-NRC “zero committee.” Where there was any reasonable
expectation of residue, however minute, the USDA would not grant a pesticide
registration until the Food and Drug Administration had established a
pesticide residue tolerance. The rather formidable task of converting a
large number of label registrations by USDA based on no residue to label
registrations based on a negligible residue tolerance got under way and
still continues.
1967 - Tolerance established at 0.05 ppm for residues of DDT, TDE, and DDE
singly or in combination in fluid milk pursuant to a report of a Scientific
Advisory Committee dated October 26, 1966.
1968 - DOT tolerances lowered to levels no higher than necessary to
cover residues incurred in good agricultural practice.
1969 - Tolerances for other pesticides reduced or proposed for reduction
including captan, folpet, and TDE. Seizures of Coho salmon because of
high levels of DDT.
In addition to the PSAC report of 1963, to which I alluded a few
moments ago, there have been a number of other reports by nationally
recognized advisory bodies. These reports are all directed toward a
sound national policy on pesticides, and thus worthy of our consideration.
1. Ribicoff Report of July 21, 1966.
Senator Ribicoff served as the chairman of Senate Subcommittee.
The Report of this Subcommittee is well balanced. It recognizes the
valuable role the newer chemical pesticides have played in the improvement
of agricultural production and in the furtherance of public health and it
recognizes the dangers to our overall environment as suggested in Miss Carson’s
popular book Silent Spring . In a section headed “The Benefit-Risk Equation”
it is stated that “the committee found no reliable evidence to suggest that
the benefit-risk equation was presently unbalanced in any significant way.”
However, the Report goes on to warn that more information is needed to
guarantee future balance of the benefit-risk equation and to assure public
confidence. This Report included a comprehensive series of recommendations.
2. Whitten Report, 1966.
Congressman Whitten served as the Chairman of a Subcommittee of the
House. This report notes that the book Silent Spring by Rachel Carson
influenced the concern of the public over the use of pesticides and points
out the unwarranted implications in this book. In general, the report
is not critical of the use of pesticides; no recommendations were made.
3. The NAS-NRC Report on Persistent Pesticides, May 1969.
In the preface the Committee refers to the PSAC Report of 1963 and
notes that progress has been made but expresses concern about what remains
to be done and about gaps in knowledge of pesticides. The Committee
declares “.... there is an immediate need for world-wide attention to
the problem of buildup of persistent pesticides in the total environment.”
The principal recommendation of the report is “that further and more
effective steps be taken to rethite the needless or inadvertent release
of persistent pesticides into the environment.”

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4. HEW Report of the Secretary’s Commission on Pesticides and Their
Relationship to Environmental Health, November 1969.
November 1969 - HEW Report of the Secretary’s Commission on Pesticides
and Their Relationship to Environmental Health.
While the Commission found itself in agreement with this rather broad
and general recommendation of the NJIS-NRC Committee on Persistent Pesticides,
it concluded that the value of this recommendation would be considerably
enhanced if it were made somewhat more specific and spelled out in greater
detail. Toward this end, the Commission directed a number of specific
recommendations carefully weighing the benefits of modern pesticide usage
against the possible risks to man’s health and the quality of his environ-
ment. In all, the Commission made 14 specific recommendations, but I
believe that only three are of sufficient interest to this audience to be
mentioned at this time.
III. Eliminate within two years all uses of DDT and DDD in the
United States, excepting those uses essential to the preservation of human
health and welfare and approved unanimously by the Secretaries of the
Departments of HEW, Agriculture, and Interior.
IV. Restrict the usage of certain persistent pesticides in the United
States to specific essential uses which create no known hazard to human
health or to the quality of the environment and which are unanimously
approved by the Secretaries of the Departments of HEW, Agriculture, and
Interior.
V. Minimize human exposure to those pesticides considered to present
a potential health hazard to man.
Besides these there have also been the reports of congressional hearings
on specific aspects of our pesticide problem, such as the Fountain Committee
hearings; all of these have exerted an influence on the pesticide policy
of the Federal Government.
On December 2, 1970 the President’s Reorganization Plan No. 3 became
effective. This plan created the Environmental Protection Agency and
transferred the responsibility for establishing tolerances for pesticide
residues on raw agricultural commodities and processed food from the FDA
to the new agency. FDA will continue with its pesticide tolerance en-
forcement program as well as its monitoring program for pesticide residues
in food.
In conclusion, our over-all basic problem in the pesticide area is
to decide what actions should be taken consistent with a policy that will
keep the benefit-risk equation in balance, because the safety of any
pesticide usage is not absolute regardless of the quantity of favorable
data that may have been adduced. There is always some risk, be it ever
so slight, and thus the benefits that may accrue from the usage of any
pesticide must be weighed against the risk to be incurred.

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117
SELECTED STUDIES PESTICIDES IN FISH AND WILDLIFE
Thomas W. Duke
Pesticides and possibly polychiorinated biphenyls (PCBs) are affecting our nation’s
fishery resources. Seafood products were seized on at least two occasions in 1969
because of high residues of pesticides and oyster and clam beds on the eastern hore
of Virginia were closed temporarily because of potential contamination from DDT.’
Fortunately, the occurrence of high levels of pesticides in seafood organisms is rare,
but law levels of these chemicals (lower than levels considered to be harmful to human
health) and PCBs continue to appear in oysters, shrimp, fish, and other estuarine
fishery organisms. Although these low levels are not considered to be harmful to
human health, we do not yet know precisely how they affect the organisms in which they
occur.
Much research effort is being devoted to determine the fate of pesticides and PCBs in
the estuarine environment and the effect of these chemicals on estuarine organisms.
Fate or occurrence is observed through monitoring programs whereby organisms, sediment,
aniwater are collected and analyzed for the desired chemicals. Information obtained
from the monitoring program is used to design laboratory experiments to determine
effects of environmental levels of the chemicals on organisms. For example, investi-
gators at our laboratory, in cooperation with National Marine Fisheries Service
Laboratory (N.M.F.S.) at Galveston, Texas, examined a limited number of shrimp from
Galveston Bay, Texas for chlorinated hydrocarbons on a quarterly basis in 1969 (1).
They found DDT in hepatoparicreatic tissue in samples taken in the summer. In labora-
tory experiments to test the effect of these environmental levels of DDT on shrimp,
some test shrimp died of DOT poisoning. Since DOT was localized in the hepato-
pancreas of the shrimp from Galveston Bay and this organ is discarded when shrimp are
prepared as seafood, these shrimp would have been satisfactory for human consumption
according to existing regulations. However, if the residues were representative, the
population was endangered at this particular time because of the effect of DOT on the
shrimp. Fortunately, subsequent samples of shrimp from Galveston Bay contained little
or no D1YJ .
Pesticides can reach estuaries through run-off from agricultural areas, direct appli-
cation for noxious insects and municipal and industrial effluents, but PCBs are
generally considered to be industrial pollutants. A correlation between application
of DOT to farmland and occurrence of the chemical in oysters was shown (2). A
similar correlation was evident when DOT was applied to beaches to control the stable
fly. Instances of local pollution by industrial and municipal effluents also were
recorded. No apparent correlation exists between pest control programs and occurrence
of PCBs but at least one industrial source has been located (3). Although major
sources of organochloride pesticides and PCBs may differ, their chemical structure
and potential danger to estuarine organisms are similar.
‘Coho salmon from Lake Michigan
Canned mackerel from California
2 National Fisherman, October 1970

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Pesticides and PCBs can be classified according to their chemical structure. The
chlorinated hydrocarbon pesticides such as DDT and its inetabolites and dieldrin are
persistent, insoluble in water but soluble in lipids whereas the organophosphates are
less persistent and often hydrolyze in seawater. PCBs r semble DDT in structure and
are chemically inert, non-volatile compounds. Aroclors R (Monsanto Company Trademark)
are mixtures of PCBs that vary in position and number of chlorine atoms. Aroclor
1254 and 1260 (54 and 60 percent chlorine by weight) have appeared more often than
other Aroclors in our monitoring samples. An excellent description of structural and
physical properties of PCBs has been presented (4).
Pesticides entering an estuary can be concentrated through bioaccumulations, sorption
to sediment particles and detritus and by chemical precipitation; conversely, these
chemicals can be diluted and dispersed through mixing and transport with tidal
currents, co-distillation, and emigration of animals that have accumulated the
chemicals (Figure 1). Animals can accumulate and concentrate pesticides in their
tissues and some animals serve as biogeochemical agents in the estuary. For example,
shellfish can remove particulate matter from sea water and deposit the matter in
pseudofeces and feces on bottom sediments. Mussels are important in the estuarine
phosphate cycle as a depositional agent - extracting particulate phosphorus from sea
water and making it available to deposit-feeders (5). Perhaps populations of shell-
fish could act in a similar manner with pesticides by filtering pesticide-laden
particles from the water and depositing them on the bottom. This action would tend
to conserve in the estuary pesticides that otherwise could be transported to sea.
Pelagic animals, however, can transport pesticides out of the estuary as they emi-
grate. Croakers leaving Pensacola Bay, Florida, transported one-half pound of DDT
and its metabolites from the bay to the Gulf of Mexico (2).
Fate and Effect of Pesticides
Results of various monitoring programs give us some indication of the fate of pesti-
cides that reach the estuarine environment. Residues found as part of N.M.F.S.’s
national monitoring program have been summarized and discussed (6). Levels of
chlorinated pesticides in oysters and estuarine environment of the Mobile Bay, Ala-
bama area have been reported (7) and also levels of chlorinated hydrocarbons in
organisms from estuaries in California (8). Residues of pesticides in some estuarine
fish over a 3-year period (9) and pesticide levels in fish of the Northeast Pacific
(10) were recorded.
Recently, our laboratory participated in a cooperative monitoring study with N.M.F.S.
laboratories in La Jolla, California and eatt1e, Washington to determine residues of
chlorinated hydrocarbons in certain commercial species that inhabit Pacific coastal
and off-shore waters. Since we were interested in residues recently accumulated by
the fish, livers were analyzed as indicator organs. The livers were prepared and
analyzed by standard techniques used for tissue from other marine organisms (11).
Residues of DIY.F and its metabolites in the liver of selected fish from the Pacific
Ocean are presented in Table 1. Levels of these chemicals in the mackerel can be
considered “background” and occur in many species analyzed at our laboratory. How-
ever, the lack of detectable amounts ((0.01 ppm) in salmon and the extremely high
levels in rockfish are exceptional. The salmon were in the fifth-year class and had
been out of fresh water for two or three years. Although residues were lacking in
the liver, other tissues and organs, such as fat and ovaries, could have contained
stored DDT. High levels of DDT in the bottom-feeding rockfish alert us to the need
for further examination of this species and its environment.

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rable l.—-Rasiduei of DDT and Metabolites in Composite Samples of Fish Livers from Pacific Ocean’
Date
Collected
in-d-y
Location
No.
in
of Livers
Composite
Sample
DDE
DDD
DOT
ug/kg
(ppm) Wet
Weight
Total
Sockeye Salmon
(Oncorhynchus nerka) 2-23-70
49 ’16’N, 161 ’44’W
10
2
N.D.
M.D.
M.D.
--
2—27—70
51 ’30’ —52 ’30’N
160°O0’W
10
M.D.
M.D.
M.D.
--
2—28-70
5230’N, 160 ’OO’W
10
M.D.
M.D.
M.D.
--
Jack Mackerel
(Trachurus s, tricus) 5-7—69
3l 25’N, 12159’W
2
0.092
0.019
M.D.
0.11
5-25—70
Carter Bank
17
1.0
0.12
0.30
1.42
5-27—70
6 tat. W. of Mission
Beach Jetty, San
Diego, Celifornia
10
2.5
0.16
0.61
3.07
Rockfish
(Sebastodea miniatus) 5-13-70
Santa Monica Bay
10
141.
9.
12.
162.
(Sebastodes pauciepinia)5-13 —70
Santa Monica Bay
9
510.
33.
48.
591.
(Sebastodes constellatus) 5-13—70
Santa Monica Bay
5
900.
56.
70.
1026.
‘Salmon were collected and processed for analysis by personnel from National Marine Fisheries Service
Laboratory, Seattle, Washington; Jack Mackerel and Rockfish, by National Marine Fisheries Service
Laboratory, La Jolla , California. Analyses were performed at the Environmental Protection Agency,
Gulf Breeze, Florida Laboratory under the supervision of A. J. Wilson, Jr., Chief Chemist.
2 N. D. Not detectable ((.01 ppm)
Table 2.--Accuinilation of Aroclor 1254 by Eatuarine Organisms (Jack I. Lowe, Unpublished Data)*
Animal
Size
Average
Duration
of Test
(Days)
Concentration
of Aroclor in
Test Water
(ppb)
Conc. in
Living
Animals
(ppm)
Cone.
Pactors**
Mortality
( )
Temp.
. ‘)
Salinity
.)
Oyster
(Craeaostrea
virginica)
Mult
(2 - 3”)
9
28
.
14
5.0
26.0
5200
0
Shrimp
(Penaeus
duorarum)
Juvenile
19
31
20
5.0
. 33.0
6600
72
Fish (Spot)
(Lejostomus
xanthurus)
Juvenile
(1-1/4”)
9
28
21
5.0
120.0
24000
50
“
Juvenile
(1—1/4”)
15
27
19
5.0
.
46.0
9200
50
II
Juvenile
(1—1/4”)
15
27
28
1.0
17.0
17000
17

Protection Agency, Gulf Breeze Laboratory, Gulf Breeze, Florida 32561
**Amount of Aroclor 1254 in animal (vet weight tissue )
Amount of Aroclor 1254 in water
119

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120
Pesticides introduced into an estuary enter the biogeochemical cycles that are in
operation within the estuary; therefore, we should evaluate the effect of these
chemicals at the ecosystem and population level as well as the species level. Un-
fortunately, little information is available on the effect of pesticides on eco-
systems. Observations were made on the effect of a herbicide, Dichlobenil, on the
primary producers in a small (0.15 ha.) pond (12). About 1 month after treatment,
the dominant hydrophytes in the pond suffered a definite decline. All of the Chara
vulgaris and 807. of the Potamogeton pectinatus were eliminated. The number of blue-
green algae increased as the hydrophytes were eliminated. The ecosystem regained its
original balance of plants in about 4 months. A striking effect of environmental
levels of DDT on a population of seatrout was reported recently (13). Residues of
DDT in the yolk of speckled seatrout, Cynoscion nebulosus , were correlated with
regional declines in productivity of this species. Recent data indicate that the
fishery may be recovering from the pesticide stress. To my knowledge, this is the
first documentation of the effecto environmental levels of pesticides on an
estuarine fishery.
Pesticides entering the food web of an estuary can move from plants to animals to
]arge animals as the organisms eat and are eaten. Green plants occupy the first
trophic level; plant eaters or herbivores such as zooplankton, and some fish and
mollusks occupy the second level; and carnivores such as large fish form the third
and possibly a fourth.
Only a few selected research projects will be presented in the following discussion.
Reviews are available in the literature pertaining to pesticides in the estuary (14),
(15), (16).
Pesticides can affect the capacity of phytoplankton to photosynthesize and these
minute plants can also transfer accumulated pesticides to herbivores. Studies of the
effect of 17 toxicants on five species of algae showed the toxicity of DIYI varies
with the solvent used and 5 ppm lindane had no effect on any of the species tested
(17). In another experiment, Chlorella sp. rapidly took up DDT labeled with carbon-
14 (18) by absorption. Concentrations of DOT in the parts per billion range reduced
photosynthesis in laboratory cultures of four species of coastal and oceanic algae
(19). Laboratory experiments have shown partition coefficients (weight concentration
factors) for DDT of 2.5 x io for Syracosphaera carterae and Thalassiosira fluviatilus
and 8.0 x l0 for Ainphidinium carteri (20). Investigations of the effects of sub-
lethal concentrations of urea herbicides on the total protein, carbohydrate, chloro-
phyll, and carotenoid content of six genera of unicellular algae were conducted at
this laboratory (21). Low levels of certain herbicides decreased growthcf the algae
and decreased carbohydrate content but produced no effect on protein content.
Brine shrimp ( Artemia ) and copepods are often used in laboratory experiments as
representatives of the second trophic level. An example of the effectof DDT on the
reproductive capacity of Artemia has been demonstrated (22). Second and fourth
generation brine shrimp from populations treated with DDT in 1966 showed no reduction
in reproductive performance. However, residual DDT killed some of the nauplii when
they emerged. Grosch points out that this type of attrition would be very difficult
to detect in nature. Evidently, Artemia also can accumulate DDT in their natural
habitat. Other investigations showed residues of DDT in brine shrimp nauplii from
California and Utah and the nauplii from Utah contained three times as much DDT as

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121
those from California (23). Crabs fed nauplii from California had a good survival
rate and showed no abnormalities, but crabs fed nauplii from Utah suffered marked
mortality and some species exhibited abnormalities. These investigators suggested
that the differences in normality and survival appeared to be related to the DDT
content of the nauplii.
Filter-feeding mollusks can be affected by many of the pesticides in use today and
some of those chemicals are particularly toxic to embryonic development and larvae.
Acute toxicity data obtained with bioassay tests are helpful in illustrating the
relative toxicity of these compounds to oysters. Laboratory studies on the effects
of pesticides on embryonic development of clams and oysters and their larvae indicate
the need to evaluate effects on all stages of the life cycle of an organism (24).
Most of the pesticides tested affected embryonic development more than survival or
growth of larvae; however, some reduced larval growth with little effect on embryonic
development. Anomalies were found in larvae of bay, issel, Mytilus edulis , after
these animals were exposed to 1.5 mg/liter of Sevin ’ (Union Carbide Company Trade-
mark) for 48 hours (25). The need for studies of long-term exposures to sublethal
concentrations of pesticides was demonstrated by investigators at this laboratory,
who exposed oysters for 9 months to a mixture containing 1.0 ppb each of DDT, para-
thion, and toxaphene -- a mixture applied at different concentrations to agricultural
crops in Northwest Florida (26). The test oysters suffered a loss in weight after 6
weeks exposure but the loss did not become significant until after 22 weeks had passed.
After 9 months, histopathological examination of the oysters revealed considerable
pathology that was apparently due to the pesticide.
Fish, as part of the third trophic level, have been much investigated for pesticide
effects, often using death as a criterion for effects. Other criteria that could be
used include behavior and enzyme activity. The capacity of sheepshead minnows,
Cyprinodon variegatus , to avoid selected insecticides and herbicides has been
investigated (27). Test fish avoided water containing DDT, endrin, dursban, and 2,4-B,
but did not avoid test concentrations of malathion or Sevin. ilansen also is studying
the effect of pesticides on the salinity preference of fish. Inhibition of acetyl-
cholinesterase in brains of fish has been used to monitor organophosphorus pesticide
pollution in estuarine waters (28). Organophosphorus compounds inhibit this enzyme
which is essential, to nerve function. Experiments also showed that specific levels of
brain cholinesterase activity relate to extent of exposure and death of sheepshead
minnows for several organophosphate pesticides (29). Thus, the enzyme can be used to
detect these compounds and assess their threat to fish in the environment.
Fate and Effect of Polychlorinated Biphenyls
A series of “unknown” peaks appeared in 1966 in gas chrotnatograins analyzed for chlo-
rinated hydrocarbons in wildlife. Similar peaks were later identified (30) as poly-
chlorinated biphenyls. Since that time, PCBs have appeared in seals and porpoises in
Scotland (31), birds and bird eggs in Britain (32), fish, mussels, and birds from the
Netherlands (33), and from several estuarine areas in the United States (34). Fish and
shellfish from Texas, Georgia, and South Carolina collected as part of BCF’s national
monitoring program also contained residues of these chemicals, including Aroclor 1260
(Butler, unpublished data). 3
3 p. A. Butler, Consultant, Environmental Protection Agency, 106 Matamoros Drive,
Gulf Breeze, Florida 32561

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122
Aroclor 1254, another of the series of PCB compounds, was found in the water, sediment,
and biota of Escambia Bay, Florida (3).
Aroclor 1254 was widely distributed in the bay system. Only one source of the chemical,
an industrial plant on the Escambia River was located, but the chemical occurs in sedi-
ment and in tissues of pelagic and sessile organisms that are widely distributed with-
in the estuary. The widespread distribution is an indication of the extent of bio-
logical and physical transport of the chemical in the ecosystem.
Aroclor 1254 was first discovered in oysters in April 1969 and later appeared in
water, sediment, fish, blue crabs, and shrimp. One sourceof the chemical, an
industrial plant on the Escambia River, was located by analyzing 30 water samples
from Escambia Bay and River. The Aroclor reportedly entered the plant’s effluent
through accidental leakage of a heat exchange fluid. Levels in the water near the
plant decreased abruptly when the leakage was corrected.
Investigators from our laboratory cooperated with representatives from several State
of Florida Agencies, the University of West Florida, and industry to locate and stop
the leakage of the pollutant into the estuary. As in many other instances, this
pollution abatement required a team of the scientific community.
Several bioassay tests conducted in our laboratory to determine the effects of Aroclor
1254 on selected estuarine organisms have shown that under laboratory conditions, this
chemical can be toxic to estuarine organisms (Table 2). Other information on the
toxicity of Aroclor 1254 at concentrations in the parts per billion range to labora-
tory animals has been reported (3), (35).
The potential hazard of PCBs in the environment has been recognized by the Monsanto
Chemical Company. Officials of the company announced recently that sales of PCBs in
the future would be limited to those who could control disposal of the final product.
This should, we hope, reduce future introduction of PCB5 into our ecosystem.
Future Responsibilities
We must continue to monitor estuaries to determine the occurrence of toxic materials
and the effect of these materials on the biota. Such a need was illustrated in the
Report of Committee on Persistent Pesticides, Division of Biology and Agriculture,
National Research Council to U. S. Department of Agriculture (Nay 1969):
“The Committee concludes that there is substantial evidence of continuing
damage in some areas, particularly to fish and birds, by pesticide residues
at present environmental levels. There are examples of concentrations in
food chains at levels that are lethal to predators. Exposure to pesticides
at sublethal levels probably produces more subtle effects, causing changes
in the physiology, biochemistry, or behavior of animals that may be harmful
to the population as a whole. Certain game fish accumulate pesticidal
chemicals by storage in the body and in the fat-rich yolk of egges (sic);
there may be no injury to adult fish, but lethal or harmful amounts are
acquired by the newly hatched offspring when they absorb the egg yolk.
Studies on two continents show that the reproductive success of certain
birds of prey is impaired by DOT and its metabolites, which apparently
act to reduce eggshell thickness and thus to increase premature breakage
of the eggs.”

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I am cautiously optimistic about future uses of pesticides in relation to fishery
resources. I express this feeling on the basis of efforts being made in research,
ongoing programs for monitoring and regulating pesticide usage, industrial concern,
and a growing public awareness of the impact of pesticides on air environment. We
can be optimistic but not complacent.
Acknowledgments
I thank Nary Ruth McCracken for preparing the figure and Dr. Nelson R. Cooley for
critically reviewing the manuscript.
References
(1) Nimmo, B. R., A. J. Wilson, Jr., and R. R. Blackman. 1970. Localization of DDT
in the body organs of pink and white shrimp. Bull. Environ. Contain. Toxicol.,
5(4): 333-341.
(2) Butler, P. A. 1968. Pesticides inthe estuary. Proceedings of the Marsh and
Estuary Management Symposium . John D. Newsoin, Editor. 252 pp. Thos. J. Moran’s
Sons Inc., Baton Rouge, Louisiana.
(3) Duke, T. W., J I. Lowe, and A. J. Wilson, Jr. 1970. A polychlorinated biphenyl
(Aroclor 1254L ’) in the water, sediment, and biota of Escambia Bay, Florida.
Bull. Environ. Contain. Toxicol., 5(2): 171-180.
(4) Peakall, D. B., and 3. L. Lincer. 1970. Polychlorinated biphenyls. Another
long-life widespread chemical in the environment. BioScience, 20(17): 958-964.
(5) Kuenzler, E. 3. 1961. Phosphorus budget of a mussel population. Limnol. and
Oceanogr., 6(4): 400-415.
(6) Butler, P. A. 1969. Monitoring pesticide pollution. BioScience, l9(lO):889-891.
(7) Casper, V. L., R. 3. Hammerstrom, E. A. Robertson, Jr., J. C. Bugg, Jr., and
3. L. Gaines. 1969. Study of chlorinated pesticides in oysters and estuarine
environment of the Mobile Bay area. HEW-PHS Consumer Protection and Environmental
Health Service, Bureau of Water Hygiene, Cincinnati, Ohio, 47 pp.
(8) Modin, John C. 1969. Chlorinated hydrocarbon pesticides in California bays and
estuaries. Pesticide Monit. 3., 3(17): 1—7.
(9) Lyman, L. D., W. A. Tompkins, and 3. A. McCann. 1968. Massachusetts pesticide
monitoring study. Pesticide Monit. 3., 2(3): 109—122.
(10) Stout, V. F. 1968. Pesticide levels in fish of the Northeast Pacific. Bull.
Environ. Contam. Toxicol., 3(4):240-246.
(11) Anas, R E. and A. J. Wilson, Jr. 1970. Organochiorine pesticides in fur seals.
Pesticide Monit. 3., 3(4): 198-200.
(12) Walsh, G. E., and P. T. Heitmuller. 1969. Effects of Dichlobenil upon physical,
chemical, and biological factors in a freshwater pond. Abstracts. 1969 Meeting
of the Weed Science Society of America, p. 92.
(13) Butler, P. A., R. Childress, and A. 3. Wilson, Jr. 1970. The association of DDT
residues and losses in marine productivity. FAO Pollution Conference - Rome,
Dec. 1970, pp. 1-13.
(14) Hayne, B. W., T. W. Duke, and T. J. Sheets. 1969. Pesticides in estuaries. In,
H. T. Odum, B. J. Copeland and Elizabeth McMahan. Coastal ecological systems of
the United States. (An unpublished report to Federal Water Pollution Control
Administration).
(15) Gray, E. E. 1969. Systems with pesticides. In, H. T. Odum, B. 3. Copeland and
Elizabeth McMahan. Coastal ecological systems of the United States. (A Report
to the Federal Water Pollution Control Administration. Institute of Marine
Science, University of North Carolinas Norehead City, N. C.)

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124
(16) Katz, M., D. E. Sjolseth, D. R. Anderson, and L. R. Raylor (Reviewers). 1970.
Water Pollution. In, Annual Literature Review. J. Water Pollu. Cont. Fed.:
983-1002.
(17) Ukeles, Ravenna. 1962. Growth of pure cultures of marine phytoplankton in the
presence of toxicants. Applied Nicrobiol., 10(6): 532-537.
(18) S8dergren, Anders. 1968. Uptake and accumulation of C 14 -DDT by Chlorella
sp. (Chlorophyceae). Oikos, 19: 126-138.
(19) Wurster, C. F. 1968. D]YJ reduces photosynthesis by marine phytoplankton.
Science, 159: 1474-1475. 14
(20) Cox, J. L. 1970. Low ambient level uptake of C-DDT by three species of
marine plankton. Bull. Environ. Contam. Toxicol., 5(3): 218-221.
(21) Walsh, G. E., and T. E. Grow. 1970. Effects of ureau herbicides upon chemical
composition of unicellular marine algae. Abstract. Thirty-third Annual
Meeting American Society of Oceanology and Limnology, Kingston, R. I., August
25—29, 1970.
(22) Grosch, D. 5. 1970. Poisoning with DJY1: second- and third-year reproductive
performance of Artemia . BioScience, 20(16): 913.
(23) Bookhout, C. G., and J. D. Costlow, Jr. 1970. Nutritional effects of Arteinia
from different locations on larval development of crabs. Helgolllnder Wiss.
Meeresunters. 20: 435-442.
(24) Davis, H. C. and H. Hidu. 1969. Effects of pesticides on embryonic development
of clams and oysters and on survival and growth of the larvae. Fish. Bull.,
67(2): 393-404.
(25) Stewart, N. E., R. E. llemann, and W. P. Breese. 1967. Acute toxicity of
the insecticide Sevin R and its hydrolytic product l-napththol to some marine
organisms. Trans. Amer. Fish. Soc., 96(1): 25-30.
(26) Lowe, J. I., P. D. Wilson, and R. B. Davison. 1970. Laboratory Bioassays.
In, Annual Report Center for Estuarine and Menhaden Research, Pesticide Field
Station, Gulf Breeze, Florida.
(27) Hansen, D. J. 1969. Avoidance of pesticides by untrained sheepshead minnows.
Trans. Amer. Fish. Soc., 98(3): 426-429.
(28) Holland, H. T., D. L. Coppage, and P. A. Butler. 1967. Use of fish brain
acetylcholinesterase to monitor pollution by organophosphorus pesticides. Bull.
Environ. Contam. Toxicol., 2(3): 156-162.
(29) Coppage, D. L. 1970. Enzyme systems of estuarine organisms. Annual Report
Center for Estuarine and Menhaden ReSearch, Pesticide Field Station, Gulf Breeze,
Florida.
(30) Jensen, S. 1966. Report of a new chemical hazard. New Scientist, 15 December
1966: 612.
(31) Holden, A. V., and K. Marsden. 1967. Organochlorine pesticides in seals and
porpoises. Nature, 216: 1274-1276.
(32) Holmes, D. C., J. H. Simmons, and 3. OG. Tatton. 1967. Chlorinated hydro-
carbons in British wildlife. Nature, 216: 227—229.
(33) Jensen, S., A. G. Johnels, S. Olsson, and G. Otterlind. 1969. DDT and PCB in
marine animals from Swedish waters. Nature, 224: 247-250.
(34) Risebrough, R. W. 1969. Chlorinated hydrocarbons in marine ecosystems. ,
Chemical Fallout, G. G. Berg and H. W. Miller (Eds.), C.harles C. Thomas,
Springfield, Ill., p. 5-23.
(35) Hansen, D. J., P. R. Parrish, J. I. Lowe, A. J. Wilson, J,i ., and P. D. Wilson.
1971. Chronic toxicity, uptake and retention of Aroclor(!)l254 in two estuarine
fishes. Bull. Environ. Contain. Toxicol., 6(2): 113-119.

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125
Reprinted from the Journal of the Washmgton Academy of Sciences 59, 45 (1969), pp .77—85.
Occurrence and Significance of
Pesticide Residues in Water’
H. Page Nicholson, Ph.D.
Southeast Water Laboratory, Federal Water Pollution Control Administration,
U. S. Department o/ the Interior, 1 lthens, Georgia
Man throughout the civilized world is
rapidly coming to realize Lhat environ-
mental contamination, with its harmful
ecological implications, is a matter to be
taken seriously. I bring to your attention
one facet of environmental contamination;
namely, water pollution by pesticides. It
is but another example of the adage that a
good thing in the wrong place can be
undesirable.
The Problem
Water pollution by pesticides became a
problem in the 1940’s concurrently with
rapid advances in pest control made possi-
ble by the development of new synthetic
toxicants. Many of these synthetics are
remarkably lethal to aquatic forms of life.
Farmers were startled at the sudden loss
of fish in their ponds and streams follow-
ing rains sufficient to cause runoff from
treated cropland (Young and Nicholson,
1951). Aerial applications of DDT to con-
trol forest insects were quickly followed
by losses of valuable sports fish and the
aquatic insects upon which they fed (Hoff-
man and Drooz, 1953; George, 1959).
Today we still experience periodic losses,
but we know considerably more than
formerly about their causes and preven-
tion. We know that sublethal quantities of
pesticides, primarily chlorinated hydro-
carbon insecticides, occur widely and fre-
quently in our streams, lakes, and even
1 Presented at the Entonio ogicaI Society of
America, Southeastern Branch Meeting, Biloxi,
Mississippi, January 27-30. 1969.
in the sea. This occurrence is indirectly
evident through the recovery of residues
from the tissues of fish (Nicholson, 1967;
Anon., 1963), and directly evident by
chemical analysis of water. In an effort to
determine the extent of pesticide pollution
throughout the Uthted States, Weaver et at.
(1965) examined water samples in Sep-
tember 1964 from 56 rivers and 3 of the
Great Lakes. Chlorinated hydrocarbon in-
insecticides were found in 44 rivers and
in Lake Michigan at Milwaukee at con-
centrations ranging from 0.002 to more
than 0.118 gig /liter. Dieldrin was found in
39 rivers and Lake Michigan; DDT, or
its metabolite DDE, was found in 25
rivers; and endrin was found in 22 rivers
and Lake Michigan.
The two principal sources of water con-
tamination by pesticides today are runoff
from the land and discharges of industrjal
wastes. Other causes are (a) activities in-
tended to control aquatic life (plants, fish,
or insects), (b) carelessness and accidents.
Runoff from the Land
Consider first insecticide runoff from
the land. In 1959 my laboratory undertook
to follow the course of water pollution by
insecticides in a single large agriculturs l
watershed over a period of nearly seven
years (Nicholson et at., 1966). We selected
a 400-square-mile cotton-growing area in
northern Alabama in which cotton acreage
varied annually from 13,000 to 16,000
acres. From S to 84% of this acreage was
treated with insecticides each summer de-
pending upon the degree of boll weevil and
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126
bollworm infestation. The quantity of tech-
nical grade insecticides used each year
varied from 12,000 to 140,000 pounds
Toxaphene, DDT, and BHC accounted for
84—99% of all usage.
Water sampling was done nearly con-
tinuously at a municipal water treatment
plant situated at the downstream end of
the river basin. Thus, water samples rep-
resented drainage from the entire study
area. We learned the following:
(a) Insecticides did run off the land.
They entered the river from the
watershed in general, rather than
from a few favorably located cot-
ton fields.
(b) Toxaphene, DDT and BHC vere
recovered in water samples in con-
centrations generally less than 1
ig/l. Highest mean recoveries were
usually made during the summer,
the season of application.
(c) Nearly all water samples contained
insecticides year around dut ing
years of heaviest application. To-
ward the end of two years of
minimal application (12,000 and
14,000 lbs., respectively), the fre-
quency of negative water samples
increased, indicating an improve-
ment in river water quality with
diminished insecticide usage.
(d) Toxaphene and BHC, first and
third in poundage applied, were the
most frequently found in water.
DDT, which constituted 26—35% of
the pesticides used, was recovered
only during the fifth and sixth years
of observation.
(e) DDT exhibited a marked affinity
for sediment, and suspended sedi-
ment was the primary vehicle for its
transport, thus accounting for its
tendency to appear less frequently
in Water. Toxaphene and BHC, in
contrast, were found much less
frequently in association with sedi-
ment and were transported pri-
marily in solution in the water.
A study by Bailey and Hannum (1967)
reported from California sheds further
light on runoff as a means of pesticide
transport. Approximately 20% of all pesti-
cides used in the United States annually is
applied in California. The areas studied in-
cluded the agriculturally important Im-
perial, San Joaquin, and Sacramento Val-
leys, where irrigation is required for
successful farming.
Major
(a)
findings were:
DDT, DDD, toxaphene, heptachlor
epoxide, lindane, dieldrin, and BHC
were found both in surface water
and in tile drainage water in con-
centrations generally less than 1
(b) All aforementioned insecticides, ex-
cept BHC, were found in sediment
and ranged from 1 to 1200 pg/I.
(c) Thiophosphate insecticides, which
degrade more readily, were de-
tected primarily in agricultural
drainage, irrigation wastewater, and
surface water directly associated
with insecticide applications.
(d) Pesticide concentrations were high-
est in agriculturally developed areas
and decrease in surface water in
proportion to inflow dilution and
uptake by sediment and aquatic
organisms.
Manufacturing Wastes
Manufacturing wastes also may contain
quantities of pesticides sufficient to have
a decided impact on water quality. The
types of industries involved include pro-
ducers of basic pesticides, cooperage firms
that reclaim used pesticide drums, and
textile plants that mothproof woolen
yarns and fabrics with dieldrin. These
plants usually have liquid wastes requir-
ing disposal—wastes which frequently con-
tain residues of unrecovered pesticides.
Virtually all of these industrial plants
provide some sort of waste treatment, but
it is not always as effective a& it should
be. Dilution in the receiving stream can-
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1 27
not be depended upon to eliminate the im-
pact of the waste load. Sublethal residues
of chlorinated hydrocarbon insecticides can
undergo a buildup in biotic components
of the receiving water body, and ordinarily
sublethal quantities of organophosphate
pesticides may, through extended exposure,
progressively inhibit the acetylcholines.
terase enzyme to a degree that can kill
aquatic life. Direct and catastrophic
damage also has occurred when in-plant
trouble resulted in an unanticipated slug
discharge of wastes containing concentra-
tions of a pesticide sufficient to be acutely
toxic. An example of such a situation and
its successful management follows.
A plant in Alabama which manufactures
parathion and methyl parathion experi-
enced a breakdown in its waste treatment
facility in May 1961 (Anon., 1961). Proc-
ess wastes were discharged to the sewer-
age system of an adjacent city and ap-
proximately 60% of the combined sewage
and industrial waste was diverted, un-
treated, to a small stream during the break-
down. Fish, turtles, and snakes died along
28 miles of the stream, the average dis-
charge of which at the time was 211 mil-
lion gallons a day at a velocity of three.
fourths mile per hour. The creek entered
the Coosa River the average discharge of
which was then about 28 times greater
than that of the creek. Yet even with that
dilution, parathion residues were recovered
90 miles down the Coosa and some lesser
fish kills occurred in it. After a second
fish kill in 1966, the company constructed
a basin for temporary containment of its
wastes, should another emergency arise.
This simple device, along with the usually
adequate waste treatment normally pro-
vided, should effectively prevent recurrence
of the problems previously experienced.
Accidents and Carelessness
Perhaps the third most significant cause
of pesticide pollution lies in accidents and
accident’s handmaiden, carelessness In-
tensive educational campaigns sponsored
by agricultural, conservation, water-pollu-
tion-control, and public health agencies
and by the agricultural chemicals manufac-
turing industry have reduced the frequency
of such occurrences. Most farmers have
learned that it is inadvisable to dump un-
used spray residue where it might run into
a waterway, and that they should not wash
out spray equipment in a creek. Aerial
applicators now pay heed to the protec-
tion of ponds and rivers. Nevertheless,
some instances of water pollution by pesti-
cides still occur as a result of thoughtless-
ness and accidents. An instance in which
human health was at stake will serve as
an example (Anon., 1964).
In 1964 a rancher instructed his hired
hand to dispose of approximately fifty 4-lb.
bags of over-age 15% parathion dust. Un-
known to the rancher, this was done by
dumping the bags off a highway bridge
into the Peace River one mile upstream
from the municipal water intake of Arca-
dia, Florida, a town of about 6,000 people.
The act was discovered when some boys
fishing near the bridge hooked a bag and
had the foresight to report it.
The town fortunately had an auxiliary
well for emergency use and immediately
reverted to it. The citizens were instructed
not to use the water, and flushing of the
mains was begun. Subsequent analysis of
water samples showed that the parathion
concentration in the distribution system
after flushing was generally less than 1
Lg/l. However, a series of samples taken
from a tap at the local bus station con-
tained amounts up to 380 &g/l.
Investigation revealed thist the bags of
parathion had been dumped in the river
about 10 days before their discovery. The
bags were polyethylene lined and resisted
rapid disintegration. Many were recovered
unbroken and those that did disintegrate
apparently did so intermittently over a
period of several weeks. This may have
been the reason that residue levels suffici-
ently high to be a threat to human health
or the fish in the river did not occur. All
but 8—12 bags were eventually found.
Parathion residue occurred in river water
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128
for about two weeks after discovery at
concentrations generally less than 1 g/l.
Control of Aquatic Life
The chemical control of aquatic weeds,
rough fish, and aquatic insect pests is gen-
erally managed by professionals so that
undesirable consequences are minimized.
A need currently exists for herbicides ap.
proved for broader use in water. A joint
committee of the Departments of the In-
tenor and Agriculture are seeking a solu.
tion to this need. A similar, but remotely
related, source of pesticide residues is
poaching for fish. We still have instances
where insecticides, frequently toxaphene or
DDT, are illegally released in water to
catch fish.
Ground Water Pollution
No broad discussion of this subject
would be complete without considering
ground water. The potential for pesticide
contamination of ground water is very
much less than for surface water. How.
ever, it can occur.
A case is on record in Florida where
the municipal water supply wells of a city
of 25,000 contained low levels of parathion
(usually less than 1 g/l) over a several
month period in 1962.63. The city’s
water supply consisted of both surface
water, which reached the municipal water
treatment plant via a canal from a citrus
fruit producing area, and of five wells
which were located in the vicinity of the
treatment plant. The water from both
sources contained parathion. The wells
were rather shallow—drilled to a depth
of about 100 feet and screened both at
the bottom and at about the 30. to 50.foot
levels. It is speculated that heavy pumping
from the wells drew down surface water
from the canal.
A more serious instance occurred in the
South Platte River Basin near Denver,
Colorado in the mid.1950’s, caused by
seepage of 2,4.D and related compounds
from an industrial waste lagoon (Cottam,
1960). Water from wells in a 6.5.square.
mile area when used for irrigation was
sufficiently contaminated to cause crop
damage.
Eye (1968) concluded after a study of
the physical.chemical behavior of dieldrin
in the soil that residues of this insecticide
cannot be transported in significant
amounts through soils into subsurface
water by infiltration, and therefore they
pose no threat to the quality of ground
water. We have examined many well water
samples from the Southeastern States and
only in a few instances have we detected
any evidence of chlorinated hydrocarbon
insecticides. In those few cases, I recall
only two in which direct contamination
did not seem to be a possible cause. On
the other hand, Bailey and Hannum
(1967) in California reported recovering a
broad range of chlorinated hydrocarbon
insecticides In ihoce I . ,oall . un-
derground tile drains from irrigated crop.
land. They did not speculate on how in-
secticides entered the drains. A possible
route might be through cracks or other
direct passages from the surface.
In several of our mid-western States,
where water of high quality is in limited
supply, consideration is being given to
using runoff water collected seasonally in
playa lakes as a source from which to
recharge ground water aquifers. The Rob.
ert S. Kerr Water Research Center of the
Federal Water Pollution Control Admin-
istration at Ada, Oklahoma, is engaged in
studies to determine the quality of re-
charged water, including the persistence
and distribution of pesticides that may be
contained in such water, after being
pumped into the ground for storage.
Significance
We have seen that water contamination
by pesticides occurs widely and commonly
at concentrations generally less than 1
g/l. Higher concentrations occur inter-
mittently. But of what significance are
such occurrences?
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Aquatic Life
Quite clearly the unintentional killing of
fish and other aquatic life by overwhelm-
ingly lethal concentrations of pesticides is
harmful and undesirable. Occurrences of
this type are generally local, readily ap.
parent, and sporadic, with partial or total
repopulation quickly occurring.
Widespread, long-term, low-level con-
tamination of the environment is much
more difficult to evaluate and is a matter
of growing public concern. It is caused
primarily by a few compounds, members
of the chlorinated hydrocarbon insecticide
group—the so-called “hard” insecticides—
that persist so long in nature and therefore
escape our control after they are applied.
Other pesticides, by and large, either de-
grade with reasonable rapidity or ar so
restricted in usage as to be of less con-
cern except in special cases. One is tempted
to speculate as to whether we would have
had the public ouLcry over pesticides that
we have experienced during the past 10
to 15 years had it not been for these few
“hard” insecticides. I am inclined to think
that it would have been much less ex-
tensive.
The single sublethal manifestation with
chlorinated hydrocarbons that is most ob-
vious, and the significance of which is
least understood, is that of biological ac-
cumulation. Biological accumulation may
occur through direct absorption from the
water or by absorption and passage
through the food chain. The implications
for damage are great, but well defined
examples of proved harm are few, perhaps
because biological accumulation is not as
generally damaging as feared, but also
perhaps because the ecological relation
ships involved are so extremely complex
that they are difficult to unravel.
Light has been cast on this phenomenon
by numerous researchers. Cope (1965),
investigating the distribution of DDT
through various compartments of a simpli.
fled ecosystem, reported that two weeks
after the application of 14 C—DDT at a con-
centration of 20 tg/l to aquarium water,
the water contained 0.4 2 iig,/l, soil con-
tained 6 pg/kg, and vegetation contained
15,600 pg/kg. Two weeks after fish were
placed into the aquaria, they contained
1,000 pg/kg of DDT. Woodwell et aL
(1967) investigated biological concentra-
tion of DDT among various trophic levels
of a Long Island salt marsh and reported
values increasing from 0.04 mg/kg in
plankton to 75 mg/kg in ring.billed gulls.
Highest concentrations occurred in scaveng-
ing and carnivorous fish and birds, al-
though the birds had 10—100 times more
than the fish. Gakstatter and Weiss (1967)
exposed bluegills and goldfish in aquaria
to ‘ 4 C—DDT, dieldrin, and lindane to study
uptake, retention, and release by the fish.
They showed that the lindane was entirely
released within two days and that more
than 90% of the initial dicldrin was elimi-
nated within two weeks. However, more
than 50% of the DDT was still retained
after 32 days. More significant, they
showed that DDT and dieldrin were
readily transferred from contaminated to
uncontaminated fish held in clean water.
Apparently, some of the persistent insecti-
cides are capable not only of undergoing
biological magnification but also of cycling
between water and the organisms living
in it.
The accumulation of pesticides in the
bodies of fish has been cited as the proba-
ble cause of the secondary poisoning of a
variety of fish-eating birds. The most nota-
ble example is that described by Hunt and
Bischofl (1960) in which western grebes
overwintering on Clear Lake, California
died, presumably from eating fish contain-
ing high DDD residues. Keith (1966) re-
ported an unusually high mortality of fish-
eating birds between 1960 and 1962 at the
Tule Lake I ational Wildlife Refuge in
California, which he attributed, circum-
stantially, to ingestion of toxaphene ac-
cumulated in fish. A study of this refuge
in 1965—66 (Godsil and Johnson, 1968),
when endrin was the principal insecticide
used on the nearby irrigated farmland,
indicated a marked increase of endrin in
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130
all trophic levels during the crop-growing
season (May-Sept.) with a subsequent de-
cline to near or below detectable limits in
the off season. Fish accumulated maxima
of 97 pg/kg in 1965 and 107 &g/kg in
1966. Endrin was not established as a
permanent residue, and no wildlife losses
were recorded. It is apparent that the so-
called “hard” insecticides are not equally
accumulative or persistent in food chain
compartments.
Butler (1966 a, b, c) has done exten-
sive work on the effects of low levels of
chlorinated hydrocarbon insecticides on or-
ganisms of the marine environment. He
showed that DDT in the water at levels
as low as 1 &g/l caused a 20% reduction
in oyster growth, and that oysters are
efficient concentrators of DDT in t’heir
tissues. He believes that pesticides may be
the cause of ill-defined but significant
mortality, loss of production, and perhaps
changes in the direction of natural selec-
tion in estuarine fauna. Cope (1965) con.
cluded that exposure to sublethal amounts
of DDT increases fish mortality by reduc-
ing resistance to other stresses.
Burdick and his co-workers (1964)
in New York demonstrated that lethal
amounts of DDT can be transmitted from
female lake trout to their offspring through
the egg. Lethality bore no relation to the
concentration of DDT in the female. Fry
died when the final contents of the yolk
sacs were absorbed. These deaths occurred
when the eggs contained DDT equivalent
to 2.9 mg/kg or more of fry. This situa-
tion came to light when complete loss of
lake trout fry occurred in 1955 and 1956
at a Lake George fish hatchery. It is a
most subtle adverse effect that would be
detected only under hatchery or laboratory
conditions.
The influence upon the survival of
aquatic organisms of transovarially con-
veyed pesticide residues is a subject
worthy of further research. The period of
dependence upon food stored in the egg
sac may be for numerous fish species the
most vulnerable period in their life his-
tories as far as pesticides are concerned.
If this is true, the chances are very slight
that population losses would be directly
observed in nature short of virtual elimina-
tion of a major species.
Much has been written about the effects
of long-term exposure of aquatic organisms
to pesticides at sublethal levels, but we still
have a remarkably small amount of com-
pellingly positive information indicating
danger from organic chlorinated insecti-
cides. DDT has received by far the most
attention, possibly because its residues are
so universally distributed. We need more
research on other persistent insecticides.
Although we do not have agreement within
the scientific community concerning the
danger of persistent residues in living or-
ganisms and in the environment, perhaps
all can agree that it would be better if we
did not have these uncontrolled residues.
Other Water Uses
In April 1968 the National Technical
Advisory Committee on Water Quality
Criteria of the Federal Water Pollution
Control Administration submitted its first
report to the Secretary of the Interior
(Anon., 1968). This volume constitutes
the most comprehensive document to date
on water quality requirements for various
uses. It contains recommendations for per-
missible limits for some pesticides.
The Subcommittee on Public Water
Supplies based its recommendations on
pesticides upon recommendations sub-
mitted by the Public Health Service Ad-
visory Committee on Use of the Public
Health Service Drinking Water Standards.
The values were derived for that com-
mittee by an expert group of toxicologists
and were established at those levels which,
if ingested over extensive periods, could
not cause harmful or adverse physiological
changes in man. In the case of aldrin,
heptachlor, chlordane, and parathion the
values were set even lower than those
physiologically safe, to avoid levels that
could be tasted or smelled. Table 1 con-
tains these recommendations.
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Table 1. Surface Water Criteria for Pesticides
in Public Water supplies (mg/i)?
Permissible
criteria
Desirable
criteria
Aidrin
0.017
Absent
Chiordane
0.003
‘
DDT
0.04
“
Dieldrin
0.017
‘
Endrin
0.001
“
Heptachlor
0.018
“
Heptachlor epoxide
0.018
“
Lindane
0.056
“
Methoxychior
0.035
“
Organic phosphates
plus carbamates
0.12
“
Toxaphene
0.005
“
2,4.—D plus 2,4,5—T,
plus Z,4,5—TP
0.1
“
‘Adapted from Water Quality Criteria, Report
of the National Technical Advisory Committe to
the Secretary of the Interior, April 1968. Wash-
ington, D. C.
2 As parathion in cholinei,terase inhibition. It
may be necessary to resort to even lower con-
centrations for some compounds or mixtures.
The subcommittees concerned with
criteria for aquatic and wildlife (both
freshwater and marine) and for agricul-
ture each considered pesticides. The
criteria, or formulae for determining
criteria values, are generally too complex
to justify discussion here, and the reader
is referred to the original source.
An alternative suggestion for a water-
quality criterion for fish, based on a group
effect of about 100 organophosphorus and
carbamate compounds, was derived at the
Southeast Water Laboratory (Nicholson,
1967). This practical suggestion was based
upon the ability of these compounds to
inhibit acetyl-cholinesterase activity in the
brains of fish. The degree of inhibition is’
a function of the compound, its concentra-
tion in water, and the duration of ex-
posure. Death results from inhibition rang-
ing from 40 to 70%. As little as 10%
inhibition can be measured and statistically
confirmed in a group of ten fish of the
same species and of similar size. Therefore,
it was suggested that 10% acetylcholines-
terase inhibition in fish brain would serve
as a good criterion of water quality in-
volving chemicals capable of causing this
inhibition. Unfortunately, no group effect
for organochlorine insecticides has yet
been developed upon which a similar
criterion can be established.
Pesticide Pollution Control
The Southeast Water Laboratory has
national responsibility within the Federal
Water Pollution Control Administration
for research leading to the control of pesti-
cide pollution. Control is generally easiest
at point sources; i.e., at industrial sources
where waste effluent is discharged to a
stream at a single outfall. We are cur-
rently beginning an inventory of waste-
treatment practices at pesticide manufac-
turing and pesticide using industrial plants
to establish a mutually beneficial relation-
ship with some of these industries. Control
may be accomplished by a variety of waste-
treatment processes and by in-plant process
changes. Effective control may be as simple
as the provision of facilities for biochemi-
cal oxidation of effluents with auxiliary
provision of a basin for containing ex-
traordinary peak loads of wastes for more
leisurely disposal. Our Laboratory is
equipped with a variety of advanced
analytical instruments, including a 100-
megacycle high-resolution nuclear mag-
netic resonance spectrometer and a com-
puterized mass spectrometer, with which
we are able to determine the chemical
nature of industrial waste effluents and
assist in optimizing the design of advanced
waste treatment systems. -
The control of pesticide pollution as-
sociated with rural runoff is much more
difficult to accomplish because its entrance
into watercourses is not localized. There-
fore, control must be accomplished by
other means and ultimately rests in the
hands of the users. Land-management
practices designed to retard water runoff
and soil erosion certainly are helpful meas-
ures. The retention of an untreated buffer
strip adjacent to mountain streams was
shown to prevent the runoff of DDT ap-
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132
plied for forest insect control (Grzenda
et at., 1964).
We are conducting research with pure
clay mineral model soils to develop basic
concepts relative to the retention of rep.
resentative pesticides on the land or their
failure to be retained. Recently our sci-
entists, cooperating with associates at
Purdue University, demonstrated that
s-triazine herbicides may be irreversibly
adsorbed onto montmorillonite clay, and
in so doing, undergo a chemical change
to an innocuous compound (Russell et at.,
1968). Basic concepts developed are later
confirmed with natural soils. The results
frequently are directly applicable to rural
runoff control recommendations.
Pesticide runoff from the land is directly
related to runoff losses of both water and
surface soil; the/I serve to transport
pesticides from farm or forest to water.
courses. Controlling this process are cli-
matic, edaphic, hydrologic, physiographic,
and cultural factors. If we knew more
about the interplay of soil type, slope of
the land, rainfall, and other climatic fac-
tors, cropping practices, and the behavior
of the pesticides in use, we should be able
to recommend measures to reduce the im-
portance of rural runoff as a source of
water pollution by pesticides. These rec-
ommendations might simply concern which
pesticides to use or not to use in a given
combination of circumstances.. It might
develop into water-pollution-control rec-
ommendations for geographic zones.
A comparable development has already
been made in agriculture. I refer to the
universal soil-loss equation that is appli-
cable to. guiding conservation farm plan-
fling throughout the United States (Wisch-’
meier et al, 1958; Wischmeier, 1969;
Wischmeier and Smith, 1960, 1965). The
factors upon which this equation is based
are rainfall, soil-erodibility, slope length
and gradient, cropping management, and
erosion control practices. The possibility
of extending the universal soil-loss equa-
tion and applying it to the prediction and
control of pesticide pollution associated
with rural runoff seems good and is being
explored.
In the meantime, socio-economic devel-
opments are occurring outside the field of
water pollution control that tend toward
reduction of the water pollutional impact of
the persistent organochlorine insecticides.
The development of resistance to insecti-
cides among cotton, corn, and sugarcane
pests, to name a few, has forced total or
partial abandonment of the formerly pre-
ferred “hard” insecticides in favor of more
effective and, incidentally, less persistent
types. Food and Drug Administration-con-
trolled tolerance levels have required other
changes. There is a growing public inter-
est in environmental contamination control
that may bring forth legislation outlawing
the use of the “hard” insecticides as
“hard” detergents were outlawed a few
years ago. I should not like to see this
happen, but would prefer to see sub-
stitutes used whenever it is feasible to do
so, retaining the troublesome insecticides
for use where they are absolutely neces-
sary and where their usage will not result
in further environmental contamination.
It is the responsibility of entomologists
and leaders in the field of pesticide usage
to take note, to look beyond the im-
mediate problem of controlling insects,
•and to assume greater responsibility for
preventing undesirable side effects result-
ing from the use of pesticides.
References Cited
Anonymous. 1961. A report on fish kills occurring
on Choccolocco Creek and the Coosa River
during May 1961. Rep. of Ala. Water Improve-
ment Commission. Montgomery. Ala.
Anonymous 1963. Use of pesticides. President’s
Science Advisory Committee Report. Gov’t.
Printing Office, Washington. D. C.
Anonymous. 1964. Report of Peace River para-
thion incident, Dcc. 23, 1964. Fla. State Board
of Health, Bur. San. Eng., Jacksonville, Fla.
Anonymous. 1968. Water Quality Criteria, Re-
port of the National Technical Advisory Com-
mittee to the Secretary of the Interior. Gov’t.
Printing Office, Washington, D. C.
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Bailey, T. E., and J. R. Hannum. 1967. Distribu-
Lion of pesticides in California. J. San. Eng.
Div., Proc. Amer. Soc. Civil Eng. 93(SA5):
27.43.
Burdick, C. E., E. .1. Harris, II. 1. Dean, J. M.
Walker, J. Skea, and D. Colby. 1964. The
accumulation of DDT in lake trout and the
effect on reproduction. Trans. Amer. Fisheries
Soc. 93(2): 127.136.
Butler, P. A. 1966a. Fixation of DDT in estu-
aries. Trans. 31st N. Amer. Wildlife and Natural
Resources Conf. PubI by Wildlife Management
Institute, Washington, D. C.
1966b. The problem of pesticides in
estuaries. Amer. Fisheries Soc, Special Pub. 3,
pp. 110.115.
1966c. Pesticides in the marine environ-
ment. J. AppI. Ecol. 3 (Suppl.), pp. 253-259.
Cope, 0. B. 1965. Research in Pesticides. Aca-
demic Press, N. Y., p. 115.
Cottam, C. 1960. Pesticides and waler pollution.
Proc. Nat. Conf on Water Pollution, Dep.
HEW, Washington, D. C., pp. 222-235.
Eye, J. D. 1968. Aqueous transport of dteldrin
residues in soils. J. Water Poll. Cont. Fed,
Res. Suppl. 40(8): R316.R332.
Gakatatter, J. H., and C. M. Weiss. 1967. The
elimination of DDT_.C14, dieldrin—C’ 4 , and
lindane—C’ from fish following a single sub-
lethal exposure in aquaria. Trans. Amer. Fish-
eries Soc. 96(3): 301-307.
George, J. L. 1959. Effects on fish and wildlife
of chemical treatments of large areas. J. For-
estry 57(4): 250-254.
Godsil, P. J., and W. C. Johnson. 1968 Pesticide
monitoring of the aquatic biota at the Tule
Lake National Wildlife Refuge. Pesticide Moni-
toring J. 1(4): 21-26.
Grzenda, A. R., H. P. Nicholson, J. I. Teasley,
and J. H. Patric 1964. DDT residues in
mountain stream water as influenced by treat-
ment practices. J. Econ. Entomol. ‘57(S): 615-
618.
Hoffman, C. H., and A. T. Drooz 1953. Effects
of a C—47 airplane application of DDT on
fish-food organisms in two Pennsylvania water-
sheds. Amer. Midland Natur. 50(1) : 172-188.
Hunt, E. C., and A. I. Bischoff. 1960. Inimical
effects on wildlife of periodic DDD application
to Clear Lake. Calif. Game and Fish 46(1):
91-106.
Keith, 1. 0. 1966. Insecticide contaminations in
wetland habitats and their effects on fish-eating
birds. J. AppI. Ecology 3 (Suppl.): 71-85.
Nicholson, H. P. 1967. Pesticide pollution con-
trol. Science 158(3803): 871-876.
Nicholson, H. P., A. R. Grzenda, and J 1. Teas-
ley. 1966. Water pollution by insecticides: A
six and one-half year study of a watershed.
Proc. Symp. on Agr. Waste Waters. Water
Resources Center, Univ. of Calif., Davis, Rep.
10, pp. 132-141.
Russell, J. D, M. Cruz, J. L. White, C. W.
Bailey, W. R. Payne, Jr., J. D. Pope, Jr., and
J I. Teasley. 1968. Mode of chemical degrada-
tion of s-triarines by montmorillonite. Science
160: 1340-1342.
Weaver, L., C. C. Cunnerson, A. W. Breiden-
bach, and J. J. Lichtenberg. 1965. Chlorinated
hydrocarbon pesticides in major U. S. river
basins. Pub. Health Reps. 80(6): 481493.
Wischmeier, W H. A rainfall erosion index for
a universal soil-loss equation. 1959. Soil ScL
Soc. Amer. Proc. 23(3): 246-249.
Wischmeier, W. H., and D. D Smith. 1960. A
universal soil-loss equation to guide conserva-
lion soil planning. 7th Intern. Congress of
Soil Sci., Madison, Wis, pp 418-425.
Wischmeier, W. H., and D. D. Smith. 1965. Pre-
dicting rainfall-erosion losses from cropland
east of the Rocky Mountains: Guide for selec-
lion of practices for soil and waler conserva-
tion. U. S. Dept. Agr., Agr. Handbook 282
Wischineier, W. H., U. D. Smith, and R. E.
Uhland. 1958. Evaluation of factors in the soil-
loss equation. Agric. Eng. 39(8); 458-462.
Woodwell, C. M, C. F. Wurster, Jr., and P. A.
Isaacson. 1967 DDT residues in an East Coast
estuary: A case of biological concentration of
a persistent insecticide. Science 156(3776)
821-824.
Young, L. A, and H. P. Nicholson. 1951. Stream
pollution resulting from the use of organic
insecticides. Progr. F.sh-Culiuiist 13: 193-198.
VOL. 59, Nos. 4.5, APRIL-MAY, 1969

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PESTICIDE PROBLEMS.. IN WATER HYGIENE AND
THEIR CORRECTION
Frederick C. Kopfler
A. GUIDELINES FOR PESTICIDES IN DRINKING WATER
The Water Supply Programs Division of the Office of Water Programs is responsible for
recotmnendipg standards, limits and guidelines for a wide variety of chemical and bio-
logical contaminants of drinking water. Pesticides are among the chemicals for which
limits have been recommended. The list of pesticides and the respective concentra-
tion limits of each are shown in Table I. These guidelines were formulated on the
basis of fish toxicity data that were available. New standards have been proposed
and are under consideration at this time. The proposed standards include additional
compounds and list maximum allowable concentrations for both short term and chronic
exposure. The proposed allowable concentrations for chronic exposure are generally
higher than those of the present guidelines, but they are derived from animal and
human toxicity data.
TABLE I
RECOMMENDED LIMITS FOR PESTICIDES IN DRINKING WATER
PESTICIDE MAXIMUM PERMISSIBLE
CONCENTRATION, mg/LITERa
Endrin 0.001
Aldrin 0.017
Dieldrin 0.017
Lindane 0.056
Toxaphene 0.005
Heptachlor 0.018
Heptachlor epoxide 0.018
DDT 0.042
Chlordane 0.003
Methoxychlor 0.035
Total organophorsphorous and
carbamate compoundsb 0.1
2,4,STP Individual limits = 0.1 mg/liter; Sum of
2,4,5T any combination of chlorinated phenoxy
2,4D aklyl pesticides = 0.1 mg/liter
aFor long term exposure.
b xpressecj in terms of parathion equivalent cholinesterase inhibition.
cShort period limit only: 2 to 3 days, no more than once or twice a year.
The thirteenth edition of Standard Methods for the Examination of Water and Wastewater
includes a tentative gas chromatographic method for the determination of chlorinated
hydrocarbon pesticides. Methods for the determination of organophosphorous and

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Very little, if any, information is available concerning the quality of the water
consumed by individuals and families not served by public or community water sources.
A systematic survey of individual water supplies was conducted in four widely sepa-
rated counties in Georgia. One of the objectives of the project was to examine a
representative number of types o these supplies for pesticides as in the community
water supply study. The 78 samples that were taken represented dug wells, bored,
jetted, and driven wells, springs and cisterns. Table III summarizes this data. Two
interesting comparisons between this data and that of the community supplies is that
DDT was detected in more than 60% of these supplies as compared to 46.4% of the com-
munity supplies. While only 3.5% of the community supplies contained a residue at a
concentration 5 0.1 ppb the figure for the individual supplies is 9%.
TABLE III
FREQUENCY OF OCCURRENCE OF INDIVIDUAL PESTICIDES IN
INDIVIDUAL WATER SUPPLY STUDY
NO. OF TINES % SAMPLES MAXIMUM NO. OF SAMPLES
PESTICIDES DETECTED POSITIVE VALUE ppb > 0.1 ppb
pp’DDT 48 61.5 0.5 0.2, 0.3, 0.5
Die ldrln 5 6.4 <0.1
Endrin 4 5.1 0.2 1 @ 0.2
Lindane 2 2.6 0.9 1 @ 0.9
Chiordane 2 2.6 <0.1
Heptechlor 2 2.6 0.2 1 @ 0.2
Hep tachlor—
epoxide 1 1.3 0.2 1 @ 0.2
Aidrin 0 0 — —
Table IV is a comparison of the distributi,on of pesticides in the community water
supplies and the distribution in the individual supplies. It can be seen that about
10% fewer of the individual supplies were free of detectable residues. In the corn-
munity water supplies, pp’—DDT was the residue that accounted forrn 80% of those sam-
ples containing one pesticide; the comparable value was 52% for the individual
supplies.
TABLE IV
DISTRIBUTION OF RESIDUES IN TUE WATER SUPPLY STUDIES
NUMBER RESIDUES COMMUNITY WATER INDIVIDUAL WATER
DETECTED SUPPLY STUDY SUPPLY STUDY
Number Number
0 72 42.4 25 32.0
1 56 32.9 46 59.0
2 18 10.6 4 5.1
3 13 7.6 2 2.5
4 8 4.7 1 1.3
5&6 3 1.8 0 0

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carbatnate compounds are currently being evaluated. Methods for the determination of
the herbicides are available and should be evaluated before the fourteenth edition of
Standards M thods is published.
B. SURVEYS OF PESTICIDES IN DRINKING WATERS
In 1969, the Bureau of Water Hygiene of the U. S. Public Health Service conducted a
Community Water Supply Study (CWSS) to determine if the American consumer’s drinking
water met the Drinking Water Standards. This study was designed to give an assess-
ment of drinking water quality, water supply systems and surveillance programs in
urban and suburban areas in each of the nine regions of the Department of Health,
Education, and Welfare. These areas were selected to give examples of the several
types of water supplies in the country.
A whole Standard Metropolitan Statistical Area (SMSA) was the basis of each study,
except in Region I where the entire State of Vermont was included, with evaluations
made on all public water supply systems in each study area. This coverage allowed an
assessment of the drinking water quality of the large central city, the suburbs, and
the smaller communities located in the counties in the SMSA, and the interaction
between them.
Table II summarizes the pesticide data obtained from the analysis of 170 samples
during the CWSS.
TABLE It
FREQUENCY OF OCCURRENCE OF INDIVIDUAL PESTICIDES IN CWSS
NO. OF TIMES % SAMPLES MAXIMUM NO. OF SP 1 MPLES
PESTICIDES DETECTED POSITIVE VALUE ppb > 0.1 ppb
pp’DDT 79 46.4 <0.1 0
Endrin 26 15.3 <0.1 0
Dieldrin 17 10.0 0.1 1 @ 0.1
Lindane 16 9.4 0.2 2 @ 02
Chiordane 13 7.6 0.2 1 @ 0.2
Heptachlor 11 6.5 0.2 2 @ 0.2
Heptachlor—
epoxide 10 5.9 <0.1 0
Aldrin 7 4.1 <0.1 0
Only six samples or 3.5% of the total contained a residue at a concentration equal
to or exceeding the reporting limit of 0.1 ppb. DDT was detected in almost 50% of
the supplies. Aldrin was found in 7 supplies. It was determined that six of these
were ground waters while one was a surface supply and it also contained four other
residues. Toxaphene and methoxychlor were not detected.
A similar evaluation of water supplies was conducted in Tennessee in late summer of
1970. Twenty—six samples were analyzed for chlorinated pesticides; one contained
0.1 ppb chlordane, two contaIned <0.1 ppb pp’—DDT and the no residues were detected
in the remaining 23.

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In addition to these special studies, the Division is responsible for the on going
surveillance of Interstate Carrier Water Supplies. There are 710 such water supplies
and each must be examined at least once every three years. Only trace amounts of
chlorinated pesticides have been detected in samples submitted for analysis in con-
junction with this program.
The growing national attention to the use of 2,4,5—T has brought up the question as
to whether this herbicide is getting into drinking water supplies where it may con-
stitute a potential hazard to those who consume the water. There is very little
information available at the present time to provide a basis for answering this ques-
tion because monitoring of public water supplies in the United States for 2,4,5—T and
related herbicides has been limited. It is generally recognized, however, that the
contamination of drinking water supplies represents a potentially significant route
for exposure of human beings to this material especially in those areas of the country
where there is direct application of th? herbicide to water for weed control and to a
lesser extent whete there is runoff from forested areas treated for brush control.
In the evaluation of public drinking water supplies the present maximum permissible
concentration is 0.1 mg/liter (ppm) for either 2,4,5—T or the sum of any combination
of 2,4,5—T and other related compounds as was shown in Table I. A survey was planned
so that the results could be assessed in relation to this guideline in the future
consideration of an ultimate standard for 2,4,5—T and other related herbicide in
drinking water.
This survey was conducted during August through November 1970. Table V is a su nary
of the results of this survey.
TABLE V
OCCURRENCE OF PHEN0X ACID HERBICIDES IN 58 WATER SUPPLIES
WATER SUPPLIES IN
HERBICIDE WHICH HERBICIDE DETECTED CONCENTRATION (ppb)
Number Percent Low Medium High
2,4,5—T 11 19.0 <0.5 <0.5 0.57
2,4—D 18 31.0 <0.5 <0.5 3.44
2,4,5—TP 4 6.9 <0.5 <0.5 <0.5
Analyses of the data obtained from this one—time sampling of community water supplies,
which followed generally the period of seasonal use of 2,4,5—T and related herbicides,
indicate that only traces of these herbicides could be detected in up to 19 to 31
percent of the water supplies. These trace amounts of 2,4,5—T and related herbicides,
generally at concentrations less than 0.5 ppb and ranging up to 0.57 ppb for 2,4,5—T
and 3.44 ppb for 2,4—D in the raw and/or finished waters, are extremely low when
compared to the present Public Health Service guideline of a maximum permissible con-
centration of 0.1 mg/liter (ppm) for either the individual herbicide or the sum of
any combination of these herbicides.
On the other hand, the survey substantiated the unquestionable fact that the use of

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2,4,5—T and related herbicides on watershed areas and water supply sources results in
the occurrence of the herbicides in the raw and/or finished waters of community water
supplies. The lack of occurrence or the detection of 2,4,5—T and related herbicides
at very low concentrations or in trace amounts in community water supplies in this
survey could possibly be the source of a false sense of security from the public
health standpoint.
The results of these surveys of drinking waters indicate that contamination of a
water supply with a chlorinated pesticide in excess of values in Table I would be an
exception rather than the rule. However, the water systems in many metropolitan areas
are presently faced with several problems relative to the use of pesticides, insecti-
cides, and herbicides. This includes their use by homeowners on lawns and around the
foundation of their homes to control termites, by the farmers for agricultural con-
trol, and by utilities, highway departments, and local governments for controlling
growth along right of ways.
C. INVESTIGATION OF A PRIVATE WELL
The use of pesticides and insecticides on lawns and for termite control is a concern
of public health officials. All the substances tested during the CWSS have been and
are being used for termite control. They are the so called hard pesticides, such as
chlordane, dieldrin, endrin, aldrin, toxaphene heptachlor, lindane, and DDT, which
remain in the soil for six months to as much as seven years. In providing protection
for a house, the exterminator jets a solution about eight feet into the ground all
around the foundation and in the basement floor. The number of injections and
amount of substance depends upon the size, shape, and other characteristics of the
house. In the past chiordane was most widely used; however, dieldrin now seems to be
more effective and to last longer. Registration of a ldrin, dieldrin and mirex for
all uses were cancelled last year but they may still be in use.
The soft substances which breakdowd faster require more frequent reapplications than
the hard. It is quite apparent that further study is necessary to determine which
procedure should be used, hard agents with less frequent application or soft with
more frequent applications, to insure that the potential hazard o public and private
wells is eliminated.
During the Community Water Supply Study, the Suffolk County, New York Department of
Health staff investigated a private well supplying a house that had recently been
treated for termites. A solution was used containing approximately 10,000 ppm of
chlordane. It had been injected into the ground around the foundation and through
the cellar floor. It was also sprayed on the wood just above the foundation. Based
upon a noticeable change in the taste of the water, the county requested that the
Bureau of Water Hygiene run the series of pesticide tests that were being performed
for the CWSS.
Of the ten pesticides for which the sample was tested, three were found in trace
amounts similar to that found in public supplies: dieldrin, <0.1; heptachlor, 0.2;
and heptachlor—epoxide, 0.1 ppb. However, 12.9 ppb of chiordane were found. This
is over four times the limit of 3 ppb. The owner of the contaminated private well,
at the request of the county staff, pumped his well fairly constantly over a five to
six week period. A second sample was taken and also forwarded to the Gulf Coast
Water Hygiene Laboratory for analysis. The tests on this sample showed 1.5 ppb of
chlordane with none of the other substances being detected.

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Although there was an old uncapped well nearby which m ht have been partially respon-
sible, the fact that the well was only three feet from the house foundation would
seem to indicate a problem regardless of the old well. Many of the older houses in
that county have their wells close to house foundations or in the basement. Presently
the county sanitary codes require only a three foot space between the house foundation
and its well. In view of these facts, it is hard to imagine such wells as not be—
coining contaminated.
The foregoing, although based on a private well case, clearly indicates need in
several areas. A complete investigation should be made as to the entrance of pesti-
cides into ground water, their persistance, and their rate and distance of travel.
Such information Is needed to insure the future protection of public water supply
ground water sources.
D. PROBLEMS TO SOLVE
In the past, all the pesticides for which an examination was made during the water
supply studies were used on crops. However, over the past five years they have grad-
ually been replaced with new ones. There are too many to enumerate here; however, as
an example, a partial list of pesticides recommended in 1970 for potato crop control
for the State of New York are listed below.
Blight Control
Seed Treatment Weed Control Insect Control
Per Merge Dithane
Cap tan linuron parathion Manzate
Polyram Patoran endosulfan (Thiodan) polyram
Dithane Eptam carbaryl (Sevin) Daconil
amitrole Difolatan
Many herbicides in addition to 2,4,5—T, 2,4—D and 2,4,5—TP are used for weed control
along highways, railroads, power transmission lines, etc. Following is a list of
such compounds that have been used in watersheds that serve as water supplies:
Aquathol Plus (disodium 3,6—endoxohexahydrophthalate), Radapon and Dalpon (2,2—
dichioro propionic acid), Tordon (4—amino—3,4,5—trichloro picolinic acid), SIinazine
80W (2—chloro—4 ,6—bis—(ethylamino)—s—triazine), Bromacil (50—bromo—3—seo—butyl—6—
methyluracil).
Expanding the foregoing lists to a nationwide basis, the necessity for constant
research relative to the possibility of such chemicals getting into water supplies,
surface and ground, Is obvious. Such questions as does the chemical persist while
being carried through the soil to the wells or over the gound to the reservoir, how
far away from drinking water source should the chemical be applied, and most impor-
tant is the chemical a health hazard when consumed by man through water must be
answered.
Another important consideration that metropolitan health officials must consider is
the use of irrigation wells as water supply sources as farms disappear and suburbia
takes over.
The only drinking water standard that exists to protect the consumer from harmful
organic chemicals other than phenols, detergents and those pesticides listed in
Table I is the carbon—chloroform extract. Two hundred micrograms of these ill—
defined substances per liter of drinking water are allowed. It has been estimated
that activated carbon may remove only 10% of the organic matter from water, and
chloroform extraction of the carbon does not remove all that is adsorbed. Thus the
level of exposure of the public to organics via drinking water is not accurately
known. Therefore, probably the greatest problem facing chemists in the field of
water hygiene today is the Identification o organic compounds, including pesticides,
found in drinking water so that proper standards can be set.

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FATE OF PESTICIDES IN SOILS AND CROPS.
B. J. Stojanovic, Fay Hutto, and W. W. Walker
By definition pesticides are substances or mixtures of substances that may be
used to destroy or otherwise control any unwanted form of plant or animal life.
The ending —dDE of the term pesticide means killer. In this regard pesticidal
materials are purposely applied to the soil and/or crops to control a wide
spectrum of pests such as insects, rodents, plant pathogens, weeds, and others.
Interestingly, control of pests is not a 20th century invention but rather it
has been practiced in some rudimentary form from the very beginning of man’s
existence on the earth or at least as far back as man began recording his
history. For example, in the year 1000 B.C. the author of the Iliad and Odyssey,
the Greek poet Homer, wrote of sulfur.as having “divine and purifying fumigation”
properties which can ward off pests. 1 The use of arsenic, which had been as-
signed similar properties, was suggested by the Roman author Pliny.’ These
chemicals are still in use today either as such or as components of various
pesticidal chemicals.
Currently pesticides are used so extensively that the prosperity of Homo sapiens
is attributed largely to their effects upon his competitors, the pests. However,
contrary to the general agreement that pesticides are necessary for protection
of our health and comfort and of our food and fiber supplies, the widespread use
of synthetic organic compounds has introduced an unprecedented array of chemicals
into the environment. At the same time it has become increasingly more evident
that some pesticides have serious short comings, the most widely acclaimed of
which are toxicity to non-target organisms and long persistence in the environ-
ment. The ability of certain pesticides to appear far from the site of their
application and the property to persist and accumulate in soils, crops, and
animal tissues (i.e. the movement of pesticide residues into the food chains)
give cause for alarm whenever it becomes known that their rate of accumulation
in the biota surpasses their rate of breakdown and detoxification. In fact,
persistence and toxicity towards non—target organisms determine whether or not
a pesticide is desirable, and in due time may be the main basis for a decision
about its further usage or discontinuance.
As pesticides in recent years have become man’s most relied-upon weapon in his
arsenal of weapons in the struggle to control or eradicate pests, the necessary
technologies have been developed to serve the needs of agriculture and public
health. Obtaining information on the fate of these chemicals in soils and crops,
however, has not kept pace with these developments. Clearly, in the past the
criteria for selection of effective pesticides has been based on toxicological,
economic, and selectivity factors. The reasons were: (1) most agricultural
products brought very narrow margins of profit; (2) manufacture and usage of
pesticides had to guarantee suitable returns for the investments made; and (3)
the pesticide had to control or destroy the target pests. Present emphasis on
a pollutant—free environment necessitates critical studies and as thorough an
understanding as possible of the fate of various pesticides that tend to be
stored in soils and crops. Moreover, as agriculture becomes increasingly
dependent on chemistry, the importance of the fate of chemicals in soils and
crops will be magnified still more.

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This brief review attempts to present a generalized or oversimplified version
of certain processes directly or indirectly affecting the fate of pesticides
in soils and crops. The effect of soil microorganisms on the fate of pesticides
will be emphasized. The reader Is advised to consult several excellent reviews
on specific topics related to the subject of this review, some of which are
referred to In this review.
EFFECT OF PIIYSICOCHEMICAL PROCESSES ON THE FATE OF PESTICIDES
Soils repreeent complex natural systems within which numerous physicocheniical
and biological processes operate. They are dynamic bodies, consisting of
mineral and organic matter, water, and air combined in three phases: solid,
liquid, and gaseous. Many different kinds of soils exist throughout the world.
Differences from location to location generally reflect changes in topography,
drainage, parent material, or some other factor. When soils contain the proper
amounts of air and water, they supply mechanical support and, In part, nutrients
for crops.
The fate of pesticides applied to crops and soils has been studied for about
25 years. The amount of work has increased exponentially during that time with
a very large increase during the past four or five years.
Pesticidal chemicals that are added to the soil may be inactivated, destroyed,
or removed from the soil by several processes. The end result of these processes
is the detoxification or cleansing of the ecosystem. Such cleansing of the
environment involves both physicochemical and biological mechanisms. The physico-
chemical detoxification may result from: (1) adsorption; (2) movement; (3)
photodecomposition, and (1 ) chemical riaction.
Adsorption of pesticides on soil particles is one of the more important of the
deactivating mechanisms because it influences all others. 2 Adsorption is attri-
buted to physical forces (van der Waals), hydrogen bonding, coordination complexes,
and chemical forces (coulonibic). 3 The extent of adsorption is related to the
chemical nature of the pesticide, soil moisture, p1 1, temperature, type of
formulation and individual colloid. In general prediction of pesticide adsorp-
tion, especially by the silicate surfaces, is largely empirical. The adsorption
of most pesticides could be best estimated from the soil orqanlc matter content,
with pH and clay content sometimes being relevant. 3 As a rule of thumb adsorp-
tion decreases with increasing pH and temperature, and it is higher in organic
than in mineral soils and in heavy textured than In light textured soils.
Exceptions, however, are not uncommon. An extensive adsorptipn does not neces-
sarily mean a tight holding of pesticides to the surfaces of the colloids. Thus,
there may be an insignificant loss of activity despite the removal of a substantial
amount of the toxic chemical from the soil solution.
Movement is understood as the physical transport of pesticides within and through
the soil. The processes are volatilization, leaching, and runoff. Volatilization
frequently is the chief avenue by which certain fumigants and a variety of
insecticides and herbicides are removed from the soil. Volatilization is de-
pendent on the vapor pressure of pesticides and soil texture, moisture,
adsorptivity, temperature, and pH. Based on the existing information It could
be generalized that volatilization of pesticides increases with increased
temperature and lower clay or organic matter content, and is greater from moist
than from dry soils, but becomes negligible as pores become water-saturated. 3
Leaching or the movement of solutes In the liquid phase consists of molecular
diffusion and mass transfer. The rate and magnitude of leaching is associated
with the amount of water passing through a layer of,sOIl, be it from rainfall
or from irrigation. The leaching, or movement by gravity, is dependent upon
the physical and chemical characteristics of the soil, the nature of the formu-

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lation of the chemical, and the amount of water migrating through the profile.
Leaching, runoff, and soil erosion can be the forerunners to pollution of
ground water, streams, or rivers. Runoff is the lateral movement of pesticides
across the soil surface. Factors enhancing runoff are steep topography, low
soil permeability, and intense and/or prolonged precipitation. Since most
pesticide runoff is short range on cultivated fields, stream contamination by
pesticides in the runoff appears to be unlikely unless it is tied up with exten-
sive soil erosion.
Photodecomposition is the breakdown of pesticidal molecules under the influence
of light. Conceivably photodecomposition can occur only on the surface of the
soil; therefore, only those compounds applied to the surface or those which have
moved to the surface during drying will be degraded. Most research deals with
reactions occurring in solution, often organic rather than aqueous. At present
photolysis is not well understood, and future endeavors should be centered on
establishment of the quantitative significance of photodegradation at the soil
surface.
Chemical reactions of pesticides in soil display similarities to those in the
test tube. They involve the attack of a reagent on a reactive compound. Because
of its structure soil presents an effective medium for the conduct of such reac-
tions because it permits th confluence of oxygen, water surfaces, and pesticides
with the soil constituents.” Chemical reactions of pesticides may take place
independently of soil or they may be soil—catalyzed. Most of these reactions
can be classified as either catalytic or hydrolytic. The consensus of opinion
among scientists appears to be that the degradation of pesticides in soils by
chemical reaction may be a more common process than was previously realized.
EFFECT OF BIOLOGICAL PROCESSES ON THE FATE OF PESTICIDES
The biological processes involved in the detoxification of pesticides in soils
and crops involve the activities of soil microorganisms and the uptake and
metabolism of pesticides by plants.
Microbial metabolism represents a main channel of degradation and detoxification
for many pesticides. Microorganisms are often the sole means of freeing treated
soil of foreign chemicals. To the micropopulation many of the pesticides merely
represent exotic carbonaceous substrates which are available to a small or large
segment of the community as sources of carbon or other nutrients. The avail-
ability of a pesticide as a nutrient will determine its slow or rapd dissipation
in the sofl, the rate depending upon the compound, the method of application,
the extent and degree of adsorption, the vigor of the active species, various
environmental factors, and possible toxicity of the substrate to microorganisms
using it.
Generally the factors that render a pesticide molecule biodegradable are not well
understood. Slightly soluble, highly chlorinated pesticides are generally most
resistant to microbial attack. 3 Many of the chlorinated hydrocarbon pesticides
fall in this category. Pesticides containing polar groups such as OH, t 1H 2 ,
=N-C(O)-, COO-, NO 2 , and a few others often provide a locus of attack to micro-
organisms. The rate of reaction is further influenced by steric and electronic
factors on neighboring atoms.
Whereas the climatic and edaphic factors favoring metabolism of pesticides are
well understood, the information on mechanisms by which microorganisms degrade
pesticides is quite scant. Presence of organic matter, nearly neutral pH, ade-
quate moisture, and warm soil temperatures generally promote microbial activity
and in turn enhance metabolism (biodegradation) of pesticides. Reduction of
nitro—groups and displacement of Cl. by H represent alternate reactions which may
be encountered under water-logged soil conditions. These reactions are also
usually more rapid than the oxidative pathways occurring in aerobic environments.

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Various substituents and linkages of the chemicals determine the degree of their
biodegradability. In this regard some generalizations can be made regarding the
effect of “hard” and “soft” linkages. Several linkages which are reported to be
readily biodegradable are as follows: carbamates (R-NH—CO2R’), anilides
(R—NI1—COR’), phosphates (-OOP=O-S—R, —OOP=O—O-R), and aliphatic acids (R-CHCL—COO—,
R—CCL2-COO-).’ The rate at which linkages are hydrolyzed will depend on the
nature of R and- R’. Few investigations have ever attempted to compare the
structural features necessary for toxicity to target pests with those permitting
degradation in the environment. Some information exists, however, for some of
the major classes of pesticides. For example, the most herbicidally active
structures of aliphatic acids are also the most readily biodegradable structures.
Increasing or reducing the chain length reduces herbicidal activity. Phosphate
insecticides display a wide range of stability towards biodegradation but are
generally regarded as not persistent. Phenylcarbamate herbicides, on the other
hand, are readily broken down by soil microorganisms.
Uptake of pesticides plants is another biological mechanism which to a degree
influences the fate of pesticides in the soil. Both cultivated and non-cultivated
plants may assimilate through their roots a variety of pesticides and thereby
lower the concentration of these chemicals in the ecosystem. Uptake of pesticides
by plants is desirable when the plants are weeds or the pesticides are systemic
insecticides or fungicides; it is undesirable when persistent residues remain in
portions of the plant used for food or feed. It can be generalized that any
organic pesticide introduced into a plant may undergo degradation, modification
of structure, or condensation with natural plant constituents. Often a detoxi-
fication mechanism may consist of simple conjugation of pesticides with carbohy-
drates, proteins, amino acids, etc. There are, however, many unknown factors
regarding the fate of pesticides in crops. In general the translocation of toxic
chemicals throughout the plant depends upon complex and interrelated morphological,
physiological, biochemical, and physical factors. The complete picture is quite
unclear, as some pesticides are applied in one form, translocated in a changed
form, and are inhibitory in still another form. Many other chemicals, however,
remain unchanged.
RECENT ADVANCES IN DEVELOPING MORE RAPIDLY DEGRADABLE PESTICIDES
The injurious effects of pesticide use could be most efficiently overcome by
completely halting the use of pesticide chemicals and replacing them with biologi-
cal methods of control. This alternative possibly represents the ideal situation
from an ecological standpoint, but many experts believe that it will be years or
even decades before biological methods can assume any significant part of the
burden of controlling pests. In the interim, they maintain, chemical control
is the only answer. 6
Nonetheless, the dangers involved in the use of pesticide chemicals could be
substantially reduced by i) the selection of alternate, less hazardous pesticides,
or 2) the development of new, safer, more selective chemicals.
According to the U. S. Department of Agriculture, more than three-quarters of the
organochlorine pesticides used by farmers on cotton, corn, peanuts, and tobacco
could have been replaced by less persistent insecticides without affecting pro-
duction as far back as 1966.6 However, these alternative pesticides are likely
to be more expensive when only the cost of the pesticide material is considered
because they may be someWhat less effective against given pests and, therefore,
required in larger quantities than the harsh organochlorines. 7 This may in part
explain the fact that the use of chlorinated hydrocarbon insecticides has not been
ctrrtailed but rather increased since 1966 until federal legislation regulated
their use. However, realistic considera tion of the cost of any pesticide cannot
be based solely on the output required to purchase and apply the pesticide but

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must also consider any Injurious effects, whether accidental or otherwise. 7 With
the organochlorines, for example, costs involved in monitoring for environmental
residues must be considered. With highly toxic compounds, costs of medical ex-
penses and time lost through employee illness are factors to be dealt with in
determining the overall cost.
A realistic cost/benefit assessment using this approach tends to favor the use of
non—persistent pesticides which entail fewer environmental dangers. Further,
some experts contend that it is feasible, on the basis of present knowledge, to
substitute pesticides of low persistence and toxicity for the more hazardous ones.
The dairy industry, for example, has successfully eliminated the use of persistent
organochlorine insecticides in the production of feeds and forages and in the
control of insects affecting dairy cattle. Similarly, the USDA has discontinued
the use of dieldrin in preference to lou—volume malathion sprays for control of
grasshoppers, and the use of methoxychlor and sanitation instead of DDT for the
control of Dutch Elm disease has drastically reduced the hazard to bird populations.
The use of alternatIve pesticides, however, may not improve the situation but may,
in fact, worsen it. 0 For example, use of Azodrin, a relatively non-persistent
organophosphorus insecticide, as a •substitute for DDT and toxaphene, both of which
are persistent organochiorines, to control the cotton boliworm in.the southwestern
U.S. resulted in the death of a large number of dove and related birds. Similarly,
carbaryl, a relatively non-persistent carbamate insecticide which displays low
toxicity to vertebrates, is quite toxic to bees. The use of this compound has
resulted in the destruction of many apiaries and consequent damage to pollination
of crops and other plants.
In addition, it may be that in some situations the costs involved in the use of
alternative pesticides are prohibitive or that suitable substitutes are not
available. Under these conditions, one must rely on the development of new, safer
pesticides. The cost of developing these new pesticides - an expense which must
be realized upon marketing of the product - is staggering. The cost of bringing
a single new compound to market,has risen from $1,196,000 in 1956 to $L ,060,4 3 6
in 19699 to $5,500,000 in l 97 O. Moreover, the overall chance of success for an
experimental product of this type, one in 1,800 in 1956, has dropped considerably.
Estimates of a new product’s chance of success on the 1969 market range from one
in 5,OLI09 to one in 36,00010 with the latter authors setting the odds for a new
product to attain a sales volume of over $5 million/year as only one in 360,000.
These estimates clearly illustrate that the search for new ç esticides may well
meet with diminishing returns.
Despite the increasing chance of econ mic failure, new pesticides are being
marketed, generally for the express purpose of combating environmental pollution.
For example, S. B. Penick and Company has produced an insecticidal material
trademarked as SBP-1382. 11 This compound is a synthetic pyrethroid produced by
esterification of 5—benzyl-3-furylcarbinol, a raw material produced chemically,
and cis-trans chrysanthemic acid. It is designed for use in the control of both
flying and crawling insects, effects the same degree of insect toxicity as the
pyrethrin insecticides, but is less toxic to mammals than the pyrethrins.
Along this same line, research workers at the University of Illinois under the
direction of entomologist Robert L. Metcalf have developed seven new insecticidal
chemicals. 12 All are DDT analogs and are as effective as DOT against flies and
mosquitoes. Two of the analogs, 1,1,1-trichloro-2- methoxyphenyl,2— 2 -
methylthiophenylethane and 1,1,1—trichloro-2—p-ethoxyphenyl,2—p—methoxyphenylethane,
are especially promising in that they are more selective than the broad spectrum

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DDT white equally as toxic to flies and mosquitoes. In addition, DDT—resIst nt
strains of these Insects appear to be susceptible to these analogs, while the new
compounds are distinctly less toxic to higher animals. The new analogs are also
less persistent than DDT and upon degradation they are converted to water soluble
metabolites which are rapidly excreted instead of being stored In fatty tissues
(as are water—insoluble degradation—products).
New herbicide formulation and combination promise greatly increased effectiveness
and safety in control of aquatic weeds. A combination of 1+ ppm of CuSOk and
1 ppm of diquat gives more effective and prolonged control of hydrilla than
20 ppm of CuS0L or 3 ppm diquat alone or any of the numerous other herbicides
and mixtures that have been tested. The combination assures greater safety for
fish, reduces the chemical cost substantially, and greatly diminishes the danger
of accumulation of residues in water. 13
Furthermore, a new granular formulation of an amine salt of endothall provides
control of hydrilla comparable to much greater rates of liquid formulation pre-
viously used. It confines the chemical residues mostly to the bottom two feet
of a lake or pond, reduces the amount of herbicide required, and eliminates or
greatly reduces the fish toxicity involved in use of liquid formulations.’ 3
Pilot control studies employing short—lasting insecticides were conducted on
lk,231 acres in Idaho and Washington. A new stabilized formulation of pyrethrum
showed promise in controlling the hemlock looper. Zectran applied In very fine
droplets failed to meet control criteria in controlling the spruce bud worm.’ 3
Benomyl may be a promising fungicide for the control of Dutch elm disease.
Benomyl was readily taken up by the seedling roots and by a newly developed
technique, detected.throughout the plant. The recent synthesis and development
of several synthetic fungicides have given new impetus to the search for
chemotherapeutic agents which will control the Dutch elm disease. This approach
is especially significant since DDT up until recently has been the major chemical
control for this pest.
Recently several advances have been made in the discovery of effective systemic
fungicides. One of• the materials which is effective chiefly a9ainst basidlomycetes
(rusts, smuts, bunt of cereals, etG.) Is the 1,14_oxathiins.1 ,15 Specifically,
carboxin (2,3-dihydro—5—carboxanilido-6-methyl—1,l4—oxathiin) has shown great
promise as a seed treatment for the loose smuts. A closely related derivative,
carboxin dioxide (2,3—dihydro—5—carboxyanllido—6-methyl-1,k—oxathiin— ,k-dloxIde),
is effective against the rusts. 6
Two benzimidazolederivatives, the TBZ 2-(L -thiazolyl) benzimidazole, and benomyl
(methyl 1-(butylcarbamoyl)—2-benzlmidazole—carbamate) have systemic Rropertles
and are effective against fungi, both foliar and soil pathogens. ’ 7 ’’°
Even as investigators search for “soft” pesticides to replace the more dangerous
compounds, and as suppliers strive to produce new and safer chemicals, there
exists a growing trend toward the rejection of all synthetic agricultural chemi-
cals in favor of naturally produced materials, and It may well be that more
attention should be focused on natural products for aid in pest control. One
facet of this overall area is the use of microbiological products as pesticide
chemicals.
In the course of the life cycle of any microbiological population, thousands of
chemicals are synthesized, quite a few of which have been found useful in the
service of man. The best known of the compounds, of course, are the antibiotics,
which inhibit the growth and replication of other microorganisms. 19 Since the
mode of action of many antibiotics involves interference with processes basic
to all forms of life, it is entirely reasonable that some of these microbial

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products should affect the development and functioning of insects. The effect
of microbial antibiotics on various insect pests has been thoroughly reviewed) 9
The codling moth ( Carpocapsa pomonella ) was found to be quite susceptible to
novobiocin. 2 ° When a 150 ppm solution of this antibiotic was applied topically
to female moths, 100 per cent mortality was achieved in three days. Similar
results were obtained upon treatment of the green peach aphid ( Myzus persicae )
with novobiocin. However, novobiocin displayed a selective type of toxicity
in that the closely related apple aphid ( Aphis phomi ) and pea aphid ( Acyrthrosiphum
pisum ) were unaffected. Similar selectivity with respect to target organisms
was observed with cycloheximide, which was highly toxic to the rice stem borer
( Chilo simplex ) and the green peach aphid, moderately toxic to the apple aphid,
and non—toxic to the pea aphid.
Xanthomycin and actinomycin A had respective LD 50 values of 2k and 58 micro-
grams/insect when administered by ingestion to German cockroaches. 21 The LD5O
value for xanthomycin, however, was 3.6 micrograms/insect when the antibiotic
was injected into the cockroaches, indicating that methods of application are
very important factors in determining the insecticidal properties of these
compounds. Actfnomycin A was not toxic to the black carpet beetle ( Attagenus
piceus) , but did act as a repellent when impregnated in wool fabric. 22
Considerable effort has been directed toward stored grain weevils and their
possible control by antibiotics. Moderate mortality of the granary weevil
( Sitophilus grarlarius ) and a rice weevil ( Sitophilus oryzae ) occurred when the
grain was treated with oxytetracycline 23 while streptomycin had no appreciable
effect. Chlorotetracycline was highly toxic to two other rice weevils ( Calandra
oryzae and Calandra sasakii ) whereas oxytetracycline was far less effective.
These examples represent but a few of the bacterial antibiotics which, because
of their toxicity and selectivity, and because they are produced naturally by
biological systems, may well deserve attention as potential insecticidal chemicals.
Investigation of the mode of action of these antibiotics in Insects has led to
the conclusion that, in general, these compounds are toxic because of the dis-
ruption of the protein synthesis process, either in production of messenger RNA
from DNA or in the actual synthesis of the protein at the ribosomes.’ 9 Inhibition
at either stage, however, would result in no protein synthesis.
One aspect of the overall idea of microbial toxins as insecticides which deserves
special attention is the bacterial toxin produced by Bacillus thuringiensis ,
the first microbial insecticide to be commercially developed. The pathogenicity
of this bacterium was or inally thought to be due to the presence of either
bacterial cells or spores, but it is now clear that the pathological effect of
B. thuringiensis is due to the presence of toxins. Germination of spores and
multiplication of the organism in the host is a secondary phenomenon. 19 Five
toxins are produced by this bacterium. These are (1) parasporal crystals, (2) a
thermostable toxin Y—exotoxin), (3)S—exotoxin (lecithinase), (k) proteinase,
and (5) a boullogenic antibiotic. However, only the,0 —exotoxin has a molecular
structure simple enough to be characterized fully and produced chemically.
In addition to bacterial species which may adversely affect the life cycle of a
given insect, fungi are also active in this regard. Members of the phycomycetes,
ascornycetes, and especially deuteromycetes (fungi imperfecti) classes have been
known to be pathogenic to insects for many years. Although these pathogens
generally destroy their target insect by multiplying rapidly within the insect’s
body, it may well be that the production of toxic materials is an important
part of the infection process, and these chemicals may have the potential for
use as insecticides. 19 Little investigation, however, has been done concerning
the insecticidal capacities of mycological toxins in the absence of the furgus
which produced them.

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SUMMARY
In order to feed and clothe all people, man must use pesticides. However, he must
also be conscious of the behavior of these harmful chemicals in the ecosystem,
especially where their presence might affect his own welfare. Investigations
concerning the fate of pesticides in soil have shown that pesticide detoxifica-
tion proceeds by two mechanisms: physicochemical (adsorption, movement, photo-
chemical decomposition, and chemical reaction), and/or biological (microbial
breakdown and plant uptake). However, since many of these studies have been
limited in scope and qualitative m i nature, considerable research must still be
performed to fully understand the ultimate fate of pesticides in soil.
Future development of new pesticides should be concerned with chemicals which
are more selective and biodegradable than many of the presently used pesticides.
As these new compounds are developed, their behavior in the environment must be
determined before they are made commercially available.
RE FERENCES
1. Sharvelle, E. G. 1961. The nature and use of modern fungicides. Burgess
Publishing Co., Minneapolis, Minn.
2. Bailey, G. W. and J. L. White. 1970. Factors influencing the adsorption,
desorption, and movement of pesticides in soil. Residue Reviews. 32:29-92.
3. Helling, C. S., P. C. Kearney, and M. Alexander. 1971. Behavior of pesti-
cides in soils. Advances in Agronomy. 2 3 :1L 7_2L 0.
k. Crosby, D. G. 1970. The nonbiol.oglcal degradation of pesticides In soils.
In Pesticides in the soil: ecology, degradation, and movement. Interna-
tional Symposium on Pesticides In the Soil. Michigan State University,
Feb. 25—27.
5. Kearney, P. C., and J. R. Plimmer. 1970. Relation of structure to pesticide
decomposition. In Pesticides in the soil: ecology, degradation, and move-
ment. International Symposium on Pesticides in the Soil. Michigan State
University, Feb. 25—27.
6. American Chemical Society. 1971. Pesticides: consumer fear of ill effects
grows. Chem. and Eng. News L 9(32):16_18.
7. Moats, Sheila A., and W. A. Moats. 1970. Toward safer use of pesticides.
BioScience 20:Lf59_k64.

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8. U.S. Department of Agriculture and Office of Science Technology. 1969.
Pesticides in the environment. pp. 67—82. In A report to the President on
control of agriculture-related pollution. Washington, D. C.
9. von RUmker, R., H. R. Guest, and W. M. Upholt. 1970. The search for safer,
more selective, and less persistent pesticides. A questionnaire survey of
pesticide manufacturers. BioScience 2O:1O0L _1OO 7 .
10. Neumeyer, J., D. Gibbons, and H. Trask. 1969. Pesticides. Chem. Week,
April 12, p. 38—68 and April 26, pp. 38-68.
11. Miller, D. D. (ed.), SBP—1382—New man—made insecticide. 1971. Pest Control
39(7) :18.
12. American Chemical Society. 1971. DDT substitutes. Chem. and Eng. News.
49(31) :7.
13. Gibbs, L. C. 1971. Changing pesticide patterns. pp. 251—262. In Study
book for the introductory course: pesticide5 and public health. EPA.
Atlanta, Ga., May 11-14.
14. Edgington, L. V., G. S. Walton, •and P. M. Miller. 1966. Fungicide selective
for basidiomycetes. Science 153:307—308.
15. von Schmeling, B., and M. Kulka. 1966. Systemic activity of 1, 4 -oxathiin
derivatives. Science 152:659-660.
16. Torgeson, D. C. 1972. Fungicides and nematocides: their role now and in
the future. J. Environ. Quality 1:14—17.
17. Delp, C. J., and H. L. Klopping. 1968. Performance attributes of a new
fungicide and mite oricide candidate. Plant Dis. Rep. 52:95—99.
18. Staron, T., and C. Allard. 1964. Proprietes antifongiques du 2—( 4 ’thiazolyl)
benzimidazole ou thiabendazole. Phytiat. Phytopham. 13:163-168.
19. Huang, H. 1., and M. Shapirp. 1971. Insecticidal activity of microbial
metabolites. pp. 79—112. In D. J. D. Hockenhull (ed.) Progress in industrial
microbiology. Vol. 9. J. and A. Churchill, London.
20. Harries, F. H. 1967. Fecundity and mortality of female codling moth treated
with novobiocin and other antibiotics. J. Econ. Entomol. 60:7—10.
21. Mengle, D. C., and F. W. Fisk. 1956. The toxicity of certain antibiotics
to the German cockroach. Antibiotics and Chemotheraphy 6:607.
22. KIdo, G. S., and E. Spyhalski. 1950. Antimycin A, an antibiotic with
insecticidal and miticidal properties. Science 112:172—173.
23. Musgrave, A. J., and J. J. Miller. 1951. A note on some preliminary
observations on the effect of the antibiotic terramycin on insect symbiotic
microorganisms. Can. Entomol. 83:343.

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THE NATIONAL PESTICIDE MONITORING PROGRAM
Herman R. Feltz
The National Pesticide Monitoring Program (NPMP) is sponsored by a Monitoring Panel
consisting of members appointed from agencies or components In the Departments of
Agriculture; Defense; Commerce; Interior; Health, Education, and Welfare, the
National Science Foundation; the Envirorunental Protection Agency; and the Tennessee
Valley Authority. Its principal functions are to promote a national pesticide moni-
toring program, to encourage development and use of uniform sampling and analytical
methodology, and to assure that the results of monitoring are effectively
disseminated.
Organizational Responsibility
The Monitoring Panel is one of five active panels of the Federal Working Group on
Pest Management (FWCPM), whose origin may be traced to the creation of the Federal
Pest Control Review Board. The Board was established in 1961 because of the concern
of President John F. Kennedy for interagency cooperation in the use of pesticides.
This was an advisory board composed of two members from Agriculture; Defense; Health,
Education, and Welfare; and Interior. It was charged to provide a joint review of
all major federal pest control programs, coordinating the activities of the four
departments. In 1964, in response to the 1963 Report of the President’s Science
Advisory Committee on Use of Pesticides, a charter was signed by the Secretaries of
the four departments, creating a new Federal Committee on Pest Control (FCPC). Sub-
committees on Program Review, Monitoring, Safety, Research and Information were sub-
sequently added to assist the parent FCPC in its broadened scope and responsibilities.
The replacement of the FCPC by the Working Group of the Subcommittee on Pesticides,
President’s Cabinet Committee on the Environment was announced by the White House in
November 1969. The charter of the Working Group was published in the Federal
Register on March 26, 1970. When Executive Plan III became effective in July 1970,
the Cabinet Committee on the Environment was dissolved, although the Working Group
continued to perform its functions. In October, by White House memo to the Chairman
of the Council on Environmental Quality (CEQ), the Working Group on Pesticides was
made responsible to CEQ. On November 23,1971, the Chairman of the CEQ approved a
new charter for the Working Group reflecting organizational changes within the
federal government, and changing the name of the Group to the Federal Working Group
on Pest Management. The following agencies have membership on the Working Group:
the Departments of Agriculture; Health, Education, and Welfare; Interior; Defense;
Transportation; State; Commerce; and the Environmental Protection Agency. The
Council on Environmental Quality, the Office of Science and Technology, the Office of
Management and Budget and the Office of Intergovernmental Relations may designate an
observer at the meetings of the Federal Working Group. Other agencies may be Invited
to participate.
The Federal Working Group is the primary staff level coordinating mechanism for -
federal activities concerning pesticides, pests and pest management. The activities
coordinated by the Federal Working Group include but are not limited to:

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a. Pest control programs in various parts of the world in which there is active
participation on the part of the federal government, either in funding or in
supervision;
b. Research on pests and their control and effects of management procedures,
whether by chemical or other methods;
c. Monitoring of the environment for pesticides and their residues;
d. Establishment of survey investigation teams to conduct special investi-
gations of problems which arise or which may be anticipated;
e. Public information on pest management and the use of pesticides;
f. Evaluation of economic and social values and risks involved in the control
or noncontrol of pests by various methods;
g. Development and coordination of safety measures in the use and disposal of
pesticides; and
h. Training programs that will result in an adequate level of competence by
federal employees in utilizing and prescribing various control techniques.
The Federal Working Group advises the Council on Environmental Quality and the
appropriate federal departments and agencies concerning matters of common interest.
In no case, however, does the Federal Working Group supersede the responsibility of
each agency to carry out the functions assigned to it by legislative and executive
mandates. The Federal Working Group encourages an exchange of information among
international, fedetal, state and local agencies, and participates with them as
appropriate.
In due course, the charter of the Monitoring Panel will be rewritten to reflect
responsibilities consistent with the charter of the Working Group. Of significance,
is that the role of “Monitoring’ t is succinctly stated, and placed in perspective with
charges to the other panels: Program Review, Research, Safety, and Information.
Program Description
The National Pesticide Monitoring Program (NPNP) was first described in the
Pesticides Monitoring Journal (PMJ), Vol. 1, No. 1 (1967). The Program was
initially designed on the basis of the minimum monitoring needed to establish base-
line levels of pesticides in food and feed, humans, soil, water, air, wildlife, fish
and estuaries, and to assess changes in tl se levels. Monitoring activities are
subject to continuous change—-to incorpor te research investigations, utilization of
improved methodology, modification o reflect changes in program emphasis, and to
accommodate findings within existing programs. In 1968, a review of the components
of the National Pesticide Monitoring Program was initiated by the original Sub-
committee on Monitoring. Program design criteria were straightforward, calling for
component monitoring on a random basis to continually assess pesticide levels and
define problem areas. The review has been completed by the Subcommittee’s successor,
the Monitoring Panel of the Federal Working Group on Pest Management, responsible to
the Council on Environmental Quality.
Recent realignments have been made in the pesticide activities of the federal
agencies; and, although the focal point of federal policies and activities for
environmental monitoring is within the Environmental Protection Agency, many of the
monitoring activities on pesticides remain in other agencies. The revised programs
were published in the Pesticides Monitoring Journal , Vol. 5, No. 1, June 1971.

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The Monitoring Panel defines monitoring as “repeated sampling of environmental com-
ponents to obtain data on pesticide residue levels in reference to an arbitrarily
defined base line.” Monitoring of each component in the program is conducted by a
federal agency or its cooperators. The design for sampling is reviewed by this Panel
of the Working Group to ensure national coverage in terms of defining levels and
“problem—finding.” Agencies conduct this monitoring as a part of, or in addition to,
their own mission-oriented monitoring. Participation in the NPMP, under ever
increasing budgetary constraints, exemplifies interagency cooperation.
Details of the monitoring program for each of the components can be examined in the
Journal ; a summary, however, seems appropriate.
Food and Feed
The Federal program for monitoring pesticide residues in food and feed is comprised
of surveillance programs maintained by the Food and Drug Administration. U.S. Depart-
ment of Health, Education, and Welfare and by the Consumer Protection Program, Con-
sumer and Marketing Service, U.S. Department of Agriculture. The Department of
Agriculture is responsible for the sampling of meat and poultry, and DHEW is
responsible for raw agricultural products and the Market Basket Studies.
The objective of this program is to determine the levels of pesticide residues in
unprocessed and commercially processed consumer food commodities, animal feeds, and
composites of food items prepared for human consumption. Programs being carried out
to accomplish this objective include (1) a continuing Market Basket Study to deter-
mine pesticide residues in the basic 2—week diet of a l6—to-19—year—old male, sta-
tistically the Nation’s largest eater, (2) nationwide surveillance of unprocessed
food and feed, and (3) the surveillance program of the Consumer Protection Program,
Consumer and Marketing Service, U.S. Department of Agriculture, for the analysis of
meat and poultry samples taken from animals at slaughter.
An emerging and very important objective of this program is to determine levels of
contaminants not directly attributable to pesticide application e.g. mercury, poly—
chlorinated biphenyls, cadmium, etc. To the extent that methodology and program
mechanics are interrelated with pesticides, determination of such contaminants has
become an automatic objective of this program.
Humans
The purpose of the human monitoring program is to determine on a national scale
levels of pesticide incidence in the general population and to assess changes in
these levels. Such incidence reflects prior exposure from all s urces and is impor-
tant in understanding the etological impact of pesticides pollution and in studying
the human health effects of pesticides exposure. Man may be exposed to pesticides
through contact with any of the elements of the environment, including air, water,
food, soil, and house dust, as well as in the course of some occupations and hobbies.
Exact measurement of man’s total exposure to pesticides requires careful development
and implementation of plans, the full cooperation of willing subjects, and adequate
laboratory support——conditions which can be attained only in the controlled research
situation and are not easily applicable to large groups. Previous human exposure to
pesticides may be estimated from measurement of storage levels or excretion of these
materials or their metabolites and from measurement of physiologic effects. No one
of these approaches can be used to assess exposure to all pesticide chemicals. Some
available methodologies are suited to research projects but not to field surveys in.
volving large numbers of samples.

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Fish
Beginning in the fall of 1970, 50 new stations were added to the original 50 stations
sampled annually by the Bureau of Sport Fisheries and Wildlife for monitoring pesti-
cide residues in fish. The original 50 stations, sampled since the spring of 1967,
will be retained in the expanded program.
Three composite samples, each containing 3—5 adult fish of a single species, will be
collected. All composite samples will be replicated for a total of 600 samples
analyzed annually. Residue analyses will be performed for the identification and
quantitation of DDT, DDE, TDE, dieldrin, aldrin, endrin, BlIC, heptachlor, heptachior
epoxide, chlordane, toxaphene, mercury, arsenic, and lead. Samples will be screened
for the presence of interfering polychlorinated biphenyl compounds (PCBts). Fish
will be collected and handled in such a manner as to prevent contamination of the
sample with extraneous chemicals.
Wildlife
Early in the development of the wildlife monitoring program, certain criteria were
recognized as being important in the selection of species of wild animals suitable
for pesticide monitoring purposes. Ideally, the forms selected should be geo-
graphically well distributed, and they should be reasonably abundant and readily
available for sampling. In addition, animals occurring near the top of food chains
have the capacity to reflect residues in organisms occurring at lower levels in the
same food chains. Based on these criteria, species chosen for monitoring include the
starling ( Sturnus vulgaris) , mallard ( Anas platyrhynchos ) and black ducks ( Anas
rubripes) , and the bald eagle ( Haliaeetus leucocephalus) . The black duck is substi-
tuted for the mallard in States where suitable numbers of mallards cannot be obtained.
The Bureau of Sport Fisheries and Wildlife is held responsible for the execution of
the wildlife portion of the National Pesticide Monitoring Program. The primary
objective is to ascertain on a nationwide basis and independent of specific treat-
ments the levels and trends of certain pesticidal chemicals and other pollutants in
the bodies of selected forms of wildlife. The program was first described by Johnson
etal. in 1967. The purpose of this report i s to update and redescribe the wildlife
monitoring program and briefly review accomplishments.
Estuaries
The estuary is the habitat of a wide array of fish, shellfish, and other biota that
have considerable coinmerical importance as well as value as game. species. Ter-
restrial appli.cation of persistent pesticides results in their being carried in
surface waters and, through adsorption on silt and debris, transported through river
basins eventually into estuaries. Here, their chronic presence at subacute levels
might cause irreversible changes before their presence is apparent.
Studies have shown that clams and oysters are particularly well suited for pesticide
monitoring; these sessile forms will tolerate chlorinated hydrocarbon pesticides and
retain the residues for extended periods following exposure; also, they are abundant
and easily handled.
Samples for analyses are collected by agencies at both the Federal and State level
from estuarine systems and major river drainages containing commercial quantities of
shellfish. In the interest of continuity, uniform sampling procedures are observed.
by each cooperating organization. A total of 170 stations have been selected for
monthly samples of either oysters or clams in 15 coastal States. Sampling points
within an estuary are selected on the basis of hydrographic data and the avail-
ability of suitable shellfish populations.

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Water
The current design of the program for monitoring pesticide residues in the hydrologic
environment is a revision of the program initiated in 1967 by the Federal Water
Pollution Control Administration and the U.S. Geological Survey and provides for a
continuing assessment of the general levels of pesticides in the water and bottom
sediments of the Nation’s water courses.
Water samples collected quarterly and bed material samples collected semiannually at
161 sites in the conterminous United States, Alaska, Hawaii, and Puerto Rico will be
examined for the presence of pesticide residues. Sampling sites were chosen at
random from hydrologic units within the major drainage basins defined by the Water
Resources Council. Analyses will be performed using separation and identification
techniques currently acceptable to the scientific community.
Soils
The agricultural pesticides monitoring program was initiated in 1964 with the
establishment of large-scale study areas in the Mississippi Delta; Grand Forks, N.
Dak. and Yuma, Ariz. The determination of pesticide residue levels in the soil was
an integral part of the study. An additional large-scale study area was established
at Mobile, Ala. in the spring of 1965. Also during 1965, the soils phase of the
program was expanded to include sampling sites in 17 high—use, 16 low-use, and 18 no-
use areas across the United States. The large—scale study areas were phased out at
the end of 1967. Selected fields in these areas and the high—, low-, and no—use
areas will be resampled periodically.
Results of these pilot studies, including analytical data for soybeans, carrots,
peanuts, and potatoes, indicated a need for a nationwide monitoring program to assess
the pesticide residue levels in the soils more thoroughly.
The objectives of the soil monitoring program are as follows:
(1) To determine levels of pesticide residues and major pollutants in soils in
major land-use areas and other areas in the United States and through periodic
sampling, to determine changes in these levels.
(2) To determine the levels of pestthide residues in crops grown on treated
soil and other components of the environment directly related to the soil.
(3) To determine the level of pesticide residues in runoff water of certain
agricultural lands. -
(4) To provide a basis for initiation of special studies on demonstrated
problem..areas.
(5) To publish the results for appropriate distribution.
Air
Data on pesticides in air should be developed without special consideration for any
one sector of the environment such as man, wildlife, etc. In order to do this the
country should be divided on an arbitrary basis, i.e.. along longitudinal and lati-
tudinal lines or by some other grid mechanism constructed of x number of equally
spaced lines east—west and number of lines north—south acioss the country. Samp-
ling should be conducted at approxImately 60 sites selected by random design.
A rough design for air monitoring can still be devised; however, the limitations of
the sampling equipment and analytical procedures selected for use will influence the

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length of sampling intervals and the time required for analysis of a sample. These
factors will critically affect the number of samples which can be analyzed by a
laboratory in a specific period of time.
The Panel notes that the scope of the existing estuarine monitoring program is
limited compared to other substrates, which is due in part to the responsible
agency’s primary mission and resources. Also, there is no operational National
Monitoring Program for pesticides in air, and no comprehensive information on this
important substrate is developed in other programs. The statement on air monitoring
outlines a program needed to develop minimal data which can be correlated with data
from other parts of the National Pesticide Monitoring Program.
Suxmnary
Through the NPNP, base-line levels of pesticide incidence have been established in
food and feed, humans, soil, water, wildlife, fish and estuaries in order to allow
an assessment of changes in these levels. Base lines are needed against which to
compare subsequent data to determine what is an increase or decrease in national
pesticide levels. Monitoring for a variety of pesticides is conducted in accordance
with recognized scientific procedures. A revised list of pesticides suggested for
monitoring was published in the PMJ, Vol. 5, No. 1, June 1971, to complement the
revised NPMP.
The Program is continually reviewed by the Monitoring Panel to assess necessary
changes. Urban soil samples have been added to the soil monitoring component of the
program. These, heretofore excluded, were considered to be important in view of the
contribution of pesticides from urban sources. Analysis of bottom sediments has been
added to the water monitoring program. Most components of the NP are now being
analyzed for selected environmental contaminants, such as PCB ’s and heavy metals.
Several articles describing results of the NP have appeared in recent issues of
the Pesticides Monitoring Journal . As data from other components become available,
they too will be published in the PMJ which is a journal of stature among
professional workers.
To fulfill the obligation of effective data dissemination, the Monitoring Panel is
currently evaluating all available data from each component of the Program for
correlation. Such an assessment makes it incumbent upon investigators to provide
timely and valid data.
The National Pesticides Program is listed’in the Global Network for Environmental
Monitoring, developed under the auspices of the National Academy of Sciences,
attesting to the merits of program efforts.

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DISPOSAL OF WASTE PESTICIDES: PROBLEMS AND
SUGGESTED SOLUTIONS
H. C. Johnson and L. P. Wallace
One of the many problems encountered in the disposal of our nation’s
solid wastes is the handling of toxic and/or hazardous materials includ-
ing pesticides. Within EPA’s Office of Research and Monitoring, the
Solid Waste Research Office (SWR) has been and is presently studying
effective means of handling and disposing of these hazardous wastes,
particularly pesticides. Because of their toxicity, some pesticides
must be detoxified before any disposal or reclamation processes can be
safely applied, while other pesticides can be disposed of directly.
Emphasis in this presentation will be centered on those solid waste
management systems which are applicable to, or hold promise for, the
disposal of pesticides and pesticide containers.
Land Disposal Methods
The sanitary landfill is currently regarded as the most important land
disposal method and consequently, considerable research is directed
towards improving this technique and assuring that the environment will
be properly protected when this method is used. If correctly located
and engineered, one of the most favorable qualities of the sanitary land-
fill is its ability to receive heterogeneous solid waste loads. These
loads vary from being relatively innocuous and chemically inert to being
putrescible and even toxic. It is, however, most important that the
requirements given in the following definition be met in order for a
facility to be considered a “sanitary landfill”:
Sanitary landfilling is a method of disposing of solid waste
on land without creating nuisances or hazards to public health
or safety, by utilizing the prtnciples of engineering to con-
fine the refuse to the smallest practical area, to reduce it to
the smallest practical volume, and to cover it with a layer of
earth at the conclusion of each day’s operation or at such
more frequent intervals as may be necessary.
For every sanitary landfill, and particularly those receiving such toxic
materials as pesticide residues, it is important to assure that there is
no contamination of nearby ground and surface waters. A Solid Waste
Research sponsored study is being performed by researchers at the Univer-
sity of Illinois on the hydrology of several solid waste disposal sites.
Data from the study are useful in evaluating the factors that control

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ground water and landfill leachate movement. Five different hydra-
geologic environments were selected for the study and piezometers were
installed in drill holes, strategically located to define fluid potential
distribution, and water samples were taken for chemical analysis. In
addition to total dissolved solids and chlorides, which are good indi-
cators of leaching, a host of chemical determinations were done on those
samples. The results were used to predict the best physical placement
of landfills to avoid leaching. No pesticides were detected in the
leachate during the time of the study.
At one in-house project, Solid Waste Research is operating a field-scale
landfill in Walton, Kentucky, to further study leachate movement and gas
formation. The cell being used has been lined with clay and plastic to
assure total collection of rainfall or applied water. Information from
this study will give further guidance in the safe operation of sanitary
landfills for hazardous materials such as pesticides.
Another land disposal system has been under investigation in Alkali Lake,
Oregon. Under the sponsorship of Solid Waste Research, scientists at the
Environmental Health Sciences Center at Oregon State University have been
studying the feasibility of transporting the waste liquor and by-products
from 2, 4-D and 2, 4, 5-T manufacturing process to an arid area in Oregon
where they are being diluted and applied to the land for natural degra-
dation. The 55—gallon drums used for transporting are chemically
cleaned, compressed, and buried or baled and reused as scrap metal. The
theory behind the project is that herbicides and pesticides do not have
an infinite life in the environment. In every instance where persistence
of pesticides in soil has been studied, it has been found that the
chemical disappears within acceptable time limits (2-3 years) to a level
of little biological significance. The factors causing the disappearance
are photochemical decomposition, chemical decomposition, microbiological
degradation, and physical factors such as adsorption, volatilization, or
leaching. The physical factors, however, only take the pesticides from
one place to another, they do not really make them disappear.
Data from trial applications at the site have supported the degradation
theory. Application to small plots have shown that very little vertical
or lateral movement occurs during the degradation period which has been
twenty months for 60 percent degradation. It is planned to start using
subsoil injection routinely for the waste liquor presently being stored
at the site.
In conjunction with this study, the Oregon State University group is
also investigating pesticide container cleanup in Kiamath Falls, Oregon.
Attempts will be made to chemically clean the containers to such a level
that they can be accepted for baling and placement in an electric fur-
nace for scrap metal recovery. Facilities for this study have been con-
• structed and cleanup investigations are presently underway. Liquids from
the cleanup operation will either be used as a pesticide or disposed of
at the Alkali Lake site. In order to make the container cleanup easier,
the researchers have faken an active role in persuading pesticide users

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to rinse their containers with water or with the formulation they
prepare, adding the rinse back to the prepared formulation. Laboratory
tests have shown that rinsing an emptied container three times with sev-
eral quarts of water reduces the .residual pesticide content by 90 percent,
affords the user a financial saving of $1/6.5 ounces if the pesticide
costs $20/gallon, and greatly facilitates the container cleanup process.
Oceanic disposal of solid wastes, including pesticides and other toxic
materials, may be an alternative to the sanitary landfill method; how-
ever, there are many questions to be answered before the Solid Waste
Research Office could endorse ocean disposal. The report from a con-
tract with the Applied Oceanography Branch of the Dillingham Corporation,
San Diego, California, described the nature and magnitude of present
ocean disposal practices. In connection with the study, on-site surveys
were conducted at 16 United States cities situated on or near the Atlantic
and the Pacific coasts, and the Gulf of Mexico.
Data from the study reveal that some 62 million tons of waste are being
disposed of at sea each year at a cost of $37 million, including dredg-
ing spoils but excluding outdated munitions. Methods employed for dis-
posal consist primarily of transporting the wastes in bulk or barrels
aboard self-propelled or towed barges. The majority of wastes are dis-
posed of in bulk form and discharged while the barge is underway. In
several cases, highly toxic chemical wastes have been carried to sea
aboard merchant ships as deck cargo. The containers were then discharged
in undetermined areas once the ship was 300 miles from land. However,
bulk industrial wastes are usually transported in tank barges certified
for ocean waters by the United States Coast Guard. In addition, United
States Coast Guard regulations regarding the bulk shipment of chemicals
by water must be adhered to. The Sparkling Waters is just such a barge
especially built to handle insecticides and other toxic chemical wastes
off the New York coast.
Recently, a final report was ‘received from a contract at Foster D. Snell,
Inc. in Florham Park, New Jersey on conditions necessary for decontami-
nation and combustion of organic pesticides and pesticide containers.
Work on this project has included:
1. Determining the temperature and rate at which pesticides burn
in their pure form while testing the combustion gases for CO, CU 2 ,
H 2 0, and intermediate organics.
2. Incorporating the same pesticides in a mass of material such as
sawdust, paper, burlap, cloth, polyethylene, and wood,and investi-
gating the burning temperature and rate and determining the combus-
tion products.
3. Low cost chemicals including nitrates and chlorates were incor-
porated in the pesticide and the pesticide-material mixtures above
to facilitate decomposition.

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The report indicated the structural and compositional requirements
necessary for combustible pesticide containers and the possible use of
polyethylene liners to aid combustion. It was shown during the course
of the project that representative pesticides were virtually volatilized
or sublimed when incinerated unless a binder was present to increase the
residence time in the flame. By using polyethylene, which under heating
or combustion conditions softens or degrades to products of lower mo-
lecular weights, the advantages of a liner and a binder were obtained
with one material and the pesticides studied could be essentially des-
troyed at temperatures normally achieved by burning wood, paper, card-
board, etc.
In all the thermal studies performed, less than five milligram amounts
of the pure pesticide chemical were used. Since some undesirable emis-
sions were detected under these conditions, bench and field studies with
larger samples need to be investigated before definite conclusions can
be drawn.
Destructive distillation (pyrolysis) of pesticides shows great promise
as a detoxification reduction method. It should leave an easily handled
residue and should thermally degrade effluent gases to acceptable limits.
Additional research is needed to verify the possibilities of this method.
A great deal of concern is being directed to recycling of waste material.
Some of the present barriers to increased reclamation and recycling are
technological in nature and others are economic. Success in overcoming
these barriers has the dual advantage of reducing the amount of waste to
be disposed of while conserving the nation’s natural resources. Cellu-
losic wastes, including wood, bark, sawdust, oat hulls, corn cobs,
bagasse, and other agricultural residues are generated in truly prodi-
gious quantities. Little, if any, significant portion of these wastes
is beneficially used and, since thçy are commonly burned, cellulosic
wastes often contribute to air pollution in areas where they accumulate.
Under a research grant, the Institute of Forest Products, University of
Washington, in Seattle, is developing a unique means for u.tilizing
cellulosic wastes which will at the same time allow safer and more eff i-
cient application of pesticides to the soil.
Some common properties of the wood and agricultural wastes are that they
consist predominantly of polymeric cellulose macromolecules; they con-
tain an abundance of replaceable hydrogen atoms, and all are biodegrad-
able. Since these waste materials are polymers containing replaceable
hydrogen atoms it should be possible to attach pesticides to these sub-
strates in the same way that acetic acid, for example, becomes attached
to cellulose inthe manufacture of cellulose acetate. Research has
shown that pesticides can be attached to such solid waste as sawdust,
bark, and lignin by means of ester linkages. Herbicides have been com-
bined with natural as well as synthetic polymers. The herbicides used
were 2, 4-0, 2, 4, 5-1, 4(2, 4, 5)-TB, and Dalapon. It was found that
each of these polymeric combinations prevented the germination of cer-
tain seeds longer than the herbicide alone under controlled laboratory

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conditions. Similar results have been obtained in field plots using
herbicides and in Costa Rica using the insecticide carbofuran. In the
Costa Rican study, it was found that a treatment with the pesticide-
polymer combination was effective for eight weeks as opposed to one week
for the pesticide alone. Plans are to repeat this study in Puerto Rico
where environmental conditions are quite different.
The practical implication of the ability to chemically bond pesticides
to cellulosic materials is that very large quantities of cellulosic
wastes, so treated, could be utilized as a mulch for gardens and in
agriculture. The pesticide in the mulch would be released in controlled
fashion with distinct advantages over present procedures for applying
pesticides to soils. Now, pesticides usually have rather short useful
lives because they may be degraded by bacteria to inactive metabolites,
or washed by rainwater into the subsoil where they are inaccessible to
pests they are intended to control. Also, and more important from the
public health standpoint, this leaching into the subsoil often means
that some rather stable pesticides, or their degradation products, find
their way into potable water supplies.
In contrast, if the pesticide were chemically combined with the poly-
meric solid waste, its useful life should be prolonged; attack by bac-
teria should be reduced; and the pesticide should not be leachable into
the subsoil and hence will not pollute streams and rivers. As the solid
waste-pesticide mulch lies on and in the soil, it will gradually decom-
pose, continually releasing the active pesticide over a long period of
time. With this technique the problems and potential errors of measuring
and diluting liquid concentrates are eliminated. Spillages of solids
are, of course, less likely than liquid leakages and are easier to rectify
when they occur. Controlled releases of the pesticides may also allow
lower dosages and fewer applications.
Another very important benefit from this project is the prospect it may
hold for development and use of extremely short-lived biodegradable
pesticides which, in combination with solid waste polymeric substrates,
would be sufficiently stable for practical use. For example, many
organophosphorous pesticides are liquid and are too dermally toxic to
permit their use by anyone other than an expert. Combinations of these
materials would perhaps render them safe, while not destroying their
biological activity. The currently “unuseable” pesticides are often
effective at much lower dosages than the superficially less hazardous
products that are not used in relatively massive amounts.
Composting of municipal and agricultural refuse is not widely used as a
means for solid waste disposal in the United States. However, there are
several compost plants in operation and one may reasonably expect to see
the continued composting of solid waste on limited scale in areas where
the product is marketable. A research grant to the Western Research
Laboratory of the National Canners Association, Berkeley, California, is
supporting a study of the fate of insecticides in composted agricultural
wastes. A substantial part of the fruits and vegetables received for

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preservation by canning or freezing is discarded as solid wastes. That
portion of the raw product which is discarded-—vegetable skin and rind--
generally has the highest level of insecticide residue, and this fact has
limited the use of such material as animal feed, and it also raises
questions about possible harmful effects of spreading composted cannery
wastes on agricultural lands. This concern is especially justified if
toxic degradation or transformation products remain in the compost mixture.
The Canners Association study aims to obtain a better understanding of
the mechanism by which insecticides are degraded by microbial or chemical
action during aerobic composting, and also to obtain information which
will make it possible to dispose of waste materials containing concen-
trated insecticide residues without hazard to public health. Insecti-
cides selected for the study represent examples of the three principal
classes: chlorinated hydrocarbons, organophosphates, and carbamates.
The selection of specific insecticides was based upon the extent of
usage in agricultural products, variety of chemical structure, and
availability of reliable analytical methods. These included: dieldrin;
parathion; Diazinon; p, p DDI; pentachlorophenol, and with further
studies planned for Sevin and Zineb.
During the study, breakdown products of several insecticides have been
identified and the varying effects of batch-type and thermophilic corn-
posting processes have been noted. The summary in a recent progress
report contained the following information:
1. Concentration of Diazinon and parathion rapidly declined in
both composting processes with the thermophilic process being the
more efficient. Breakdown products identified for Diazinon were
oxodiazinon and sulphotepp. Those identif led for parathion were
aminoparathion, p-aminophenol, and p-nitrophenol.
2. Continuous thermophilic composting caused some reduction in DDT
whereas the batch process had little effect. No breakdown products
have been identified.
3. Dieldrin was more efficiently degraded in the batch process and
none of its breakdown products have been identified.
4. Following the active compost period (120 days), the curing or
aging phase (180 days) of the process had little or no effect on
the insecticides.
The consideration of pesticide disposal is one facet of hazardous waste
disposal. In Section 212 of the Resource Recovery Act, Congress commis-
sioned a study on the feasibility of strategically locating national dis-
posal sites to safely process hazardous materials. The first phase of
this two-year study has been initiated through a contract to the Booz-
Allen Applied Research Company. Their responsibility is to make a survey
and list the quantities, location, generation rate, and present disposal
practices of our nation’s hazardous wastes. Throughout all the phases
of this study, pesticides will be given particular attention in hopes
that some safe and effective means of their disposal can be developed.

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SAFETY IN HANDLING AND STORING PESTICIDES
James J. Boland
In any given year a number of people become ill or die as a result of overexposure to
pesticides. The circumstances of exposure may include, among others, the child who finds
a pesticide improperly stored or carelessly placed in use and eats or drinks it, or a
workman in a formulating plant or farmer in the field who accidentally spills a pesti-
cide on himself but does not take the necessary action to decontaminate himself and seek
medical aid. Regardless of circumstance, most of the illnesses and many of the deaths
associated with pesticides could have been avoided.
Although our attention this morning will focus on safety precautions for the worker and
applicator of pesticides, perhaps a word should be said about the occasional user of
pesticides, the homeowner or weekend gardener. Although not desirable nor totally justi-
fiable, the availability to the homeowner of concentrates of pesticide materials, some in
the area of eighty percent, is easily documented by a casual perusal of existing pesticide
stock in some retail outlets.
In this instance, the product label is the best source of information. The product label
is an excellent source of information. Utilization in this case is synonymous with reading
the label. The information containel nn the 1 hel represents an investment on the part
of the manufacturer of 4 to 6 million dollars.
The label gives such information as active ingredient(s), mixing and application rates,
target organisms, indication of toxicity, warnings and specific treatment in case of
poisoning.
Frequently illness follows when the label is not read. State Services Branch workers’
have shown that sources of product information are frequently friends, merchants, etc.,
the information being passed by word of mouth. This circumstance will tend to predispose
the user not to read the label or the product may be transferred from friend to friend
via the “Coke” bottle route, often with tragic consequences.
In considering safety concepts in the manufacture, formulation, storage, transport and
application of pesticides, our approach should be to minimize worker hazard and preserve
the integrity of the environment. It is under the conditions of manufacture and formula-
tion that the danger of exposure is greatest, for these conditions usually involve the
handling of concentrated materials.
How may we insure worker safety under these conditions? Perhaps we want to consider two
approaches——one direct, the other indirect. The indirect approach may include, but is
not limited to, the following:
(1) Education — We will presuppose that the manufacturer or formulator is knowledge-
able concerning ãfe handling procedures. (This is something which you may have to deter-
mine to your own satisfaction.) A worker who understands the dangers of the product(s)
with which he works will readily recognize the importance and necessity of the precautions
he is to take. He can do much to insure his own safety. Toxicity, routes of absorption,
signs and symptoms and instruction to seek medical aid if he has or thinks he has had an
exposure, are points to be incorporated into his educational program.

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(2) Personal hygiene - By stressing such factors as washing prior to eating/smoking,
daily shower and clothes change, much can be done to insure worker safety.
(3) Medical supervision - Periodic testing of blood cholinesterase activity and/or
metabolite excretion will generally serve to detect trouble in a worker who is experiencing
an undue exposure and is in danger of perhaps developing a toxic illness.
Protective devices and clothing which physically prevent exposure to pesticide materials
are classified, for the purpose of this discussion, as direct methods designed to minimize
hazards associated with pesticide processes.
Routes of entry—-dermal, oral and respiratory--are all important to the worker. The dermal
route of exposure is the most significant to persons involved in the manufacture, formula-
tion or application of pesticides. Wolfe 2 and his coworkers in Washington State have
shown in a study of several hundred pesticide applicators that over 97 percent of the pesti-
cide to which the body was subjected was deposited on the skin. This was especially true
of applicators applying liquid sprays. The importance of protecting the body surface from
contamination is obvious.
Factors such as fatigue, carelessness, boredom with the routine of many plant operations
and the sheer bulk of many of the pesticide product elements would be important considera-
tions when we consider the causes of some spills. Gross contamination of workers and their
environment is the end result, with concomitant health hazards.
Work by Maibach and Feldmann 3 in California showed that pesticides are more readily absorbed
from some body areas than others. Using C 14 labelled parathion as a representative com-
pound, these investigators found the range of absorption to be from 9 percent forearm to
100 percent in the scrotal area. Saturation of clothing with parathion or like substances
that are readily absorbed across the intact skin through spillage or saturation by sprays
would be akin to an injection of the material directly into the vein.
The importance of this last observation takes on added importance when we think for a mo-
ment about the tendency to carry objects or packages which are heavy or unwieldy in the
so-called “gut” carry position.
While cloth provides some degree of protection, waterproof trousers are recommended. A
waterproof apron would be second choice. Daily changes to clean clothing and daily shower
are both important adjuncts to direct protection of the lower body.
Absorption is somewhat less efficient over the upper body; this area still has a significant
exposure potential because of the large body surface. A waterproof jacket or raincoat with
long sleeves and a close-fitting neck should be used. This gives protection to the upper
back, shoulders and forearms of the worker.
The principal objection to the types of protective gear we are speaking about is that in
hot weather it becomes very uncomfortable. Worker comfort is in fact an important con-
sideration. Worker discomfort will frequently result in our “well protected man” being
seen by mid—morning wearing a T—shirt and baseball cap. What should be encouraged under
extreme heat conditions is at least insuring minimal protection by use of a long-sleeve,
GI-type cotton twill shirt which should be laundered after each use and changed when It
becomes wet with spray. This should never be considered adequate protection, but merely
a compromise between nothing and at least minimal protection.
Protective clothing of the lighter colors can be as much as 8 - 10°F cooler than the
familiar black or dark green type.
In the head and neck area Maibach etal. found absorption of parathion to be 32 - 47 per-
cent of the applied dose.”

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Headgear with a bill or brim will give some protection to the scalp, face and neck area.
A waterproof hat with a wide brim is available that affords good protection to this area
of the body.
Goggles and respirators provide considerable protection to the face area but should be
properly cleaned, serviced and stored.
The high potential exposure to the hands emphasizes the need for wearing globes. Cloth—
type gloves are not recommended as they can become soaked with pesticides and then enhance--
not prevent-—exposure. Rubber gauntlet—type gloves provide the best protection. The
gauntlet should cover the wrist, and the glove can be turned out for easy cleaning.
Waterproof shoes or boots provide the best protection for the feet. The trouser leg should
be worn outside the boot or shoe top to prevent runoff from going into the boot. Leather
work boots become dried and crack when repeatedly soaked with pesticide liquids; this makes
them unacceptable as protective gear when handling toxic materials such as pesticides.
Adequate respiratory protection for most types of application is provided by the use of
cartridge-type respirators. In some instances, such as manufacture or formulation of
extremely toxic products, self-contained or supplied—air type breathing apparatus is used.
The oral route of exposure probably is not one of major concern in occupational exposure.
It is usually difficult to make a clear distinction between oral exposure and respiratory
exposure. Few workers would intentionally eat these products with which they work. Pesti-
cide residues may be on the hands and transferred to lunch or snack items. Therefore,
washing before eating and smoking is the best prevention for this type of exposure.
Let us now consider the safe handling of pesticides in other important areas——transportation
and storage.
Pesticides may be shipped as the technical material——usually this is the undiluted chemical
of up to 95% pure material——or as formulations which are mixtures in which the technical
material is combined with a carrier or solvent permitting conventional application.
Hazards to workers in the event of a spill in transit, occur through the same mechanisms as
those considered earlier. That is, they may be absorbed, inhaled or ingested. This may
occur through contamination of items which are co—shipped or during the cleanup process.
Ingestion may occur if contaminated foodstuffs are allowed to reach consumers. Pesticides
cannot be shipped with foodstuffs unless they are packaged in air—tight wrappings. Un-
fortunately this regulation is sometimes ignored or wrappings break and the danger of
secondary poisoning still exists.
Cleanup involving pesticides should be performed only by authorized persons. These per-
sons should use adequate measures to protect themselves in the situation including measures
discussed above.
The National Agricultural Chemicals Association has formed a network of safety teams to
minimize the risk of injury from the accidental spillage or leakage of pesticides.
This network became operation in March of 1970. By contacting a central telephone number
(513 961—4300), the team network insures that expert help will be dispatached to the scene
of an accident. The safety team network furnishes personnel , equipment and expertise, to
insure prompt, efficient cleanup and decontamination following major accidents involving
pesticides.
Another form of assistance in general chemical emergencies is the establishment and func-
tion of the Chemical Transportation Emergency Center (CHEMTREC), established by the
Manufacturing Chemists Association (MCA).

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The CHEMTREC number is 800 424—9300; in Washington, D.C., the number is 202 483-7616.
The Department of Transportation, Office of Hazardous Materials is assisting in the dis-
semination of information concerning the newly established central information point for
Chemical Transportation Information (CHEMTREC).
The Chemical Transportation Emergency Center (CHEMTREC) provides emergency personnel with
information on safety measures in handling hazardous chemicals involved in accidents on
the nation’s highways, railroads and waterways. A voluntary program of the Association,
which has 165 u.s. member companies, CHEMTREC operates on a 24—hour basis, seven days a
week with a nationwide telephone number.
CHEMTREC is not a source of general chemical industry information, such as how to locate
a missing shipment; nor is it a policing agency. It is a source of assistance to official
organizations concerned in chemical transportation emergencies and is designed to provide
immediate data on how to handle these emergencies to those who are trained to do so. The
Manufacturing Chemists Association initiates this new program to protect emergency crews
and the public has been in development for the past 15 months.
Further information may be obtained by writing either the MCA or the Department of Trans-
portation, Washington, D. C.
The danger of fire in warehousing pesticides is a major public health hazard. Fires in-
volving pesticides are especially hazardous because of the possibility of poisoning from
vaporized chemicals added to the usual fire hazards of smoke inhalation and thermal burns.
Containers of pesticides rupture. Water and chemicals used to fight the fire spread con-
taminants over a wide area. Heat and air currents combine to vaporize pesticides and
cause them to enter the air. Fire fighters must take extraordinary precautions to avoid
breathing fumes and smoke from ignited storage areas and avoid body contact with water
and debris.
To summarize, the overriding theme put forth in the preceding pages has hopefully been one
of comon sense practice when dealing with pesticides or other hazardous chemicals. By
using either the direct or indirect approaches to safety, or a combination of the two, we
can expect to substantially reduce or eliminate the risks incurred when using toxic chemi-
cals such as pesticides.
References
1. Unpublished data furnished by State Services Branch technical assistance projects.
2. Wolfe, H. R. Protection of Workers from Pesticide Exposure. Proceedings of the Train-
ing Course “Pesticides and Public Health (Advanced)” January 18—20, 1971 , pp.117.
3. Maibach, H. I.; Feldmann, Robert; Milby, Tom; Serat, William. Proceedings of the
Symposium sulla prevenzione delle dermatosi professionali tenutosi, a Monte Porzio
Catone, Italy, 25-26 March 197G. pp. 61—64.

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167
PROPOSED FEDERAL PESTICIDE LEGISLATION
Emerson R. Baker
Soon after the Environmental Protection Agency was established (December 2, 1970) by Re-
organization Plan No. 3 of 1970 the Administration prepared the “Federal Environmental
Pesticide Control Act of 1971 ,“ which was introduced on February 10, 1971 , by Congress-
man Poage (Texas; Chairman, Committee on Agriculture) as House Bill No. 4152. An identical
bill was introduced on the same date in the Senate as S. 745 by Congressman Packwood
(Oregon).
The bill provides two changes in existing pesticide legislation:
First, it amends the Federal Insecticide, Fungicide, and Rodenticide Act to incor-
porate additional authorities relating to pesticide registration, such as factory inspec-
tion, registration of establishments, record keeping, stop sale or use orders, indemnities,
and classification of all pesticides as being either general use or restricted use.
Second, it enters a completely new area of Federal control over pesticides by re-
quiring all persons who wish to use a restricted pesticide to be certified by either the
State or Federal Government as being competent with respect to the use and handling of
such chemicals.
Extended hearings were held in the Committees on Agriculture of both Houses of Congress
and hearing reports prepared and published.
The House Committee on Agriculture made substantial changes in the original Administration
bill and a few additional changes of the Committee’s Bill (HR 10729) were made on the floor
of the House. The bill, as revised, was passed by the House on November 9, 1971. As of
1/1/72 the bill has not as yet been released from the Senate Committee on Agriculture
and Forestry, and further changes could be made.
The bill (H.R. 10729) itself is divided into four parts (sections). Part one is the title
(Federal Environmental Pesticide Control Act of 1971). Part two constitutes the major
part of the bill and is in the form of a cpmplete amendment to the Federal Insecticide,
Fungicide, and Rodenticide Act (of 1947). It, in fact, cancels the present FIFRA and re-
writes a new FIFRA containing 27 sections.
Selected excerpts from the Committee report* are of interest:
Section 1. Short title IFIFRA] and table of contents
Section 2. Definitions
Section 2 includes many of the definitions in the present FIFRA, with several
important changes.
A “certified pesticide applicator” is one certified by the State or Federal govern-
ment according to standards prescribed by the Administrator to use restricted use
pesticides.
A “private pesticide applicator” is a certified applicator who uses restricted use
pesticides only on his property, or on the property of another withoutcompensa-
tion.
*Comjttee on Agriculture: Report together with additional views to accompany H.R. 10729
[ Federal Environmental Pesticide Control Act of 1971]. H.R. Report No. 92—511, Sept 25,
1971.

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168
A “commercial pesticide applicator” is any certified applicator other than a pri-
vate applicator.
The definition of “misbranded” is amended to include requirements based on other
provisions of the Act. For example, labels must bear an establishment registration
number and use classification.
“Protect health and the environment” is defined, and includes the requirement to
take into account the public interest. “Substantial Adverse Effects on the Environ-
ment” contains the same requirement.
Section 3. Registration of pesticides
[ This section] requires that all pesticides in the channels of U.S. trade must be
registered with the Administrator. Under present law only those pesticides in
interstate commerce must be so registered. .
provides authority for the classification of pesticides and where applicable
the imposition of restrictions on their use.
‘a pesticide may be classified for general use, for restricted use, or both. In
the case of a pesticide registered for both general and restricted use the bill re-
quires that directions for each be separate and distinguishable.
a general use pesticide is one which the Administrator has determined will not
cause substantial adverse effects on the environment when applied in accordance with
its directions for use and warning or caution statements.
...arestricted use pesticide is one which the Administrator has determined could
cause substantial adverse effects on the environment without additional regulatory
restrictions...
when the pesticide presents a hazard to the applicator or other persons, it
must be used only by or under the supervision of a certified pesticide applicator
or be subject to other regulatory restrictions.
The foregoing classification and restriction constitute entry of Federal regulation
into a significantly unregulated area. General use pesticides will be regulated
as all pesticides under Federal jurisdiction are regulated at present...
Section 4. Use of restricted use pesticides; certified applicators
This section provides for Federal or State certification of pesticide applicators
according to standards prescribed by the Administrator. A State may certify appli-
cators if a plan submitted by the Governor is approved which designates a State
agency to administer the plan; assures legal ajithority, adequate funds, and quall-
fled personnel to execute the plan; provides for reports to the Administrator; and
contains applicator certification standards at least equal to those prescribed by
the Administrator...
Section 5. Experimental Use Permits
The Administrator may issue, under terms and conditions established by him, ex-
perimental use permits if an applicant needs such permit in order to accumulate
information necessary to register a pesticide. Such permit may be revoked if its
terms or conditions are violated or are inadequate to avoid substantial adverse
effects on the environment.
Section 6. Administrative review: suspension
Section 6 provides for the cancellation of a registered pesticide at the end of
each five year period unless the registrant requests that the registration be
continued. If a pesticide is otherwise cancelled for cause or the classification
is changed the registrant may make corrections or file objections and request a
public hearing. .
Language in the bill relating to scientific advice would maintain a role for sci-
entific advisory committees of the National Academy of Sciences equivalent to that
in the present provisions of FIFRA...

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169
Section 7. Registration of establishments
Products subject to the Act must be produced in establishments which are registered
with the Administrator. The producer who operates an establishment must inform the
Administrator within 30 days after it is registered of the types and amounts of
pesticides and devices which he is currently producing, produced during the past
year, or which he has sold or distributed during the past year.
Section 8. Books and records
The Administrator may prescribe regulations requiring producers to maintain such
records with respect to their operations and the products produced as are necessary
for enforcement of the Act. Such records required do not extend to financial data,
sales data other than shipment data, pricing data, personnel data, or research data
(other than data relating to registered pesticides or to a pesticide for which an
application for registration has been filed).
Section 9. Inspection of establishments
For purposes of enforcing the Act officers or employees duly designated by the
Administrator are authorized to enter any establishments at reasonable times to
inspect and obtain samples of any pesticides or devices, packaged, labeled, and
released for shipment, and samples of any containers or labeling for such products.
Section 10. Protection of trade secrets and other information
Section 10 of the Act provides that an applicant for the registration of a pesti-
cide may mark any part of the data submitted which in his opinion are trade secrets
or commercial or financial information and submit such material separately from
the other material required.
The Administrator would not make public any such information which in his judgment
contains or relates to trade secrets or comercial or financial information...
Section 11. Standards applicable to pesticide applicators
This section exempts private pestfcide applicators from any record keeping or re-
port filing regulations prescribed by the Administrator under the Act, and provides
that the Administrator shall establish separate certification standards for com-
mercial and private applicators.
Section 12. Unlawful acts
This section includes many prohibited acts frohi present law and is expanded to
cover intrastate acts and to prohibit violations of the provisions of the Act.
Among the new prohibitions is refusal to permit lawful inspection of an establish-
ment or sampling of a pesticide; advertisement of a restricted use product not
containing such classification; making available for use, or usinq, a restricted
use pesticide other than as provided under the Act or inconsistent with its
labeling; and violation of a “stop sale, use, or removal” order...
Section 13. Stop sale, use, removal, and seizure
Subsection (a) of this section authorizes the Administrator to issue a “stop sale,
use, or removal” order to any person possessing a device if he believes that the
pesticide or device is or will be sold in violation of the Act or if the registra-
tion has been suspended or is subject to a final cancellation order...
Section 14. Penalties
H.R. 10729 contains provisions for civil penalties. Such provisions are not in-
cluded in the existing FIFRA. Persons violating any provision of the Act would be
subject to a civil penalty of not more than $5,000 for each offense, except that a
private pesticide applicator would be subject to only a $1 ,000 penalty, and only
after receiving a written warning or citation for a prior violation. No civil
penalty could be assessed until the person charged has been given a notice and an
opportunity for a hearing in the county, parish or city of his residence...

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The reported bill also provides that any person who knowingly violates any provi-
sion of the Act shall be guilty of a misdemeanor and on conviction be fined not
more than $25,000 or imprisoned for not more than one year or both, except that
a private pesticide applicator could be fined not more than $1,000 or imprisoned
more than 30 days, or both.
Section 15. Indemnities
Subsection (aT provides that if the Administrator notified a registrant that he
has suspended the registration of a pesticide because such action is necessary to
prevent an imminent hazard and such registration is cancelled as a result of a
final determination that the use of such pesticide will create an imminent hazard,
any person owning any such pesticide before the suspension notice and who suffered
losses because of suspension and ensuing cancellation would be entitled to an indem-
nity payment.
...The amount...would be determined on the basis of the cost of the pesticide...
Section 16. Administrative review; judicial review
Except as otherwise provided by this section, chapter 5 of title 5 of the U.S. Code
relating to administrative procedure and chapter 7 of title 5 of the U.S. Code
relating to judicial review apply in respect of rules, rule making, orders, adjudi-
cation, licensing, sanctions, agency proceedings, and agency actions under the
Act...
The district courts of the U.S. are vested with jurisdiction to enforce and to
prevent and restrain violations of the Act...
Section 17. Imports and exports
Subsection (a) exempts from the provisions of the Act an exported pesticide or de-
vice which is in accordance with the specifications of the foreign purchaser.
Subsection (b) requires the Administrator to transmit through the State Department
to foreign governments and international agencies notice of pesticide registration
cancellations.
Subsection Cc) provides for the inspection of samples of imported pesticides and
devices provided by the Secretary of the Treasury to the Administrator, and for the
refusal of admission of a pesticide or device upon a finding by the Administrator
that it is in violation of the Act...
Subsection (d) requires the Administrator to participate in international efforts
to develop improved pesticide research and regu)ations...
Section 18. Exemption of Federal agencies
This section authorfzes the President to exempt a Federal agency from the provisions
of the Act if emergency conditions so require...
Section 19. Disposal and transportation
Sectionl9 provides that the Administrator of the Environmental Protection Agency
shall, after consultation with other interested Federal agencies, establish proce-
dures and regulations for the disposal or storage of excess amounts of such pesti-
cides. The Administrator would be also required to accept at convenient locations
for safe disposal a pesticide the registration of which has been cancelled under
section 6(c) if requested by the owner of the pesticide...
Section 20. Research and monitoring
This section authorizes the Administrator to use necessary means to undertake pesti-
cides research, giving priority to biologically integrated alternatives to chemicals
for pest control; to establish and implement a national plan for monitoring pesti-
cides, as well as undertake other monitoring activities necessitated by provisions
of the Act.

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171
Section 21. Solicitation of public coni ents
. ..The Administrator may solicit views of all interested parties and seek such
advice from “scientists,” farmers, farm organizations, and other qualified persons
as he deems proper.
Section 22. Delegation and cooperation
This section authorfzes the delegation of authorities vested in the Administrator
under the Act to his designees, and provides for cooperation by the Administrator
with other Federal agencies and with agencies of State and local governments in
carrying out the Act.
Section 23. State cooperation, aid, and training
This section authorizes the Administrator to enter into cooperative agreements
with States for purposes of enforcement of the Act, including training of personnel
and including grants for enforcement programs, and to assist States in establishing
applicator certification programs. Further, he may enter into contracts with
Federal and State agencies for the purpose of encouraging certified applicator
trai fling.
Section 24. Authority of States
This section specffies the authorities retained by the States under the Act.
Generally, the intent of the provision is to leave to the States the authority to
impose stricter regulation on pesticides use than that required under the Act.
Subsection (a) gives States the authority to regulate the sale or use of a pesti-
cide or device so long as such regulation does not permit sale or use prohibited
under the Act...
Subsection (b) preempts any State labeling or packaging requirements differing from
such requirements under the Act.
Subsection (c) provides the Administrator with authority to certify a State for the
purpose of registering pesticides formulated for intrastate distribution to meet
specific local needs. The purpose of this subsection is to give States the oppor-
tunity to meet expeditiously and with less cost and administrative burden on the
registrant the problem of registering for limited local use a pesticide needed to
treat sudden pest infestation.
Section 25. Authority of the Administrator
Subsection (a) of this section authorizes the Administrator to prescribe regula-
tions to carry out the Act.
Section 26. Severability
This standard severability section ...provides that.., the invalidity of one
“section” does not affect the validity of the others.
Section 27. Authorization for Appropriations
This sectfon authorizes appropriation of such sums as may be necessary to carry
out the provisions of the Act for fiscal years 1972, 1973, and 1974...
Part three of the bill amends the “...Federal Hazardous Substances Act, the Poison Pre-
vention Packaging Act, and the Federal Food, Drug, and Cosmetic Act to change the term
“economic poison” to the term “pesticide” in order to reflect the change in FIFRA.”
Part four of the bill establishes a time table for implementing the Act after oassage.
Of particular interest here are the following provisions:
...one year after...enactment...the Administrator shall have prescribed the
standards for the certification of pesticide applicators...

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172
...wlthin three years after...enactment...each State desiring to certify
pesticide applicators shall submit a State plan to the Administrator [ on
approval]...
...a period of four years from date of enactment shall be provided for
certification of pesticide applicators... [ and any requirement that a pesticide
can be used only by a certified applicator shall not take effect until four years
from enactment].

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173
PESTICIDE USE PATTERNS AND SAFETY ASPECTS
Dr. L. C. Gibbs
Pesticide use patterns, like our way of life, have changed significantly
over the years. Time was when our arsenal of pesticides consisted of soap,
sulfur and tobacco dust. Paris Green was added in 1860; lead arsenate in
1890. This was followed by calcium arsenate in 1919 when some 3 million
pounds were used for boll weevil control on cotton. These developments
alone point up the fact that we have been experiencing changing pesticide
use patterns for years. Needless to say, even more significant changes
can be expected in the years ahead as we anticipate population increases,
shorter work weeks, more leisure, and increased concern over environmental
quality. Coupled with future expectations, it is essential that we note
and consider other factors which have and will continue to exert a major
influence on our pesticide use patterns in the years ahead. Some of the
more important of these are: Public Sentiment, Legislation, Regulations,
Research, Technology, Agricultural Systems, Pest Resistance, Residue Toler-
ances, Lawsuits, Availability of New Pesticides, Pesticide Formulations,
Safety Requirements, and others.
Today everyone pretty well generally agrees that pest control is essential
for protecting man, plants and animals from diseases, discomforts or an-
noyances, and for insuring the production of an adequate and economical
supply of high quality food, feed and fiber. At the same time, many people
are demanding that many pesticides be banned. Irrespective of this, you
and I know that consumers would not be willing to accept more costly lower
quality foods. This poses some real questions which will require study
and a reevaluation of our sense of values, attitudes, and a willingness to
accept a middle ground position without sacrificing quality.
Documentation of the future need for pesticides is found in reports of -
The Ribicoff Committee (1964); National Academy of Science, Food and Feeds
(1968) and Persistent Pesticides (1969); the Mrak Commission (1969); and
elsewhere. These reports pointed up existing and potential problems, many
of which we are having to cope with today. Increasingly, our emphasis in
the years ahead will be placed on research, regulation, education and
operating programs which practice and encourage the use of the most effective
means of pest control and/or management that will cause the least potential
hazard to man, animals, plants, fish, wildlife and other components of the
environment. This means that many of the chemical uses producers have been
accustomed to in past years have already or soon will be lost. Cancel-
lation of certain uses of DDT, 2,4,5-T, Aidrin, Dieldrin, Mercurial fungi-
cides and other persistent pesticides are cases in point.

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174
Today, pest control in the United States is practiced in a setting of a popu-
lation growing in numbers, density and affluence and with an intensified mono-
cultural system of agriculture that is employing fewer and fewer persons. In
the early years, a farmer produced only enough food for his family and about
three others; today, he produces enough for his family and about 45 others.
In order to grasp the full significance of some of the developments that have
taken place which have been instrumental in effecting changes in our pesticide
use patterns, we need only to recall some of the major changes that have taken
place in agriculture. Perhaps the first one we should note is that in the
early history of agriculture, farming was diversified and our pest control
knowledge and chemicals were limited to ay the least. Even in the early 40’s,
we could still count our pest control materials on our fingers and the commonly
available materials included items such as lime sulfur, Paris green, lead
arsenate, nicotine sulfate, Rotenone and a few others. In contrast today, our
pest control arsenal consists of about 250-300 agricultural chemicals available
in some 35,000 registered products. Needless to say, almost everything has
changed. Foremost among the factors which have been influencing changes in
pesticide use patterns has been the shift toward development of an intensive
monoculturistic system of agriculture. This system, for the sake of economy,
has resulted in the concentration and culture of large blocks or acreages
of a single or successions of the same crop. This alone has been conducive to
a build-up of certain pests which required more pesticide use and in some
cases resulted in the development of resistance to certain pesticides within
some insect species. Increased production costs resulting from labor shortages,
increased labor costs, etc. have also been conducive to mechanization and this
in turn has fostered increased plant populations which further contributes to
increased insect and disease problems. So you see, the circle goes round and
round and never stops or stands still. Other factors include the passage of
more stringent regulations and laws governing the registration, transportation,
sale and use of pesticides, lowered residue tolerances, and the development of
the carbainate and systemic type pesticides. One other factor which I have so
far failed to mention specifically is the advances made in our analytical equip-
ment and technology. Each factor or combination of factors in turn affects use
patterns one way or another and the full impact or change can seldom be fully
determined.because of the complexity and interaction involved.
• Any discussion of changing pesticide patterns would be remiss without some
mention of use statistics and recent legislative and regulatory developments.
First let’s look at some aspects of use statistics since this is undoubtedly
the area which has contributed most to some of our problems. Use, likewise,
has without question been the paramount factor responsible for the tightened
legislative and regulatory actions which have been effected in the last few
years. In looking at use statistics, I think that it is important that we look
at the volume used and note the use trends developed within the three major
classes of pesticides and within even a single class. The following tables,
which are more or less self-explanatory, show what the use patterns and trends
have been over the years for pesticides as a whole and for some within a group
or class. See Table 1 for statistics on pesticide sales volume for fungicides,
herbicides and insecticides. Table 2 is illustrative of trends and use patterns
developed for the organochlorine type insecticides.

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Table 1. Sales of organic pesticides by primary chemical manufacturers according
to type of usage, 1963-1970.
175
Type of Usage
:
:Amount
1963 : 1964 : 1965 : 1966
Tof Total: Amount Tof Total: Amount Tof Total: Amount rof Total
Fungicides
Herbicides
Insecticides
TOTAL.
93,265
122,872
435,334
651,411
(Volume of sales in 1 000 pounds)
14.3 : 9 ,5S6 13.a : IO ,342 13.9 : 118,397 14.4
18.9 : 152,027 21.9 : 182,869 23.9 : 221,502 26.9
66.8 : 444,772 64.3 : 474,694 62.2 : 482,357 58.7
: 692,355 : 763,905 : 822,256
,
‘Type of Usage
:
:Amount
1967 1968 1969 1970
T’of Total: Amount Tof Total: Amount ‘Tof Total: Amount Tof Total
‘Fungicides
Herbicides
Insecticides
TOTAL
120,413
287,582
489 368
891,363
(Volume of sales in 1,000 pounds)
13.4 : 129,961 13.5 : 121,418 13.4 : 128,859 14.6
32.1 : 318,554 33.2 : 311,157 33.5 308,112 35.0
54.5 : 511,116 53.3 : 493,088 53.1 : 443,943 50.4
: 959,631 : 925,663 : 870,314
Table 2. Organochiorine insecticides: Producers’ domestic
disappearance of selected kinds by crop year,
t United States, 1955—1970.
:
Crap Year 1/ :
:
Aidrin-
toxaphene 2/
group
:
: our.
:
:
:
:
BIC
:
:
Total
:
1955
1956 :
Volume in
1,000 pounds
124,000
146,020
54,400 61,800
61,570 : 75,000
,
;
:
7,800
9,450
:
1957 :
1958 :
1959 :
1960 :
1961 :
1962 :
1963 :
1964 :
1965 :
1966 :
1967 :
1968 :
1969 :
1970 :
52,500
78,834
73,331
75,766
78,260
82,125
79,275
83,161
80,568
86,646
86,289
38,710
89,721
62,282
: 71,000
: 66,700
: 78,682
: 70,146
: 64,068
67,245
: 61,165
: 50,542
: 52,986
: 46,672
: 40,257
32,753
: 30,256
: 25,457
:
:
:
:
:
:
:
:
:
:
:
:
:
:
6,600
5,500
4,276
5,111
4,577
2,404
1,299
3/
Ni
T/
T/
T/
Ti
TI
:
:
:
:
:
:
:
:
:
:
:
:
:
:
130,100
151,034
156,289
151,023
146,905
151,774
141,739
133,703
133,554
133,318
126,546
71,463
129,977
87,739
4/
Ti
TI
Ti
Ti
Ni
/
Ends September 30.
2/ Includes aidrin, chiordane, dieldrin , endrin, heptachior, Strobane and
— toxaphene.
3/ Not published separately to avoid disclosure, but probably less than
— in 1963.
4/ Includes only the aldrin-tozaphene group and DOT.
5/ Calendar year data.

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176
The use of persistent pesticides underwent more intensive discussion in 1969
than ever before. Although pesticides have contributed tremendously to pre-
venting human disease and to increasing the production of food and fiber, mount-
ing evidence indicated the need for concern about unintended effects on the
environment, including injury to the health of man and livestock. Associated
with the benefits from the use of pesticides are the risks of injury; and these
risks are greater from the use of persistent chemicals. Restrictions have now
been placed on the latter with special emphasis on DDT. Coupled with this have
been numerous State legislative actions which relate to pesticide use, sale,
record-keeping, applicator licensing, development of restricted use categories,
etc. In this respect it is of interest to note that as of November 1970, 36
States had enacted pesticide applicator licensing laws. Other significant
developments include complete restriction on the use of DDT in a number of
States and the development of lists of chemicals limited to restrictive or
permit uses.
The major persistent pesticides are commonly known as “organochlorine” compounds
(“chlorinated hydrocarbons” or “polychiors”). They include aldrin, benzene
hexachloride, chlordane, DDD, DDT, dieldrin, endrin, heptachior, lindane, toxa-
phene, and certain others. Compounds containing arsenic, copper, lead, and
mercury are also persistent.
In recent years, DDT has become a prime target of concern. Its usage began
earlier and has been more widespread than that of other major persistent pesti-
cides. For well over two decades, DDT has been the most generally effective
and most widely used pesticide worldwide. It is best known for practically
wiping out malaria in the United States and over large areas elsewhere. It has
been a valuable tool in combating cholera, typhus, Rocky Mountain spotted fever,
and encephalitis. Uninhabitable areas have been made more habitable and life
has been made more comfortable for many people. DDT also has worked wonders
for farmers. Its use has controlled many major insect pests, notably those
those troublesome to cotton, vegetables, and fruit.
Few food-producing areas are free of DDT contamination. There has been awareness
of this for some years. The President’s Science Advisory Committee in 1963 called
attention to low-level contamination of the environment with DDT. As long as
two decades ago, DDT residues in milk caused restriction to be placed on its use
for controlling flies and other insects on dairy cattle.
Use of certain other organochiorines on forage grazed by dairy cattle was re-
stricted for the same reason; namely, residues in milk.
Use of DDT in the United States during crop year 1970 was only 33 percent as much
as in 1959. Its use peaked in 1959 at more than 78 million pounds but declined
to less than 33 million in 1968, 31 million in 1969 and 26 million in 1970.
Current plans, barring cancellation, call for reducing DDT usage on cotton sig-
nificantly in the next few years through pest management programs involving
scouting, use of biological and cultural controls, and other other measures.
Much of the contamination from persistent pesticides may have resulted from
excessive use. Although environmental contamination from past usage will

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177
continue for a period of years in lessening amounts, further reduction in usage
and careful application of all pesticides can be expected to substantially lessen
this type of pollution of the environment.
Progress with less hazardous controls . Research has already developed chemicals
suitable for use to control many target pests and which are less persistent and
more specific than the organochlorine insecticides. Readily degradable chemicals
and biological, physical, and cultural controls as an integrated assault offer
areas for research into possible answers to many uses of persistent pesticides.
The emphasis on newer weapons includes the study and development of viruses
causing insect diseases, sterilization of adult insects to disrupt their renro-
ductive cycle, synthesis of natural insect attractants or effective substitutes
as lures, ultraviolet light and ultrasonic sound as control agents, hormones that
interfere with normal insect growth, and the manipulation of genes. Further
research is being stimulated in the breeding and utilization of domestic and
imported predatory and parasitic insects, long used as essential biological
aids in the control of a number of insect pests. Application of new technology
and increased acceptance and adoption of pest management principles and practices
should enable us to reduce pesticide use significantly. On cotton, for example,
if projected plans materialize, it is anticipated that a reduction in the use
of DDT from 10 million pounds in 1972 to about 2 million pounds in 1975 can be
effected. To say the least, the future will be challenging and perhans wrought
with some frustrations.
So far, I haven’t said much about safety as it relates to the use of pesticides.
Our safety records are good, but we hope they can be improved in the years ahead.
Pending legislation, stricter enforcement of existing laws and regulations, and
the Occupational Health and Safety Act of 1970 should be of material assistance
in helping decrease accidents and fatalities associated with pesticides. Plans
also call for stepping up educational work with audiences such as dealers, appli-
cators, and farm workers in the years ahead. Some of these audiences are likely
to be more receptive because of the legal implications, possible licensing
requirements, record-keeping requirements, use restrictions, and other aspects.
Future emphasis on pesticide safety will be directed to supervisors and workers
who are involved in operations related to the use, record-keeping, storage,
handling, transporting, mixing, and disposal of pesticides. Mother area which
will be given added attention is that of selection and use of safety equipment,
clothing, sanitation, and personal hygiene. Implementation of work in this
latter area is expected to be effected through cooperative efforts on the part
of the medical profession, public health officials, industry and educational
groups.

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REFERENCES
1. The President’s Science Advisory Committee, 1963. Use of Pesticides.
U.S. Government Printing Office, Washington, D.C.
2. Committee on Persistent Pesticides, 1969. Division of Biology and Agriculture,
National Research Council. Report to the U.S. Department of Agriculture.
Washington, D.C.
3. U.S. Department of Agriculture, 1969. Secretary’s Memorandum No. 1666,
USDA Policy on Pesticides.
4. The Pesticide Review--l970. ASCS, U.S. Department of Agriculture, Washington,
D.C.
5. Summary of Registered Agricultural Pesticide Chemical Uses, Third Edition,
Volumes I, II, and 111. Pesticide Regulation Division, CARS, U.S. Department
of Agriculture) Environmental Protection Agency, Washington, D.C.

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179
INTRODUCTION TO THE CHEMICAL ANALYSIS OF PESTICIDES
A. Curley
In pesticide analysis at the trace level the proper collection, preservation and
storage of samples are extremely important. To insure meaningful analysis, the
samples should be preserved and shipped to the chemist without degradation and con-
tamination with impurities that might interfere during analysis. For tissues, wide
mouth glass bottles with screw caps containing foil liners are recommended. Class
vials with foil-lined screw caps are recommended for blood samples. Tissues should
be deep frozen (-12 to -18°C) until time of analysis or held at normal refrigeration
temperature if the analysis is immediate or within 24 hours.
Since most samples in pesticides health effects research are animal tissues and
excretia, this discussion will be limited to those methods used to assay samples for
pesticides as the parent compound and its metabolites. The epidemiological investi-
gation will usually provide the analyst with some information about the possible con-
taminant. Based on the available samples, he can then make a decision on the be-
havior of the chemical in various methods and then make the proper selection of the
method that will be used for analysis.
For fatty samples, the multiresidue extraction and cleanup method involves extraction
of fats and pesticides with petroleum ether, acetonitrile partitioning, dilution of
acetonitrile with water and extraction into petroleum ether, florisil column cleanup,
partition chromatography and any supplemental cleanup (modified Mills, Onley and
Caither procedure). Non-fatty samples may be extracted with acetonitrile or water-
acetonitrile. The acetonitrile is diluted with water and the pesticide residues are
extracted into petroleum ether followed by chromatography on a Florisil column
eluting with mixed petroleum and ethyl ethers.
Specific methods for the analysis of chlorinated pesticides are the modified Dale,
et. al. hexane extraction procedure for blood and the modified method that combines
portions of methods by Rivers and by Cranmer and Freal for the determination of
pentachlorophenol in blood and urine by extraction of the acidified sample in benzen ,
methylation with diazomethane and subsequent analysis by electron-capture gas-liquid
chromatography either on 47 SE3O/6% QF-l or 57 OV-210. Other chlorinated monophenols,
biphenols and chiorophenoxy herbicides can also be analyzed by similar methylation
methods.
The pesticide analyst is sometimes required to make assays pertaining to organo-
phosphorus pesticides. In metabolism, oxidative reactions usually result in detoxi-
fication of the compound but with organophosphates oxidation can lead to a metabolite
that is more toxic than the parent compound. Thus, parathion is converted to
paraoxon and systox to sulfoxide and sulfone. Hydrolysis is another detoxification
process. Biochemically active compounds or those that are active as a result of
metabolism are hydrolyzed by breaking any P-OR or P-SR bond that destroys the actual
or potential activity. Multiple detection methods have been devised to analyze
(identify and quantitate) the phosphate residue as the parent compound or an altered
or metabolic product. Specific methods have been devised to detect the phosphate
residue in urine as hydrolysis products - phenols from parathion and salts of
dimethyl or diethyl phosphates, thio and dithiophosphates. Sensitive procedures
have been devised to measure the cholinesterase activity of these compounds.

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Gas-liquid chromatography is usually used for quantitative determinations of chlori-
nated, phosphorous and nitrogen-containing pesticides in residue analysis. The
detection system utilized depends on the structure of the compound or the function-
ality present in the molecules. This system can be either electron-capture, electro-
lytic-conductometric, microcuolometric, thermionic, flame photometric or thermal
conductometric. Individual pesticides may be detected by one or more detectors but
they may not be recovered through the recommended extraction and cleanup procedures
as previously discussed. This technique utilizing the most sensitive detection
system, i.e., electron-capture, can identify and measure subnanogram amounts or a
few parts per billion of a compound. The basic instrument consists of an injection
port,column packed with a support coated material, a carrier gas supply and regu-
lators, a detector and an electrometer and recorder to amplify and record the de-
tector signal, including associated equipment such as temperature regulators. Present-
ly, there is a large variety of commercial sources for various gas chromatographs.
Good chromatograms with low signal-to-noise ratios and stable baselines are impor-
tant for meaningful interpretation of the curves.
Column selection, like detectors, must be based on the class or functionality of the
individual pesticides. Glass columns are recommended for most pesticide analysis.
Pre-coated packing materials can be bought commercially; however, the liquid phases
and solid supports can be bought separately and the columns prepared by the labora-
tory staff with excellent efficiency. Columns are made ready for use by heat curing,
silylation and pesticide conditioning. Column efficiency is usually referred to in
terms of the number of theoretical plates because of the similarity of a gas chromato-
graphic column to a distillation column. The efficiency f the column can be ob-
tained from the chrotnatogram by the expression n = l6( )
Where n = number of theoretical plates of a column towards a particular compound.
rt = retention time, retention volume, or corrected retention volume of
the same compound.
w = peak width corresponding to the same compound.
Once the number of theoretical plates, n, is known the height equivalent to a theo-
retical plate, HETP, or H can be calculated by:
h=
Where n = number of theoretical plates
L = length of column
Columns can be used over long periods of time if properly maintained.
Although non-specific but highly sensitive, the electron-capture detector is the
most used in pesticide analysis. This detector is an ionization detector consisting
of a cell with polarized electrodes electrically insulated from each other. The
radioactive source, usually tritium - a•weak beta emitter, produces the ionization
of the compound. For a hydrogen flame detector it is the flame itself. The effluent
gas from the GLC column passes through the cell to monitor its electrical conduc-
tivity. At equilibrium, the conductivity is a constant. Compounds in the effluent
carrier gas to which the detector responds changes the conductivity. The changes
in conductivity are measured continuously throughout the chromatographic analysis.
A d.c polarizing voltage is usually supplied to the detector, whether electron-
capture or flame. If the e.c. detector is used it is important to determine the
optimum operating voltage by establishing a background signal profile. As radio-
activity decreases from contamination of the detector periodic measurements should
be made to provide up-to-date information on the detector performance. For quanti-
tative analysis, the analyst should always be certain that the compound concentration
is within the linear range of the detector.

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The thermal conductivity, microcoulometric and electrolytic conductometric detectors
are non-ionizing detectors. The first two are much less sensitive than the latter.
These are relatively specific and can be used for confirmation purposes. The flame
photometric and thermionic detectors are used as specific detectors for phosphorus-
containing compounds. Sulfur-containing compounds are also determined with the
flame phorornetric detector.
Thin-layer chromatography is often used for qualitative confirmation of pesticide
assays by gas-liquid chromatography; however, the technique can also be used to make
semi-quantitative determinations. Aluminum oxide plates (8” x8”, 4” x 4” or 1” x 3”)
are generally used for chlorinated organic residues. The solvent development systems
and visualization techniques are as follows:
Development System Visualization
n-heptane Spray with AgNO 3 and 2-phenoxyethanol.
2°!. Acetone in n-heptane Expose to UV.
n-heptane Incorporate AgNO 3 in layer. Expose
20/. Acetone in n-heptane to liv.
n-heptane Spray with AgNO 3 and 2-phenoxyethanol.
1% Acetone in n-heptane Expose to UV.
2,2,4-trimethylpentane with
25% DMF
n-heptane Incorporate AgNO 3 , dichlorofluores-
2% Acetone in n-heptane cein and hydroquinone in layer. Ex-
pose to UV.
The Rf values represent the migration distance of the pesticide compared to a refer-
ence compound. These Rf values for various solvent systems can be effectively used
to indicate whether pesticides found by GLC will be separated on the plate and to
assist with the identification of the pesticide.
Ionic chlorinated organic residues can be determined by TLC but the developing
solvent system is generally changed to a more polar system such as n-hexane saturated
with acetonitrile. Organophosphate esters (thio phosphates, non thiophosphates) can
be determined by the methods of Kovacs ancj Watts. The methods of Kovacs and Watts
are as follows:
Kovacs Development solvent Chromogenic agent
Methy lcyc lohexane tetrabromophenolphtha 1cm
(15%-20% DMF in ethyl ether ethyl ester, AgNO 3 , citric acid.
dipping solvent)
Watts 20% methylene chloride in 4-(p-nitrobenzyl) pyridine in
cyc lohexane acetone.
10% tetraethylene pentamine in
acetone.
The methods of Mitchell and Mills present paper chrotnatographic techniques for
chlorinated organic residues.
Apart from extraction p-value determinations TLC and paper chromatography, spectro-
scopic methods are currently being used for most confirmatory tests to substantiate
GLC analysis.

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The most sensitive of these methods is combined gas chromatography mass spectrometry.
The instrument consists of a gas chroniatograph interfaced through a molecule separator
with a mass spectrometer. The molecule separator effects a separation of the organic
effluent from the carrier gas. Presently, quadruple instruments and chemical ioni-
zation sources are of particular interest. Mass spectrometers have been computerized
for ease of data reduction and interpretation. Using a low to medium resolution
instrument, unity mass can be obtained with accuracy. High resolution instruments
give more accurate mass measurements to millimass units. In either case one gets an
accurate estimation of the molecular weight of the compound. If enough sample is
available infra-red and ultra-violet analysis can be made to determine the functional
groups present in the molecule. These data together with nuclear magnitic resonance
spectra for the proton determinations provide a great deal of structural information
about a substance that ultimately aids the analyst in making a positive identifi-
cation of the compound.
The principles involved in IR, UV, and NNR spectroscopy including the mechanics of
measurement, applications and tables of data on characteristic absorption of function-
al groups and correlations of hydrogen bound to carbon can be found in standard
texts and monographs. One suggested monograph is “Application of Absorption Spectro-
scopy of Organic Compounds” by Dyer.
For pesticides containing heavy metals such as the organomercurials, arsenicals and
thallates, atomic absorption spectrophotometry has gained widespread use. This
technique usually involves the destruction of the sample by wet ashing, chelation
and extraction into a suitable organic solvent and analysis by flame photometry.
More recently flameless techniques have been developed to analyze mercury. This
laboratory is working on a flameless technique for arsenic determinations. These
flameless techniques involve suitable reduction of the sample and the generation of
a vapor that is passed into a tube that is placed in line with a beam of monochromatic
light. If a flame is used, the light is also passed through it, resulting in re-
duction of its intensity by a portion of light. Since the absorption is proportional
to the concentration of neutral atoms in the flame, quantitative determination of
the concentration of the metallic element in the original solution can be found by
measurement of the absorption. The Beer-Lainbert law which states that the intensity
of the transmitted light is affected by the concentration of the absorbing species
and the thickness or length of the absorbing medium is obeyed in atomic absorption
spectrometry. This law may be expressed as:
log = -K lc
or log I = log 10 - K lc
where 10 = initial intensity
I = reduced intensity
extinction coefficient
1 = length of absorbing medium or thickness of flame in AAS
C = concentration
Such topics as the function of the flame, flame temperatures, suggested gases for
certain types of burners and specific metals, burner operation, multi-passing optics,
recommended hollow cathode lamps, the monochromotor ( grating choice and atomic line
choice, i.e. primary or secondary) recognition and elimination of interference and
flame emission are discussed in detail in technical bulletins or manuals from the
manufacturer or in textbooks and the Atomic Absorption Newsletter as published by
the Perkin Elmer Corporation.

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The elements of primary toxicological interest are mercury (Hg), lead (Pb), thallium
(Ti) and arsenic (As). These elements can be determined in the same sample using
the chelation - extraction flame technique. Mercury and arsenic can be analyzed
by the above or the reduction, flameless technique.
In sunmiary, this brief discussion has presented some aspects of the principles,
techniques and applications of those methods and instrumentation that are presently
being used for the chemical analysis of pesticides in tissues and excretia of ex-
perimental animals and humans. These methods, either modified or in their present
form, can also be used for certain environmental samples.
Re ferences
1. Pesticide Analytical Manual. Vol. I USDHEW, FDA, Washington, D.C. Jan. 6, 1968.
2. Manual of Analytical Methods - Analysis of Pesticide Residues in Human and
Environmental Samples. EPA, Perrine Research Laboratories, Perrine, Florida,
January 1971.
3. Dale, W.E., Curley, A., Cueto, C. Life Sci. 5, 47 (1966).
4. Mills, P.A., Onley, J.H., and Gaither, R.A. J.A.O.A.C. 46, 186 (1963).
5. Lovelock, J.E. and Lipsky, S.R. J. Am. Chem. Soc. 82, 431 (1960).
6. Lovelock, J.E. Nature 189, 729 (1961).
7. Cranmer, M. and Freal, J. Life Sci. 9, part II, 121 (1970).
8. Cranmer, H. and Freal, J.F. Bull. Environ. Contamin. & Tox. 9, part II, 121
(1970).
9. Bowman, M.C. and Beroza, M. Anal. Chem. 40, 1448 (1968).
10. Shafik, M.T. and Enos, H.F. J. Agr. & Food Chem. 17(6), 1186 (1969).
11. Shafik, M.T., Bradbury, D., Biros, F.J. and Enos, H.F. J. Agr. & Food Chem.
18(6), (1970).
12. Stahl, E. Thin-layer chromatography - A Laboratory Handbook. New York,
Springer-Verlag: 1969.
13. Kovacs, M.F., Jr. J.A.O.A.C. 47, 1097 (1964), J.A.O.A.C. 50, 213 (1967);
Getz, M.E. J.A.O.A.C. 45, 393 (1962); Wood, T. Nature 176, 175 (1955);
Watts, R.R. J.A.O.A.C. 48, 1161 (1965).
14. Mitchell, L.C. J.A.O.A.C. 40, 999 (1957).
15. Mills, P.A. J.A.O.A.C. 44, 171 (1961).
16. Dyer, John R. Applications of Absorption Spectroscopy of Organic Molecules.
Englewood Cliffs, New Jersey: Prentice-Hall, Inc. 1965.
17. Biemann, K. Mass Spectrometry - Organic Chemical Applications. New York:
McGraw - Hill Book Co., 1962.
18. Atomic Absorption Newsletter. Perkin-Elmer Corporation, Norwalk, Conn.

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19. Hatch, W.R. and Ott, W.L. Anal. Chem. 40, 2085 (1968).
20. Kahn, H.L. Atomic Absorption Newsletter j Q (2), 58 (1971).
21. Littlewood, A.B. Gas Chromatography Principles, Techniques and Applications.
New York: Academic Press, 1962.
22. McNair, N.M. and Bonelli, E.J. Basic Gas Chromatography. Berkeley, Calif.:
Consolidated Printers, 4th Printing, 1968. Available only through Varian
Aerograph, 2700 Mitchell Drive, Walnut Creek, Calif. 94598.

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