I ENVIRONMENTAL PROTECTION AGENCY
? OFFICE OF WATER PROGRAMS
THE MOVEMENT AND IMPACT OF PESTICIDES USED FOR VECTOR CONTROL
ON THE AQUATIC ENVIRONMENT IN THE NORTHEAST
-------
PESTICIDE STUDY SERIES - 9
THE MOVEMENT AND IMPACT OF
PESTICIDES USED FOR VECTOR
CONTROL ON THE AQUATIC ENVIRONMENT
IN THE NORTHEASTERN UNITED STATES
This study is the result of Contract No. 68-01-0129
awarded by the OWP, as part of the Pesticides Study
(Section 5 (1)(2) P.L. 91-224) to Cornell Aeronautical
Laboratory, Inc.
The EPA Project Officers were:
Charles D. Reese, Agronomist
David L. Becker, Chemical Engineer
ENVIRONMENTAL PROTECTION AGENCY
Office of Water Programs
Applied Technology Division
Rural Wastes Branch
TS-00-72-09
July 1972
For sale by the Superintendent of Documents, U.S. Government Printing OHicc
Washington, IXC. 20402 - Price $1.75
-------
EPA Review Notice
This report has been reviewed by the Office of Water
Programs of the Environmental Protection Agency and
approved for publication. Approval does not signify
that the contents necessarily reflect the views and
policies of the Environmental Protection Agency, or
does mention of trade names or commercial products
constitute endorsement or recommendation for use.
-------
ACKNOWLEDGEMENTS
This report is a result of only six months of study and research, and its
completion required significant cooperation from a large number of people.
Although it is not possible to recognize every contribution, the project
director thanks the following for their valuable assistance:
Mr. Edward Cooper
Allied Chemical Corp.
Wilmington, Delaware
Mr. Carl Amalia
Amalia Tree Surgeons
Manchester, Massachusetts
Mr. Richard Ferrara
Hartney Spray Corp.
Norwood, Massachusetts
Dr. Gordon Nielsen
University of Vermont
Burlington, Vermont
Dr. Richard Magee
American Cyanamid Co.
Princeton, New Jersey
Mr. Paul Morse
R. F. Morse and Co.
Wareham, Massachusetts
Mr. Julius Elston, Chief
Mosquito Control Section
Connecticut State Dept. of Health
Madison, Connecticut
University of Massachusetts
Cranberry Experiment Station, Wareham, Mass.
Dr. Chester Cross
Dr. Karl H. Deubert
Mr. I. E. Demoranville
Cape Cod Extension Office, Barnstable, Mass.
Mr. Oscar S. Johnson
Mr. Arnold C. Lane
Mr. Durwood French
Suburban Experiment Station, Waltham, Mass.
Dr. John Naegele
State Pesticide Control Board
Durham, New Hampshire
Dr. James Bowman
University of New Hampshire
Durham, New Hampshire
ii
-------
U.S. DEPARTMENT OF AGRICULTURE
Agricultural Research Service
Dr. Irwin Gilbert Gainesville, Florida
Dr. Claude Sr:hmiat Beltsville, Maryland
Dr. Warren Shaw Beltsville, Maryland
Mr. John Fluno Beltsville, Maryland
Soil Conservation Service
Mr. August Reese Middleboro, Massachusetts
Mr. Henry Ritzer Middleboro, Massachusetts
Mr. J. Louis Robert! Hyannis, Massachusetts
COMMONWEALTH OF MASSACHUSETTS
DEPARTMENT OF AGRICULTURE
State Reclamation Board
Mi. Edward Wright.
Mr. John McColgan
Mr. Clarence Tourville
Mr. Harold Rose
Cepe Cod Mosquito Control Project
Mr. Oscar W. Doane, Jr.
Mr. Paul Velkenier
Professor W. J. Wall, Jr.
East Middlesex Mosquito Control Project
Mr. Robert Armstrong
Department of Natural Resources
Division of Marine Fisheries
Sandwich Laboratories
Department of Public Health
Pesticide Board
Lewis Wells
Mr. Donald Mairs Mr, Rudolph D'Andrea
Maine State Pesticide Board State Department of Natural' Resources
Augusta, Maine Providence, Rhode Island
iii
-------
I. INTRODUCTION
TABLF. OF CONTENTS
PAGE
SUMMARY
1
II. FINDINGS AND NEED FOR ACTION 3
A. INVENTORY OF Ut^E£ 3
B. METHODS OF APPLICATION 8
C. ROUTE INTO WATER 10
D. IMPACT ON THE ENVIRONMENT 13
E. DEGRADATION AND METABOLISM ^5
F. LAWS AND REGULATIONS 20
G. ALTERNATIVE METHODS OF CONTROI, 22
FART TWO
I. STATEMENT OF WORK 1
II. NATURE AND EXTENT OF VECTOR PROBLEMS 2
A. DISEASE VECTORS 2
B. NUISANCE VECTORS 3
III. PESTICIDES USED FOR VECTOR CONTROL 4
A KINDS OF MATERIALS USED 4
B. SPECIFIC MATERIALS USED 5
C. QUANTITIES USED 6
D. PESTICIDES USED ON CAPE COD 11
E. PESTICIDES USED IN TWO SALT MARSHES 11
IV. METHODS OF APPLICATION AND TYPE OF MATERIALS 15
A. ADULTICIDING 15
B. LARVICIDING 16
C. FORMULATIONS OF MATERIALS USED 17
D. FORMULATIONS OF PESTICIDES USED ON CAPE COD 18
iv
-------
TABLE OF CONTENTS (Continued)
PAGE
V. ROUTE OF PESTICIDES INTO THE WATER ENVIRONMENT 20
A. INTRODUCTION 20
3. HANDLING AND TRANSFER ^ETHODS 21
C. FINAL APPLICATION AND CONTAINER DISPOSAL 24
D. INTENTIONAL APPLICATIONS 28
VI. IMPACT ON ENVIRONMENT 33
A. DESCRIPTION OF STUDY AP.EA 33
B. TOXICITY OF PESTICIDES 55
C. IMPACT OF VECTORICIDES ON THE ESTUARINfi ENVIRONMENT 67
D. IMPACT OF VECTORICIDES ON MAN 79
VII. DEGRADATION OF PESTICIDES AND METABOLITES IN THE WATER 93
ENVIRONMENT
A. INTRODUCTION 93
B. DECOMPOSITION MECHANISMS 96
C. RESIDUAL LEVELS OF INSECTICIDES, 108
D. GLOSSARY OF TERMS 123
VIII. LAWS AND REGULATIONS 132
A. FEDERAL REGULATION OF PESTICIDES 132
B. MASSACHUSETTS REGULATION OF PESTICIDES 135
C. OTHER NEW ENGLAND SPATES' REGULATION OF PESTICIDES 167
D. DEGREE OF ENVIRONMENTAL PROTECTION PROVIDED BY EXISTING 175
LAWS, REGULATIONS AND PROCEDURES
E. STRENGTHENING THE ENVIRONMENTAL PROTECTION AFFORDED BY 181
EXISTING LAWS, REGULATIONS, AND PRACTICES
-------
TABLE OF CONTENTS (Continued)
PAGE
-1 QO
IX. ALTERNATIVE METHODS OF CONTROL
A. LIFE HISTORY OF MOSQUITOES AND ITS EFFECT ON CONTROL 189
B. NATURAL ENEMIES OF THE AQUATIC STAGES OF THE MOSQUITO 19?
1 Qii
C. NATURAL ENEMIES OF THE ADULT MOSQUITO iy*
D. NATURAL PARASITES 194
E. EMPLOYMENT OF NATURAL ENEMIES FOR MOSQUITO CONTROL 194
F. CONTROL BY ALTERATION OF LIFE CYCLE 196
G. MECHANICAL METHODS OF MOSQUITO CONTROL 198
H. PESTICIDE USES CONSIDERED ESSENTIAL FOR ACCEPTABLE 198
CONTROL
vi
-------
ENVIRONMENTAL EFFECTS OF PESTICIDES USED FOR VECTOR
CONTROL IN THE NORTHEASTERN UNITED STATES
In the northeastern United States the mosquito
abatement programs are conducted for the vector control of
Eastern equine encephalitis, to reduce the nuisance problem
caused by mosquitoes, and to enhance recreation areas.
Typically, these programs consist of the application of
pesticides (vectoricides) and the drainage of stagnant
water. Unfortunately, pesticide applications are often made
without proper safeguards to prevent damage to the aquatic
environment.
Almost all aquatic organisms spend at least part of
their life cycle in the salt marsh and estuarine areas or
depend on a steady flow of nutrients from these areas where
migratory birds and waterfowl are regular visitors. Damage
to aquatic environment is of concern to the commercial
fishing industry and to those who enjoy the aesthetic values
of recreational areas in the region.
This report summarizes a case study concerning an in-
depth investigation of a specific vectoricide use situation
S-l
-------
documenting the kinds and quantities used, their route from
the point of initial application into the water environment,
their ultimate effect on the ecosystem, and the laws and
regulations which affect their use. Cape cod was chosen for
this study because it is an important commercial fishing
center and the most popular seashore recreational area in
the Northeast. It has a long history of mosquito abatement
programs whicn formerly included the use of persistent
vectoricides but in recent years has been limited to easily
degradable light mineral oil. With this treatment history,
the area affords an opportunity to study the long-term
effects of vectoricides without interference from effects
caused by recent applications.
The Bass Hole Marsh in Dennis and the Herring River
Marsh in Harwich were selected for intensive study to
compare the effects of treatment programs on the north and
south shores of Cape Cod. A literature search was conducted
and interviews were held with concerned officials,
businessmen and private citizens throughout New England.
Additional field work was undertaken in the two marshes to
observe the effects of vectoricides on the aquatic
environment, and soil and water samples were analyzed to
check the general level of vectoricide residues.
S-2
-------
Inventory of Usgs
In New Enqland, malathion was the principal chemical
compound used in 1970. It was used as both a mosquito
larvicide and adulticide, and it accounted for nearly 60% of
the total quantity reportedly used in the various states, as
shown in Table 1. Althouqh pesticide consumption records
are qenerally inadequate to permit precise estimates of use
patterns in most states (New Hampshire is the lone
exception), it is qenerally believed that the use of
malathion has increased at a rate which matches decreases in
the use of DDT and other persistent chlorinated
hydrocarbons. Methoxychlor, which is a relatively
nonpersistent chlorinated hydrocarbon, is also increasinq in
popularity as a vectoricide. Abate, naled, and carbaryl are
gaininq in importance. Other chemical compounds used
include carbofuran, fenthion and DDT; Maine was the only
state reportinq the use of DDT as a vectoricide in 1970,
None of the New Enqland States permits the use of DDT as a
vectoricide after 1971,
S-3
-------
TABLE 1
QUANTITIES OF PESTICIDES USED FOR INSECT VECTOR CONTROL
IN NEW ENGLAND, 1970
(Ibs. oi active ingredients)
Conn.. Maine Mass.. N-._ik R-._Ia Vt.-
Malathion 550 410 32,000 4,100 X
Methoxychlor 420 10,550 3,804 X
Naled 152 4,430 X
Abate 3,100
Carbaryl 2,626 X
Others 160 42 1,140 X
Total 710 1,024 51,220 10,530 N.A. N.A.
N.A. - Not available
Source: Connecticut State Department of Health
Maine State Board of Pesticides Control
Massachusetts State Reclamation Board
Rhode Island Department ot Natural Resources
New Hampshire Pesticide Control Board
S-4
-------
Vermont: Pesticide Advisory Council and
Division of Plant Pest Control,
Department of Agriculture
Vectoricide use on Cape Cod as reported by the Cape Cod
Mosquito Control Project is shown in Table 2. On Cape Cod,
TABLE 2
MOSQUITO LARV1CIDES USED ON CAPE COD, 1930-1971
Period
Material
Final Formulation
Quantity
(Active
Ingredignts)
1930-1942 Fuel Oil
19 30-19 U2 Pyrethrwns
1945-1956 DDT
1957-1961 Fuel Oil
1957-1961 Dieldrin
1962-1965 Abate
1962-1965 Paris Green
1966-1969 DDT
1966-1969 Malatniori
Various
6.25% in fuel oil
Surfactant 1:400
2$ granular
2-1/2 oz, in 50
gals, water
10* granular
10/i granular
2.4 in fuel oil
1970-1971 Larvicide Oil As received
Not recorded
lest
quantities
only
2500 Ibs/yr
4000 gals/yr
200 Ibs/yr
160 Ibs/yr
800 Ibs/yr
400 Ibs/yr
250 Ibs/yr
3000 gals/yr
S-5
-------
Source: "History of the Cape Cod Mosquito Control
Pro-ject, 1928-1971"
concern about the potential for adverse effects on the
environment w^s instrumental in curtailing the use of
persistent chlorinated hydrocarbon insecticides such as DDT
and dieldrin in favor of more reaaily decomposable phosphate
insecticides. However, even these materials have now been
discontinued, arid the sole vectoricide reportedly used on
Cape Cod in 1971 was mosquito larviciding oil. There are no
reports of mosquito adulticiding work on Cape Cod.
Cape Cod includes 50 square miles of salt marshes and 5
square miles of freshwater swamps in addition to 170 qreat
ponds (above 10 acres). In the past ten years, an average
annual use of 650-950 pounds of pesticides (active
inqredient banis) nas provided acceptable control of
mosquitoes on these 32,500 acres. These low rates of
application were accomplished by making spot treatments by
hand to only those stagnant pools and puddles where large
numbers of mosquito larvae were identified, Thus, with
proper timing and precise placement, the quantities of
vectoricides can be held at low levels.
In the Bass Hole Marsh in Dennis (Chase Garden Creek
section) and the Herring River Marsh in West Harwich, we
carried out intensive studies of the uses, effects, and
residues of vectoricides. The quantities and products
reported in use followed much tiie same pattern as elsewhere
on Cape Cod (Table 3) .
S-6
-------
TABLE 3
MOSQUITO LARVICIDES USED IN TWO CAPE COD MARSHES
(cumulative, active ingredients)
Bass Hole
(Dennis).
Herring River
(w. Harwich)
1961-1965
1966-1970
1966-1970
1970-1971
Fuel Oil
Abate
Malathion
Larvicide Oil
80 gals,
0.2 Ibs,
33.8 Ibs.
30 gals.
53 gals.
0.2 Ibs.
7.6 Ibs,
12 gals.
Source: Data supplied by Cape Cod Mosquito Control Project
During the period 1961-1965, the principal larvicide
was a mixture of common fuel oil plus a surfactant to permit
even spreading and application. Small quantities of Abate
were used in 1966-1970, together with slightly larger
quantities of malathion. The quantities of each material
used in individual years during the period was a function of
the severity of larvae build-up. The work crews of the Cape
Cod Mosquito Control Project were instructed to apply
vectoricide only after the need had been identified and
measured. Furthermore, the practice was to treat only
depressions where water remained at low tide, thus only a
S-7
-------
relatively small portion of the marsh was treated. The
areas studied cover over one square mile each, or more than
1280 acres, but quantities used suggest that much less than
1 percent of the surface was treated.
Beginning in 1970, and continued in 1971, a larviciding
oil was again used in both of these marshes. Unconfirmed
reports indicate that the new larviciding oil is not
completely satisfactory, since it does not always kill
quickly and requires repeated visits to treatment areas in
order to check the completeness of kill.
Need for Acti.on—State agencies should be given the
authority and funds needed to develop records of pesticide
consumption in sufficient detail to permit analysis of data
to identify use patterns, and promote more effective
monitoring and control.
Methods of Application
In New England, mosquito adulticidinq normally is done
by machine, and the ultra low volume (ULV) method has become
the most widely used. Both thermal and cold fogging
machines are used, and offer the advantages of covering
S-8
-------
large areas with well dispersed aerosols in short periods of
time. Indiscriminate use, however, may lead to wind drift
and application of pesticide chemicals directly to live
waterways.
High volume equipment is seldom used for mosquito
control by mosquito abatement organizations but it is
commonly used by cities and towns to spray large trees. In
densely populated urban areas there is little open soil to
absorb run-off and drip, and this method permits entry of
pesticides into the water environment through the storm
drain system. Pollution from this source is often
attributed, wrongly, to mosquito abatement activities.
Larviciding, when done by hand, can be controlled
precisely to treat only those pools that are heavily
infested. Spot coverage averaging less than one percent of
salt marsh areas has proven successful on Cape Cod.
Larviciding by machine, on the other hand, cannot be
controlled as precisely and some non-infested areas are
treated.
Major materials used for larviciding in New England
include a two percent solution of malathion in fuel oil, a
similar solution of methoxychlor, a water solution of Abate
varying from 0.05% to 0.10X, and mineral oils which are
refined especially for use as larvicides. Surfactants may
be used with all of these liquid formulations.
S-9
-------
Granular formulations of the above materials are also
available throughout the area. Formulated on sand and other
carriers at low concentrations, these materials can be
spread mechanically by aerial or ground equipment. Hand
spreading may not be feasible because of the acute toxicity
of the materials.
Route Into Waters
Vectoricides enter the aquatic environment through both
intentional and accidental means, Intentional is more
important in New England, since vectoricides are applied in
and around swamps and marshes; subsequent rains or flooding
may move the materials directly into the water environment.
Wave and tidal action in salt marshes may also move
vectoricides from the point of application into the liquid
phase and distribute them to other areas. Nonresidual
materials {such as organophosphates, carbamates, mineral
oils, etc.) do not move far from where applied since
decomposition to harmless forms occurs rapidly.
The practice of applying vectoricides to storm drains
in urban areas may lead to direct contamination of the
aquatic environment. Even light showers may generate
S-10
-------
sufficient run-off to rapidly transport minerals from the
individual drains to outflows. Highly toxic materials thus
transported can have significant acute toxicity effects on
nontarget organisms, particularly if showers occur soon
after the pesticide is applied.
Substantial quantities of pesticides are used for
agricultural purposes in New England, but are normally
adsorbed by soil particles and held in place until degraded.
Pesticides applied to cranberry bogs, however, may be
released into the aquatic environment when bogs are
improperly drained.
Accidental means of pesticides entering the aquatic
environment include spills during handling, transportation
and storage. Trucks which transport pesticides to
1
distribution points in New England have been involved in
accidents which resulted in broken containers and loss of
material. Prompt handling {detoxification and clean up) by
specially trained crews of experts (under the direction of
the National Agricultural Chemicals Association's Pesticides
Safety Team Network) has averted disaster to nunnans and
large animals, but the traces which remain have the
potential for water contamination. Improved and more
durable packaging, economically possible with the more
expensive vectoricides currently used, should re.luce
accidental release.
S-ll
-------
The disposal of empty containers is a serious problem
in New Enqland. Some states have issued clearly defined
regulations identifying both the prescribed methods and
correct disposal sites, but have experienced significant
difficulties in getting municipalities to implement them,
Most local health officials appear to place low priority on
the problem, and as a result there are few disposal systems
that have set aside land fill areas specifically for this
purpose. Also, many localities do not have proper land fill
areas and containers cannot be buried. During our study we
noted considerable reluctance among commercial pesticide
users to discuss this problem, since many are not able to
comply with the regulations.
Once released into the environment, pesticides move by
several means. Principal mechanisms for vectoricides in New
England appear to be: (1) sediment transport, where
compounds are adsorbed to finely divided particles of soil
(clays) or organic matter, and (2) atmospheric transport of
their volatile fractions. Since most soils on Cape Cod are
sandy and with low clay contents, pesticides more commonly
adsorb to organic matter such as mulch, bark, straw, leaves,
etc, Heavy showers, tidal action, and flooding move these
easily, but the rate and direction of transport can be
predicted. Less is known about atmospheric means of
transport.
S-12
-------
Nj~<=3 J^or Action — Regulations regarding the disposal of
empty pesticide containers should be improved and
standardized throughout the New England states. Provisions
should he made to check the adequacy of local disposal
areas.
Impact on the Environment
There is a limited diversity to the flora and
macrofauna (fish, birds, mammals) in the two salt marshes we
studied; however, there is a great diversity ot microfauna.
In addition to the mosquitoes and other insects that inhabit
these areas, there are innumerable invertebrate larvae,
worms and shellfish. The marshes act as efficient energy
nutrient traps and supply a major portion of the food for
commercially important fishes which pass Cape Cod in
seasonal migrations. Tidal action distributes the food to
eacn life form both within and at the mouth of the marsh,
and this periodic flushing by the tide results in a rapid
turnover of materials.
Simply put, the food chain in these salt marshes begins
with salt grasses which decompose via machine action to
-------
detritus. The detritus, algae and diatoms, are consumed by
small fish, shellfish and other filter feeders. Larger
predator fish, eels, and lobsters, are at the top of the
food chain. Tne effect ot birds is minimal when compared to
the total system. The interrelationships between prey and'
predator provide for a complex web. These organisms carry
out their life cycle in the water, or land periodically
covered by it, in close association with each other. One
species may serve as prey lor another species during early
stages of development, but the roles are reversed later.
We surveyed the literature for both the acute and
chronic effects of Abate, DDT, malathion, and mineral oils
on typical salt marsh organisms. Abate, which kills
mosquito larvae at a concentration of 11 parts per billion
(ppb) or less, must be present at a concentration of greattir
than 1 part per million (ppm) to affect -juvenile killifish.
DDT, which is not now usad for mosquito control in New
England, kills juvenile killifisn at only one-fourth the
concentration needed for mosquitoes and also may concentrate
to toxic levels in animals high up in the food chain.
Malathion is not toxic to minnows at the concentration used
for larvicide work. Mineral oil (Flit MLO) has no effect on
mummichogs at application rates greater than ten times that
reguired for mosquitoes.
S-14
-------
Our observations indicate that there is no measurable
long-term effect on the typical biota found in these marshes
which can be attributed to the materials and treatment
techniques used by the cape Cod Mosquito Control Project.
Maximum vectoricide treatment levels have been consistently
below the levels necessary to affect more organisms.
According to their data, the Project's highest application
rate was 0,02 Ib. malathion per acre to a limited area of
the marshes; even if localized mortality occurred, the
effects would be quickly neutralized by repopulation from
adjacent areas,
It is our general conclusion that the local, spot
application of vectoricides as practiced during the past ten
years by t'he Cape Cod Mosquito" Control Project to the
stagnant waters at the fringes of the marshes does not
produce a risk of significant toxic effects to important
species, Our analysis has included species of interest for
commercial and aesthetic considerations. No human health
problem has been predicted.
Deqradation_andMetabolism
Studies of pesticide metabolism are helpful in reaching
rational assessments of hazards arising from their use.
S-15
-------
Most compounds used tor mosquito control are complex,
synthetic organic chemicals, and the action of natural
processes (chemical or microbial) produce degradation
products which have ditterent properties and effects on the
environment. In order to understand the potential effects
on nontarqet organisms from the treatments used in the two
marshes, the literature was surveyed tor studies dealing
with those chemicals. In the light of these findings, soil
and water samples from these marshes were analyzed to
determine how much of the chemicals used (or their
degradation products) were present. Although the scope of
the program was limited, and the results from our testing
program are not statistically valid, we believe that the
results are indicative of the general levels of pesticides
that are residual in those two salt marshes.
The major breakdown products of DDT is DDD and DDE, and
these, together with DDT, have been found up to ten years
after its application. The quantities found, however, are a
function of the particular environment; in moist, fertile
soils, DDT may disappear in a few months, but up to 30
percent may be retained after ten years in the upper,
organic layers of forest podosols. in general, it appears
that DDT tends to degrade more rapidly where a large and
varied soil microbe population is present, and persist for
the longest periods of time in environments such as aquatic
S-16
-------
and other areas where microorganisms are more limited in
number and kind. The amount of nutrients available for
growth of microorganisms also is of importance.
Dieldrin is more resistant to breakdown than DDT but on
exposure to sunlight is likely to form photodieldrin, which
is more toxic to rats and pigeons than dieldrin and less
toxic to certain fish. Aldrin and several unnamed
metabolites are formed by tne actions of a number of
microorganisms, but most species of soil microbes are
incapable of degrading dieldrin. Most studies classify it
as a highly resistant compound, with major losses from soil
by means ot volatilization and sediment transport.
Malathion is less stable than most other insecticides,
and may be degraded within 24 hours of its application to
some soils. Biodegradation appears to be the major means of
decomposition in aquatic environments, although aeration
alone has some effect. Biological oxidation of malathion
produces malaoxon, the active insecticidal compound, which
undergoes a parallel degradation route. Other malathion
degradation products are relatively harmless, particularly
in the small quantities which can be found at any one time
in the environment.
Abate is a newer material, and fewer studies have been
conducted with it. The major degradation products seem to
S-17
-------
be its sulfoxide and sultone derivatives, neither of which
have been extensively tested for their effects on typical
aquatic biota. Abate is somewhat more resistant to
degradation than malathion, but the limited studies that
have been conducted seem to indicate that Abate is not
deleterious to nontarget organisms. We suggest further
research on its degradation and metabolism should be
undertaken.
Historical vectoricide treatments in the two salt
marshes on Cape Cod included the four chemicals discussed
above {DDT and dieldrin were used prior to 1961, and
dieldrin is currently recommended for insect control in
cranberry boqs in the area) . Samples of soil and water were
taken from the general areas where these vectoricides had
been applied and where observations of effects on typical
biota were made. In consultation with our analytical
chemists, analyses were carried out by Dr. Karl Deubert of
the University of Massachusetts Agricultural Experiment
Station at Waroham. Dr. Deubert has been active in
determining soil pesticide levels on Cape Cod, and was able
to correlate these results with those done earlier.
The general findings were as follows:
- Residue levels are low, averaging 0.026 ppm DDT,
0.007 ppm DDE, and 0.021 ppm dieldrin.
S-18
-------
- No evidence of malathion or Abate was found.
Although the number of samples does not provide a
firm statistical base, there is some evidence that
DDT levels have decreased by a factor ot 10 (from
0,2 to 0.026 ppm) in two years, Dieldrin levels
showed little or no change compared to those found
two years ago. However, we must emphasize tnat
further testing of a larger number of samples would
be necessary in order to confirm these results.
The low levels of DDT, DDE, and dieldrin found
suggest that these residues may be due to "steady
state" pollution from atmospheric and ocean
transport sources rather than residual front previous
treatments for vector control.
Need for ActjLon—Research programs on the degradation
and metabolism of newer compounds, such as Abate and mineral
oils, are needed. Monitoring programs to measure the level
of persistent compounds should be expanded and a data bank
on the distribution of pesticide residues in the biota of
salt water marshes should be developed.
S-19
-------
and Regulations
The existing laws and regulations in Massachusetts and
some other New England states generally provide a broad and
flexible means tor controlling pesticides. However, they do
not provide adequate environmental protection because little
effort is made to assure that actual practices and
procedures in the sale, transportation, storage, use and
application of pesticides conform to existing laws and
regulations. Information distribution, monitoring,
investigation, and enforcement are lacking, largely because
of insufficient funds, personnel, and facilities.
Registration, labeling, and licensing mechanisms are used
perfunctorily. They have some informational value, but
little control value other than creating a framework inside
which incidents and problems can be worked out.
The major reason for this state of affairs is lack of
funds for personnel (administrative, legal, technical) and
facilities (laboratory, etc.) to control pesticides.
Another reason is the lack of coordination between
individual state agencies and between state and local
agencies concerning their roles in pesticide control
activities,
Today, if the public took a close look at the
regulation of pesticides in New England, it would find that
S-20
-------
very little of the authorized regulation is being
effectively exercised. As a result, the general public and
the environment is mostly at the mercy of the common sense
and degree of public interest that persons who use or deal
with pesticides voluntarily bring to their work.
This lack of effective control under existing laws and
regulations has not escaped notice. There are citizens and
groups who have expanded their use of lawsuits,
investigations, public accusations, written articles, and
political activities to assure that pesticides are more
adequately regulated. For example, in Massachusetts, any
ten citizens, because of a new law passed in 1971, can bring
action in the courts, whether or not they are directly
affected by damage or potential damage to the environment,
This, and similar actions will likely become more important
because citizens have not obtained a prompt, adeguate
response when they have gone to the existing regulatory
agencies in the various states.
If state and local governments do not begin to
effectively regulate pesticides soon, these citizen-
sponsored lawsuits and other public actions are likely to
produce unbalanced solutions for pesticide control issues,
There are many legitimate uses of pesticides, including
those necessary to provide acceptable control of insect
vectors, Some of these uses could be in danger of
S-21
-------
elimination by aide-door solutions based heavily on leqal
and political criteria. Most pesticide control issues
require a great deal ot flexibility, accuracy, and delicacy
in irri.vi.nq at balanced decisions. Regulatory agencies,
operatinq properly, can more effectively leal with this
broad range of issues in a proper mariner.
Alternatiye Methods_of_Control
A study of the life cycle of the mosquito indicates
tnat it spends a great deal of time in the aquatic
environment, passing through all three juvenile stages (ova,
larva, and pupa) in this medium. Most species select small,
stagnant pools or puddles of water, wnich often are
contaminated with a great variety of impurities which have
run off trom surrounding lanu areas. These impurities
present some practical difficulties in developing biological
methods of control.
At the present time, the use of mosquito-eating
predator fish appears to offer the best overall method of
natural control, both in fresh and salt water. In the
Southern United States, Gambusia sp. thrive and may live
almost exclusively on mosquito larvae. Transplants of these
fish have been successful as far north as Ohio, but most
S-22
-------
efforts to establish them in new England have failed. In
the Cape Cod salt marshes there are small salt water fish,
such as mummichoqs and striped killifish, in small streams
and drainage channels. Where these fish are present in
larqe numbers, the population of mosquito larvae in
surrounding pools is very low. The problem is to keep these
fish in intertidal areas during low tide; as the water
retreats, the fish tend to go with it. In certain areas,
shallow holes can be dug in tne marshes which will retain
water even at low tide and provides a sanctuary for the
fish. Then, at high tide, the fish are present in large
numbers, move out of the holes, and prey on mosquito larvae.
A number of other biological means of control have been
described, and some have been proposed for use. The use of
disease pathogens has riot yet been successful because of the
genetic resistance to diseases that mosquitoes have
developed while living in contaminated environments. The
sterile male technique, whereby artificially sterilized
males are released in large numbers to mate with natural
females, potentially can be useful in areas where only one
or two species of mosquitoes need to be controlled.
Synthetic materials wnich mimic the action of juvenile
hormones have been shown to inhibit pupal development, in
laboratory tests and limited field trials. One serious
problem to be overcome, however, is the destruction of these
S-23
-------
compounds by only a few hours of exposure to sunlight.
The most important nonchemical method of controlling
salt marsh mosquitoes in New England today is water
management by the use of adequately planned and maintained
drainage ditches. When coupled with the leveling of small
depressions, drainage ditches provide channels for the water
to move completely out of the intertidal areas, small pools
and puddles are eliminated, and mosquitoes are deprived of
preferred places to lay eggs. The ditches must be regularly
maintained to avoid silting and debris accumulation which
can interfere with the flow of water. In the two salt
marshes that we studied on Cape Cod, it is believed that the
low use of vectorocides has been made possible by the
properly designed and maintained drainage ditches.
While natural controls such as drainage ditches and
predaceous fish offer important means of keeping mosquito
populations down to acceptable levels, pesticides are
required from time to time. The history of vectoricide
application to salt marshes in the Cape Cod area indicate
that applications may be necessary every year, or riot more
than once in five years, depending mainly on weather
patterns. When mosquito build-ups appear imminent,
treatment with a larviciding agent is necessary. When
conditions are exceptionally favorable for mosquito growth
and reproduction, several applications to the same area may
S-24
-------
be necessary. For practical purposes, we believe that
mosquito populations can be controlled at acceptable levels
through the proper and timely use of small quantities of
hand-applied larviciding agents.
S-25
-------
PART TWO — REPORT AND APPENDIX
I. STATEMENT OF WORK
The objective of this work was to carry out a case study of
the pesticides used for insect vector control on Cape Cod in New England,
and their effects on the natural environment. An investigation was con-
ducted to provide quantitative documentation of the kinds and quantities
of pesticides used, their route from the point of initial application into
the water environment, and their ultimate effect on the ecosystems of the
Chase Garden Creek section of the Bass Hole Marsh in Dennis, and the
Herring River Marsh in Harwich. Further objectives were to analyze the
laws and regulations concerning the use of pesticides in New England
generally, and for mosquito abatement in Massachusetts particularly, and
determine the protection to the natural environment which they provide.
Additionally, the importance of non-chemical methods of controlling
mosquitoes was investigated.
The major findings of this work, including the needs for action,
were summarized in Part One of this report.
-------
II. NATURE AND EXTENT OF VECTOR PROBLEMS
A. DISEASE VECTORS
Two disease problems caused by insect vectors are known in
New England, Eastern equine encephalitis (EEE) transmitted by mosquito
and Rocky Mountain spotted fever (RMSF) transmitted by the American dog
tick. Massachusetts is the only Northeastern state reporting problem
areas on both disease vectors.
Approximately 50 human cases of EEE have occurred in the south-
eastern part of the state in the last 35 years,' with a recurrence taking
place every ten years. The largest number of human cases—32—were
reported in 1936. The disease appeared again in 1946 causing 12 cases,
then in 1956 causing six cases, and the last human case was reported in
1970. Before human cases are reported, EEE becomes a serious problem in
the equine population. In 1970, although there was only one human case,
54 confirmed equine cases were reported in southeastern Massachusetts. A
recurrence of EEE was noted in 1971 with ten confirmed cases of horses
reported dead but no incidents reported on humans.
The second disease problem, Rocky Mountain spotted fever spread
by the American dog tick, also is known only in the southeastern part of
Massachusetts. Nearly all cases—which have been reported at an average
rate of one a year for the last 30 years—occurred in the Cape Cod area.
Scattered cases of EEE and RMSF are reported from time to time
in the Boston area or inland, but their origins have all been traced back
to the southeastern part of the state.
Private communication with Dr. Waterman, Department of Public Health
Commonwealth of Massachusetts, Boston, Massachusetts. '
-------
Neither Rhode Island, New Hampshire nor Maine have reported any
major problem area of disease vectors. New Hampshire and Maine consider
that the southeastern parts of their states have a potential for disease
vector problems because of the proximity to Massachusetts, but cases have
not been reported.
Vermont has had cases of tularemia transmitted by deer flies,
and a total of 30 human cases have been reported over the years to the
Vermont Pesticide Advisory Council with a 10% mortality incidence. Out-
breaks of other diseases caused by vectors have not been reported.
B. NUISANCE VECTORS
Vectors are considered a nuisance problem throughout New England.
The mosquito population, although spread throughout the area, causes
greater problems in the coastal areas due to salt marshes and a large num-
ber of ponds. The nuisance is also more severe along the coast because
population and summer resorts are concentrated more heavily in that area.
Like mosquitoes, black flies are a nuisance problem throughout the region,
but only a few control programs have been established.
In addition to mosquitoes and black flies, green flies are
reportedly a nuisance in the state of New Hampshire, especially in the
mountain area. Green head flies and culicoids are reportedly a nuisance
problem along the coastal areas of Massachusetts.
Maine reports nuisance mosquito, black fly, and deer fly
problems, but only mosquitoes and black flies receive treatment. There
are no organized treatment areas, and most work is done privately around
lakes and ponds, drive-in theaters in low-lying areas, and homeowner
fogging.
-------
III. PESTICIDES USED FOR VECTOR CONTROL
A. KINDS OF MATERIALS USED
Probably the first method of chemical control of mosquitoes
consisted of the spreading of petroleum oil over standing water on the
marsh lands. The oil killed the larvae by eliminating oxygen at the
water surface. Chemical products can be used either to eliminate the
insect at a larval stage (larviciding) or to eliminate it in the adult
stage (adulticiding). Under most conditions, control procedures against
mosquitoes are most effective and most economical when designed to
eliminate larvae. Mosquito larvae live only in water, and the manage-
ment of water is the basic means of control, but often it must be
complemented by pesticides, chemicals, or oils, known as larvicides. In
areas where stagnant water contains only one brood of mosquito larvae,
one well-timed application of a suitable pesticide in the spring may be
all that is necessary. Where several broods are present, a pesticide
application for each brood may be required.
Today, many different materials are used as larvicides, includ-
ing mineral oils (such as Flit MLO), Abate, malathion in oil, and others.
The oils provide effective control by killing mosquitoes in all their
aquatic stages—ova, larva, and pupa. The oil on the water surface has
a lasting time of 48 to 72 hours. Kill may be rapid when water is calm,
but slower and less positive with wave action and wind. In some cases,
the larvae may live but appear to be in suspended animation, and control
crews have elected to re-treat with chemical pesticides. Control of
-------
adult mosquito populations is done primarily by chemical methods. The
control is mostly temporary and the effectiveness depends not only on the
thoroughness of the control methods, but also on the size of the area
treated, the species, and the life stages. Since some adult mosquitoes
may fly several miles, adulticiding programs must cover a large area.
These insects migrate so far and so quickly that an individual cannot ob-
tain any measurable relief by his own efforts, and entire areas must be
treated.
In chemical control there are at least two types of treatments:
in one, the insects are killed almost instantly after application, by
contact with the insecticide which has a high acute toxicity; in the other,
long-lasting components have a residual effect. With proper timing and
thorough, coverage, an adult mosquito population can be reduced to acceptable
levels quickly with materials such as malathion and naled. On the other
hand, treatment with methoxychlor may result in less rapid but longer last-
ing control since it does not degrade as quickly as the phosphates.
In the case of other nuisance insects in New England, such as
the green head fly, chemical control (when used) is applied mostly to the
adult population. Larval control is difficult because the breeding cycles
are not well known and breeding sites have not been adequately described.
When chemicals are used for green head fly control, malathion is popular.
On Cape Cod, nonchemical methods such as the Manitoba boxes (cages) appear
to provide some relief by trapping females.
B. SPECIFIC MATERIALS USED
Until its application was banned, DDT was the most popular pesti-
cide used for vector control in New England, but in 1970 only the states
-------
of Maine and Vermont reported its use. Malathion, naled and methoxychlor
are currently the most popular pesticides used to control the adult
mosquito population. Mineral oils, Abate, methoxychlor and malathion in
oil are the most popular larvicides.
C. QUANTITIES USED
Shown in Table III-l is the estimated total pesticide consump-
tion within each state in New England. These estimates, from the New
England Governor's Conference, are not based on exhaustive surveys, but
rather on the records kept in recent years by agencies in some states and
personal knowledge and experience of officials in other states. Available
data on the types and quantities of pesticides used in New England for
mosquito control is largely incomplete. For the most part it represents
only that portion of the control program that falls within the juris-
diction of a local or state agency. Some states can estimate the
quantities from reports required of custom applicators, but others have
not yet established sufficiently good record-keeping systems.
The state of New Hampshire requires that all pesticide appli-
cators be registered with the Pesticide Board, including government
agencies, and make an annual report of the types and amount of pesticide
used annually. It is the only one in the New England region that can
provide state-wide information on the materials used for vector control.
In the other states where individual or community efforts are not
required to report to the state's pesticide office, no records are kept
that will permit extracting comprehensive data as to the types and amounts
of pesticides used.
-------
TABLE III-l
ESTIMATED CONSUMPTION
OF PESTICIDES IN
NEW ENGLAND, 1969
(thousands of pounds active ingredient)
Kind
Farm & Commercial
Insecticides
Malathion
Methoxychlor
Carbaryl
DDT
Chlordane
Others
Sub-Total
Herbicides
Fungicides
Total
Household
Grand Total
Connecticut
20.5
N.A.
39.7
9.2
26.5
68.3
164.2
51.2
7.9
546.7
1243.0
1789.7
Maine
102.0
22.0
83.0
1.0
N.A.
1636.0
1844.0
267.0
2610.0
4721.0
543.0
5264.0
Massachusetts
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
1206.4
523.7
963.8
2693.8
1554.0
4247.8
New Hampshire
5.7
N.A.
10.3
12.6
4.5
48.9
82.0
38.4
74.5
194.9
202.0
396.9
Rhode Island
4.2
N.A.
12.1
11.8
2.1
N.A.
N.A.
N.A.
37.5
259.0
296.5
Vermont
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N,A.
160.0
121.0
281.0
N.A. = Not available
Source: "Report on Use and Control of Pesticides in New England," The New England Governor's Conference
Committee on Environment, July 7, 1971.
-------
Table III-2 presents partial information on the products used
by the individual states. This data is subject to the following comments:
• New Hampshire has records of most of the pesticides
used in the state for vector control because the state
requires that all applications of pesticide made by
licensed persons to the land of another be recorded
and records made available. The Board of Pesticides
keeps yearly records (since the time of its formation)
of the types and quantities of pesticides used in the
state. Data prepared by the Board for this study ex-
cludes applications made to private lands by owners.
• Massachusetts statistics represent the estimated pesti-
cide requirements for vector control as submitted by
the eight individual Mosquito Abatement Districts to
the State Reclamation Board. Since these requirements
are estimated substantially in advance of use, there may
be differences in the final use pattern. Data does not
include products used by municipalities, communities
and individual applicators, and no record in this respect
is maintained at the state level.
• Maine data reported by the State Board of Pesticide Control
represents only partial information since the regulation
establishing required reporting of pesticide usage by
custom applicators was enforced only during 1970.
8
-------
TABLE III-2
ESTIMATED CONSUMPTION OF PESTICIDES FOR MOSQUITO CONTROL
;
IN NEW ENGLAND
New Hampshire
Massachusetts
Maine
Connecticut
VO
v>aeiiu_cais
:tive Ingredients)
Malathion
Methoxychlor
Carbaryl
Abate
Carbofuran
Naled
Fenthion
DDT
Total
Mineral Oil (gal.)
1970 1969
4,100 4,100
3,804 3,800
2,626 2,600
1,000
10,530 11,500
1968
4,100
3,800
2,600
1,000
11,500
1970
32,000
10,550 -
3,100
140
4,430
1,000
51,220
7,000
1969 1968
26,315
19,236
11,215
42
2,180
1,624
60,612
1970 1969 1968 1970 1969 1968
410 550 550
420
152
5 160 160
37
1,074 710 710
600
Sources: Connecticut State Department of Health
Maine State Board of Pesticide Control
Massachusetts State Reclamation Board
New Hampshire Pesticide Control Board
Rhode Island Department of Natural Resources—no data available
Vermont Pesticide Advisory Council—no data available
-------
• Connecticut data refers to pesticides used by the
state to control salt marsh mosquito species along
the shore, and does not include pesticides used for
freshwater mosquito control. Inland control is left
to the individual cities and towns for solution and
records are not available at the state level. To
obtain accurate and complete information would require
contacting 169 towns in the state, first by letter and
then by follow-up visit.
• Vermont: No figures exist on the actual use of
pesticides in Vermont, although estimates have been
made by state officials. In a report to the Governor,
the Vermont Pesticide Advisory Council stated that
there are no state laws governing the use of pesticides
by public and private agencies or individuals and
records of pesticide use in Vermont are incomplete and
preclude meaningful assessment.
• It is believed that relatively little amount of chemical
pesticides have been used in Vermont, cotapared with the
previous decade. The only known record of pesticide use
for vector control is for DDT in 1967, when 600 pounds
was delivered to local associations and custom applicators
(ground equipment) for use in mosquito and shade tree
spraying in the Burlington, St. Albans, and Grand Island
areas. As of December 1971, however, usage of DDT will
be banned in the state. New measures concerning
10
-------
licensing of custom applicators by the Pesticide Advisory
Council will improve procedures for record-keeping of
pesticide application throughout the state of Vermont.
D. PESTICIDES USED ON CAPE COD
Kinds and quantities of pesticides used for vector control on
Cape Cod by the Cape Cod Mosquito Control Project are shown in Table III-3.
As reported by the Cape Cod Mosquito Control Project, the official abate-
ment district for Barnstable County, fuel oil has been the principal
material used over the years. Chemical pesticides were used after World
War II, when the effectiveness of DDT was shown. However, concern over
possible residue build-up, together with signs of insect resistance to DDT,
resulted in a shift to other materials.
Dieldrin was used for about five years but was replaced with
Abate (an organophosphate) and-Paris Green (copper acetoarsenite). These
materials were in turn followed by malathion for the salt marshes, and DDT
for the freshwater swamps which offered no outlet to salt water and no
route to estuaries. In 1969 and 1970, these materials were given up in
favor of a new mineral larvicide oil formulated especially for mosquito
larva control,
E. PESTICIDES USED IN TWO SALT MARSHES
Shown in Table III-4 are the kinds and quantities of pesticides
used in the Bass Hole Marsh in Dennis and the Herring River Marsh in
Harwich for the years 1961-1971. The data, as supplied by the Cape Cod
11
-------
TABLE III-3
MOSQUITO LARVICIDES USED ON CAPE COD, 1930-1971
Period
1930-1942
1930-1942
1945-1956
1957-1961
1957-1961
1962-1965
1962-1965
1966-1969
1966-1969
1970-1971
Material
Fuel Oil
Pyrethrums
DDT
Fuel Oil
Dieldrin
Abate
Paris Green
DDT
Malathion
Larvicide Oil
Final Formulation
Various
6.25% in fuel oil
Surfactant 1:400
2% granular
2-1/2 oz. in 50 gal. water
10% granular
10% granular
2% in fuel oil
As received
Quantity
(Active Ingredients)
Not recorded
Test quantities only
2500 Ibs. per year
4000 gals, per year
200 Ibs. per year
160 Ibs. per year
800 Ibs. per year
400 Ibs. per year
250 Ibs. per year
3000 gals, per year
Source: "History of the Cape Cod Mosquito Control Project, 1928 to 1971"
-------
TABLE III-4
Year
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
Fuel Oil Plus
Surfactant (gal.)
Bass
Hole
36.0
44.5
3.0
Herring
River
6.0
21.0
9.5
10.5
6.0
PESTICIDES USED FOR MOSQUITO CONTROL IN
TWO CAPE COD MARSHES, 1961-1971
(Active Ingredient Basis)
Abate (Ibs.) Malathion
Bass Herring Bass
Hole River Hole
0.03 0.01 2.76
15.52
13.45
(Ibs.)
Herring
River
0.17
1.21
3.28
1.38
0.19
0.15
0.01
2.03
1.55
Larviciding
Oil (gal.)
Bass
Hole
Herring
River
18.0
11.5
8.0
4.0
Note: Bass Hole Marsh includes Chase Garden Creek and tributaries.
Herring River Marsh (West Harwich) between Bells Neck and Lothrop Roads.
Source: From data supplied by the Cape Cod Mosquito Control Project.
-------
Mosquito Control Project, shows malathion to be the most important chemical
used during this period, but oils made up the largest total quantity. A
shift from oil to chemical back to oil is noted, reflecting dissatisfaction
with the chemicals.
14
-------
IV. METHODS OF APPLICATION AND TYPES OF MATERIALS USED
There are two general types of pesticide applications used for
mosquito control in New England: larviciding and adulticiding. Each
can be done mechanically or by hand, but in general, adulticiding is done
both by machine and by hand.
A. ADULTICIDING
The modern control of adult mosquitoes is most successfully
carried out by aerosols, using ultra-low volume, thermal and non-thermal
equipment. Both ground and aerial equipment are used in New England.
The popularity of this type of application focuses around:
• The speed with which large areas can be covered with
well-dispersed aerosols.
• The small quantities of material and diluent needed
reduces the number of refills and speeds up the
operation.
• The control of droplet sizes provides flexibility in
confining applications to the target areas.
Indiscriminate use of aerosol equipment could provide a route
of pesticides into the water environment. There is a danger of intro-
ducing chemicals accidentally into live streams when large areas are
covered. Variations in wind speed or direction, and variable temperature
gradients between different elevations can mean trouble for careless
operators who do not adjust their machines accordingly. Aerosols which
15
-------
are allowed to drift out of the target areas are a major source of concern
to regulatory agencies, and account for a sizable number of complaints
from property owners and inhabitants.
The use of high-volume equipment has been reduced in New
England, and most mosquito control programs use other means. There are,
however, several cities and towns that still use hydraulic machines to
cover large trees with ground equipment. The large volumes used (up to
100 gallons or more per acre) may cause drip and runoff problems, partic-
ularly in urban areas where paved streets, sidewalks, parking lots, etc.,
cut down on the area of soil available to absorb and degrade these materials.
B. LARVICIDING
In our study area all larviciding has been done by hand using
back-pack sprayers. With this equipment, precise applications of larvi-
cides can be made that will reduce or eliminate the entry of materials
into the water environment. Spot treatments of stagnant pools and puddles
can be made, and wasting chemicals on other areas is avoided. There are
obvious savings in materials, although there are also high labor costs.
Mechanical larviciding is done with low-volume, liquid aerial
or ground equipment, and with broadcast spreaders of granular materials.
Indiscriminate use of mechanical larviciding, like adulticiding, can place
pesticides where they can be transported into water. Equipment used to
spread liquid larvicides include standard low-volume machines which can
apply in the range of 5-10 gallons per acre. Helicopter-mounted booms and
nozzles can be calibrated at these rates. Ground equipment may be the
same as used for aerosols, but adjusted to provide larger quantities of
larger droplets.
16
-------
Granular broadcasters, aerial or ground, consist normally of a
spinning disk which imparts centrifugal force to each granule and moves it
a measured distance from the machine. Particle size, disk speed, and
forward speed of the carrying vehicle all can be varied to change the rate
of application. Normal rates are in the range of 10-20 pounds per acre of
formulated materials.
C. FORMULATIONS OF MATERIALS USED
1. Larvicides
In New England, the major material used in 1970 for larvae
control was malathion, and the major formulation was 2% active ingredient
dissolved in fuel oil. Starting material is usually 55-57% emulsifiable
concentrate containing about 5 pounds malathion per gallon. Standard No. 2
fuel oil is the major diluent, and surfactants (spreader-stickers) may or
may not be necessary depending on the concentrate used.
Abate, an organophosphate compound produced specifically for
larviciding, is normally used in a water solution at the rate of 5-10
gallons per acre. The emulsifiable concentrate tests about 49% and con-
tains 4 pounds Abate per gallon. Working solution is made by dissolving
5 fluid ounces of the concentrate in 50 gallons of water.
Mineral oils especially refined for mosquito larviciding (such
as Flit MLO) are normally applied in the same form as received, and not
diluted. Analyses indicate contents of 99% petroleum fractions and 1%
inert ingredients. It is widely believed that the inert fraction may
consist of surfactants.
17
-------
2. Adulticides
The use of ultra-low volume applicators has brought about a
change in materials used to kill flying, adult mosquitoes. Special
formulations of concentrated products are now used widely throughout New
England, the most popular being malathion (95%, 9.7 Ibs. active per
gallon) and naled (85%, 14 Ibs. active per gallon).
When applied in accordance with label instructions, ULV
concentrates differ very little from normal emulsifiable concentrates of
lower dilutions. In these highly concentrated forms, however, they are
more dangerous to handle during transportation and applicator loading.
Accidental spills can release them into the environment where they would
pose a threat to nontarget organisms. Accordingly, a greater burden is
placed on the application supervisor, who must ensure that his operators
have received proper timing and have proper respect for the material.
D. FORMULATIONS OF PESTICIDES USED ON CAPE COD
Early pesticides used on Cape Cod to control mosquito larvae
consisted of fuel oil only. Various formulations of pyrethrums were used
in early years, but sufficient records are not available to define exact
formulations. From 1945 to 1956, the Cape Cod Mosquito Control Project
r-sports that the DDT it used was formulated with 75 pounds technical DDT
(about 99% pure), 10 gallons of Xylene, and 140 gallons of fuel oil.
Application was at the rate of 5-10 gallons per acre. Dieldrin as 2%
granular served as the pre-season larvicide from 1957 to 1961, at the rate
of 10-12 pounds per acre in freshwater swamps, with about one-fourth of
the total area covered. Fuel oil fortified with one pint surfactant to
18
-------
50 gallons was used during the season. Paris Green granules, 10% active,
were used in 1961-1965, together with a solution of Abate consisting of
5 fluid ounces of 49.2% Abate 4E (contains 4 Ibs. active per gallon) in
50 gallons of water. The low quantities applied shown earlier in
Table 1II-4 are based on a general application rate of 10 gallons per acre
of this dilute solution.
When the use of DDT was restarted in 1966, the 10% granular
form was applied to freshwater mosquito breeding areas. On the average,
about 0.1 Ib. active DDT was applied to each acre. Malathion was used
from 1966 to 1970, in an oil solution formulated with 3-1/2 gallons of
57% emulsifiable concentrate (5 pounds active per gallon) in 100 gallons
of fuel oil.
The pesticides used in Bass Hole and Herring River Marshes were
based on the above formulations.
19
-------
V. ROUTE OF PESTICIDES INTO THE WATER ENVIRONMENT
A. INTRODUCTION
The route of pesticides into the water environment has been
categorized broadly as either (1) intentional or (2) accidental. These
routes have been further subcategorized as follows:
(1) Intentional
(a) Agricultural and forestry uses;
(b) Aquatic uses for controlling insects, weeds,
trash, fish, etc.;
(c) Household and garden use;
(d) Municipal and industrial use;
(e) Public health use;
(f) Manufacturing.
(2) Accidental
(a) Accidents in manufacture, handling, trans-
portation, storage and use;
(b) Industrial and municipal wastes;
(c) Agricultural wastes such as crop residues,
food, industrial wastes;
(d) Drift from application or movement by
attachment to soil particles, etc.;
(e) Fires, floods.
20
-------
To varying degrees, all of these represent potential routes of pesticides
used for vector control into the environment of the New England States.
Because of the objectives of vector control some paths of pesticides into
the water environment are, obviously, of much less importance than others;
for example, accidental releases during manufacturing, handling, trans-
portation, storage and use could be expected to be less contributory than
would intentional application near aquatic areas for public health use.
Nevertheless, accidental releases would be expected to have a greater
immediate impact on a localized environment due solely to concentration
effects than the intentional releases which would be contributory to chronic
background levels over long terms. Because pesticides for vector control
may require several handling and transfer operations before their final,
intentional application, our examination of their routes into the water
environment began with tracing their paths from the manufacturing plant
through the distribution channels to the final application points in order
to assess all potential routes for entry into the water environment.
B. HANDLING AND TRANSFER METHODS
The products used in vector control in New England, especially
in the Cape Cod area which is of particular concern to us, basically are
not manufactured in the region, although some formulation may take place.
Consequently, the potential entry into the water environment at manufac-
turing sites is of limited concern in this region. Nevertheless, the
[2 3]
prevention and control of spills of hazardous polluting substances '
demands increasing attention at all stages of formulation, storage, transfer,
[3 41
transportation and distribution. A number of surveys ' have indicated
21
-------
that the loading, transportation and unloading operations are areas of
high potential for spills; furthermore, there are areas where inadequate
provisions often exist for preventing or controlling the spread of spilled
substances.
In New England the pesticides products used in vector control
are shipped into the region by trucks and rail transport. Tank cars and
tank trucks are used when large volume usages justify the economics of such
transportation. The most frequent methods of shipment are in five-gallon
cans or fifty-five-gallon drums for liquid products and plastic-coated
paper bags for solid products. Truck transport can be either in company
or hired carriers. In the case of less than truckload shipments, company
trucks most commonly ship pesticides with other hazardous polluting sub-
stances, e.g., oils. In the case of hired carriers' transporting mixed
cargoes, there is no direct control over the product mix being shipped.
Accidental spillage or leakage of pesticides during shipment
such as might occur in truck or rail accidents, can be reported by the
operators to the Pesticides Safety Team Network in order to obtain advice
and assistance in prompt and effective cleanup and decontamination. This
network became operational on March 9, 1970, when a central telephone
number (513) 961-4300 in Cincinnati, Ohio, was activated on a 24-hour basis.
Twelve member companies of the National Agricultural Chemical Association
(NACA) are cooperating in the program by furnishing personnel, equipment,
and expertise for the prompt and efficient cleanup and decontamination of
Class B poison pesticides involved in a major accident. More than forty
safety teams currently make up the national network, the operation of
which is outlined in the attached "Emergency Procedure for Handling Acci-
dental Spills of Class B Poison Pesticide Chemicals." The success of the
22
-------
network depends principally on (1) the rapid notification of such an acci-
dent by someone at the scene and (2) the rapidity with which isolation and
containment of the spills is achieved so that cleanup and decontamination
can proceed effectively. *• ' ^ The Safety Team Network has a voluntary
cooperative agreement with the American Truckers Association (ATA). There
are, however, no laws or regulations to enforce notification of such acci-
dents, and incidents have occurred where drivers were unable or unprepared
to hold trucks until the Safety Team Network had the opportunity to inspect
the site and take appropriate action. Although our survey did not discover
any reported transaction incidents, it seems very clear that the potential
for massive entry of pesticides into the water environment is very high
during transportation because of the volumes involved and the difficulties
of preventing migration into water resources.
The shipping destination from the manufacturer's plant or central
distributing warehouse (in some cases, cargoes are temporarily stored at
trucker's terminals) is one or more of the following points:
(a) Wholesaler or local distributor
(b) Vector control districts
(c) City, town or municipality
(d) Commercial applicators
(e) Retailers
When the products are received at (a) they are stored for further transfer
to another destination such as (b), (c), (d), or (e). In the case of
large volume users such as vector control districts and commercial applicators,
shipment may be direct from the manufacturer. Our contacts with distributors
did not uncover any admissions of losses due to breakage or leakage from
23
-------
cans, drums or bags. The explanation given most frequently was that the
present high cost of pesticides resulted in better packaging in small units
(5-gallon cans or 4-pound bags) to allow easier handling. Furthermore, the
containers themselves are more resistant to breakage than was the case with
low-cost products, e.g., DDT, where the low competitive prices for the
product precluded quality packaging. The results of our survey indicated
that the probability for entry of massive amounts of pesticides into the
water environment during their transportation from manufacturer to wholesale
distributor are no greater than any other hazardous polluting substance
being transported in commerce.
C. FINAL APPLICATION AND CONTAINER DISPOSAL
Once the pesticide has reached the organization or person
responsible for its final dispersal, its application and the disposal of
containers is to a large extent determined by the laws and regulations of
individual states. While applicators are primarily responsible for inten-
tional additions of pesticides to the environment, they must also be
considered for potential releases due to accidents in handling, preparing
and applying pesticides as well as the disposal of used containers, unused
products and equipment cleaning solutions. Our survey of pesticide
applicators indicated that recently issued regulations, which are more
stringent than older rules, are resulting in fewer but more proficient
applicators; those without broad knowledge of pesticides and their uses
often discontinue operations. For example, we estimate that within recent
years nearly 20% of New Hampshire's applicators have left the business,
primarily those not attuned to the broader aspects of pesticides as applied
to vector control. This indicates a trend toward upgrading the quality of
24
-------
commercial applicators, a very desirable step forward in assuring better
usage of pesticides.
During our field interviews we encountered difficulty in
getting straightforward answers to many of our questions regarding the
procedures for disposing of used containers, unused pesticides, and equip-
ment cleaning solutions. Although the states of Massachusetts, New Hampshire
and Maine have established specific regulations concerning the disposal of
containers on unused pesticides (see Table V-l for a summary of these
regulations), we could not confirm that these regulations are strictly ob-
served by the applicators or closely monitored by state regulatory agencies.
We received reports in Massachusetts that pesticide bags as well as crushed
containers and drums often are disposed of at town dumps, but we could not
determine whether these areas are officially designated by local Boards of
Health for disposal as required by Massachusetts law. Several commercial
pesticide applicators complained that many towns had no such areas, and any
disposal would be in technical violation. Burning of combustible containers,
and dilute solutions of pesticides in combustible solvents, in municipal
incinerators or other devices approved by the Board of Health is prescribed
in Massachusetts, Rhode Island and New Hampshire; however, we found no
indication of the relative frequency of incineration as compared with
burying. Furthermore, we were able to obtain only meager information con-
cerning the actual methods of disposing of equipment and container washings.
Although the rules and regulations in New Hampshire and Rhode Island are
quite clear in the procedures to be used, other states generally specify
only that these shall be disposed of by burial in a manner which will pre-
vent entry into the water environment.
25
-------
TABLE V-l
REGULATIONS IN NEW ENGLAND STATES CONCERNING DISPOSAL OF UNUSED PESTICIDES AND EMPTY CONTAINERS
!• Disposal Areas
2. Disposal Method
2a General Provisions
2b Liquid Combustible
MASSACHUSETTS
Municipal incinerator or other
place assigned by the local
Beard of Health
In auch a manner and at such
location that contamination of
minimized and that the material
will not be uncovered or other-
operations in the area. If
burled, pesticide shall be
covered with at least 18" of
compact cover material.
Other than organophosphate and
hormone type may be burned and
residues disposed according to
2a.
Burning is restricted to 2 days
a week and 1 gallon per time
under appropriate atmospheric
conditions' Organophosphate and
hormone type* treated as non-
combuatible.
NEW HAMPSHIRE
Municipal Incinerator
or approved disposal
•itt
Surplus or unused
pesticide shall be
disposed of by
burial in same man-
ner as Massachusetts.
MAINE
Stored in a safe plac
or buried: (1) on
the land of the appli
land of and with the
approval of other thai
the applicator pro-
be put in or close to
watering wells, open
springs or areas wher
material will flow
directly into water-
ings.
Burled with at least
18" of compacted
cover material.
VERMONT
z
o
IH
S<
3
3 8
H S
s
B? in
a S
W VI
M
^ JM
§ ^
tn Q
2 i
(J 04
G
C/l
a. w
a
" S
S *
M >
O J
S o
5* M
C/l )-*
>-l Ul
* 1
M
35 M
gp^
U
M 2
*" 3
s §
G S
CONNECTICUT
prohibited. No pesticide or con-
tainer therefore shall be discarded
lutlon of any waterway or endanger
plant and animal Ufa or the public
health and safety.
M O
U 1 0
8J B >
u o w
a « z
o u p- o
o S >. S
Z 0 -J -J
s S S a
| - a a
2 Q U W
5 U) M H
W» W O* <
3 « H
U. M
0 « H
w w in
o u »H afi
EU Q U
M O * 2
Q j-. w 5
U OT M o«S
BU < O
0. H C
RHODE ISLAND
only at approved refuse disposal
sites, in a municipal incinerator
or In a special incinerator which
meets. with the approval of the
, tlcides
shall be disposed of by burial
with at least 18 inches of
and at such a location vithin
the disposal area that contami-
nation of ground water is
prevented.
-------
TABLE V-l (Continued)
2b (continued)
Noa-conbustlble
2c Solid
Id Containers
*
3. RE-USE of Container*
MASSACHUSETTS
By burial In accordance with 2(a)
By burial In accordance with 2(a)
According to rule* and regula-
tion* eatabllahed by the Dept. of
Public Health.
Unless treated In conformity with
Public Health regulations, con-
tainers shall not be used for
storage of human or animal food or
water or for the storage of cook-
Ing utensils, dishes or clothing.
NEW HAMPSHIRE
NON-COMBUSTIBLE CON-
TAINERS USED IN
CONNECTION WITH ORCANO
PHOSPHATE COMPOUNDS:
Glass: breakage and
burial (18" deep)
Metal: rinsing, punch-
ing holes on top and
bottom, crushing and
burning. Rinsing sol-
ution should be buried
OTHER THAN THOSE USED
IN CONNECTION WITH
ORCANOPHOSPHATE COM-
POUNDS: Rinsing and
disposing of water by
burial
No pesticide container
shall be used for
storage of food, water
cooking utensils,
dishes or clothing.
No pesticide contain-
ers should be used for
any other purpose un-
less approved by the
Board of Health after
properly cleaned.
MAINE
If not returnable,
shall be perforated 01
-crushed and burled
with at leaat IB" of
compacted cover
material.
Return to manufacturer
If returnable, or sell
,to reconditioning
companies. All other
containers shall be
handled in accordance
with 2d.
VERMONT
CONNECTICUT
RHODE ISLAND
Organophosphate Containers
Class - Break and bury as In 2 (a).
Metals - Wash with caustic soda
snd detergent solution. Bury
rinse water as in 2(a).
Other Pesticide Containers
solvent. Dispose of rinses as in
2 (a).
and buried aa in 2 (a).
No pesticid container shall be used
for the sto age of human or ani.ir.al
food or wat r nor such containers be
used for th storage of cooking uten-
sils, dishe or clothing.
No pesticide containers shall be
used as dock or raft floats.
ta other purpose unless such purpose
las been approved by che Department
of Natural Resources after the con-
tainers have been properly cleaned.
-------
Other potential paths for entry of pesticides into the water
environment are through back-siphoning when tanks are filled from surface
waters and where inattention results in overflow of tanks. The practice
of siphoning water from surface supplies is forbidden in New Hampshire—an
excellent precautionary measure in our opinion.
In summary, although we have not yet documented specific
incidents where pesticides entered the water environment due to accidents
or poor disposal practices by the applicators, we also were unable to
ascertain any uniformity of control practices by regulatory agencies. Because
of the multiple handling, mixing, and transfer required of the applicators,
there is a potential for significant numbers of uncontrolled entries into
the water environment.
In our opinion, better procedures should be developed to help
reduce the potential for spills such as requiring all loading and unload-
ing of concentrated liquid pesticides be performed on impervious surfaces
in a curved area draining to a containment sump from which spilled materials
could be removed and treated for disposal. The disposal of spent containers
and unused pesticides should be monitored more closely, perhaps through an
accountability system such as numbering of containers and requiring return
to an authorized disposal site and specific disposal procedures established
for each pesticide. Although a number of legalistic schemes might be
developed for reducing the potential for spilled pesticides getting into
the water environment, the most desirable first step is an expanded educa-
tional program involving the applicators including, perhaps, a licensed
operators program such as employed for sewage treatment plant personnel.
27
-------
D. INTENTIONAL APPLICATIONS
The intentional application of pesticides for vector control
in the Northeastern United States utilizes all of the commonly accepted
methods of air, ground, and water application. Atomization of liquids for
application from air or ground-borne equipment has been the subject of
large numbers of studies to determine the most desirable droplet size ranges
and atmospheric conditions. These are two prime factors in affecting the
distribution of active materials, and minimize the drift of particulates into
unwanted areas. Akesson, et al. gave a succinct review of methods for
controlling spray atomization in aerial applications. Both air and water
routes of pesticides dispersion in the environment is discussed in the
January 1969 "Report to the President—Control of Agricultural Related
Pollution." Aerial application or ground application using foggers are the
most difficult to control precisely with respect to area covered. Both
methods could, conceivably, cause direct entry of pesticides into the water
environment, but only where direct spraying is carried out or where drift
occurs. In the Cape Cod area there are cranberry bogs which may inject
pesticides into "flooding" water, but provisions are made to hold the water
sufficiently long enough for deposition and degradation to occur, before
drainage to water courses is allowed. Of course, the he-"Ing time required
for complete degradation may be impossible in the case <-f some pesticides;
consequently, adsorption on soil particles and detritus with concomitant
slow release rates must be relied upon to minimize widespread dispersion
throughout the ecosphere.
The air route of pesticide application is dependent, obviously,
on the microclimatology effects at the site of application. Although elab-
[81
orate mathematical models exist for predicting the dispersion of aerosol
28
-------
from point and diffuse sources, the major criteria for the application of
pesticides is that calm wind conditions prevail and that temperature gradients
meet certain criteria. It is generally accepted^ that a normal lapse
condition (i.e., where temperature decreases with height) of about 0.1°F
should exist between the 8 and 32 foot elevations. The effect of wind
velocity on horizontal drift of an aerosol particle of a given diameter is
to increase the drift distance in virtually direct proportion to the wind
velocity. Consequently, careful consideration "• ^ must be given to the
optimum droplet size as well as atmospheric conditions for effective, safe
application.
In our surveys of the Cape Cod area we determined that ground
and helicopter spraying equipment is more common than fixed wing aircraft.
The use of helicopters is attributed primarily to the limited field size,
the wooded nature of the terrain, and the nearby location of a U.S. Air
Force Base. The direct application of pesticides onto water is practiced
only on cranberry bogs, where the technique of holdup of the water for a
specified period of time is practiced.
The generally sandy nature of the soils in the Cape Cod area
could be expected to have a lower adsorptive capacity than clayey soils
or, conversely a higher release rate by either desorption or, in the case
[12]
of the more volatile pesticides, by volatilization. Furthermore, only
the most persistent pesticides or their metabolites might be expected to
be found in the soil column at any appreciable depth. For example, we
f 131
were told that where chlordane has been applied to golf courses on
Cape Cod for control of Japanese beetles, chlordane content four inches
beneath the surface is in the range of 0.05 to 0.08 ppm and estimates of
deepest penetration are in the vicinity of three feet. Literature references
29
-------
describe laboratory studies which indicate that the transmigration rates
of such refractory pesticides as dieldrin may be extremely slow and in ex-
treme cases, as long as several hundred years per foot of soil. Obviously,
no generalization can be made because the adsorptive-desorptive properties
are so highly dependent upon the individual pesticide, its degradability
and the unique properties of the soil into which it is dispersed. Therefore,
the most pertinent information must rely upon analyses of samples recently
secured from the area and these are discussed in another section.
30
-------
BIBLIOGRAPHY
1. Control of Agriculture-Related Pollution, A Report to the President
(January 1969).
2. Goodier, J.L., et al., Spill Prevention Techniques for Hazardous
Polluting Substances—Report on Contract 14-12-927 to the Environ-
mental Protection Agency.
3. Wechsler, A.E., et al., Preliminary Report on Contract 14-12-950 to
the Environmental Protection Agency.
4. Dawson, G.W., et al., Control of Spillage of Hazardous Polluting
Substances—Report on Contract 14-12-866 to the Environmental
Protection Agency.
5. Garrett, S.T., Jour, of the Water Poll. Cont. Fed., 43,773 (1971).
6. Thompson, C.H., and P.R. Heitzenrater, "The EPA's Hazardous Material
Spill Program," Amer. Inst. of Chem. Engr. Workshop, Charleston,
W. Va., October 27-28, 1971.
7. Akesson, N.B., W. E. Yates and S.E. Wilce, "Controlling Spray
Atomization," Agrichemical Age, 110-13 (Dec. 1970).
8. Turner, D.B., "Workbook of Atmospheric Dispersion Estimates,"
Environmental Science Services Administration (1969).
9. Akesson, N.B., and W.E. Yates, "Problems Relating to Agricultural
Chemicals and Resulting Drift Residues," Annual Rev. Entomol.,
j), 285-318 (1964).
10. Mount, G.A. , "Optimum Droplet Size for Adult Mosquito Control with
Space Sprays or Aerosols of Insecticides," Mosquito News,
30, No. 1 (March 1970).
31
-------
11. Huang, Ju-Chang, "Effects of Selected Factors on Pesticide Sorption
and Desorption in the Aquatic Environment," Journ. Water Poll.
Cont. Fed., 43, No. 8, 1739-1749 (1971).
12. Quenzi, W.D. , and W.E. Beard, "Volatilization of Lindane and DDT from
Soils," Soil Sci. Soc. of Amer., Proceedings, _34, 443-447 (1970).
13. Personal Communication, Mr. Charles Adao, Otis Air Force Base, Cape
Cod, Massachusetts.
32
-------
VI. IMPACT ON THE ENVIRONMENT
A. DESCRIPTION OF STUDY AREA
1. Geographic and Hydrologic
Salt water marshes are land forms resulting from the invasion
of shallow water by land vegetation. They develop in those coastal areas
where land erosion and deposition of sediments have built up an intertidal
flat and where the shore is protected from the open sea by a bay or spit.
On Cape Cod, as along the entire glaciated East Coast, the marshes formed
on land scraped bare by the retreating ice, or on piles of debris left as
the glaciers Belted. Spartina alterniflora grass germinated in these areas
anchoring the soil and preventing further erosion. Once established, such
salt water cordgrass built up the marsh by accumulating salt marsh peat and
by acting as a trap for sediments brought seaward or carried shoreward by
the incoming tide.^
Each successive generation of marsh grass grows on the root stocks
and trapped sediments of the preceding generation causing the marsh to
increase in depth and to spread. At the same time, the deposition of
sediment continues, primarily by incoming tides, but also from inland runoff
carrying silt from the land, allowing cordgrass to become established further
out into the intertidal flats. On Cape Cod the Sandwich moraine stretches
from the Cape Cod Canal to Orleans at a height of 100 to 300 feet above sea
level. This mass of sand, clay and rock cleanly separates our two study
areas and the Bass Hole Marsh and Herring River Marsh receive entirely distinct
runoff water, although the two areas are within six miles of each other.
33
-------
The entire area has exceptionally good drainage and the soil a high infiltration
rate; rain water percolates through the sandy/gravely soil rather than running
off. The major difference between these two Cape Cod marshes and most other
salt water marshes is the low volume of fresh water and inland nutrients
resulting from runoff.
The moraine is largely uninhabited, and there is little waste to
the Bass Hole and Herring River Marshes; waste from areas of dense population
in general passes directly into Cape Cod Bay on the north or Nantucket Sound
on the south. Because of this pattern these two marshes are largely uncontam-
inated by industrial pollutants and domestic sewage. Agricultural wastes are
little in evidence; the major segments of Cape Cod agriculture have declined,
[2]
and only a few active cranberry bogs and nurseries remain. In general,
although there has been an increasing population pressure on Cape Cod, little
ecological change has resulted from the increased release of wastes and
marshes have generally retained their form.
The marshes under study are unusual in that the effect of surf is
negligible. The Herring River effectively separates its marsh from the sea,
T31
and a large permanent sand bay isolates Bass Hole. Water mixing in these
marshes is therefore almost entirely the result of tidal action and density
inversions.
The Herring River Marsh water system does interconnect with fresh
water ponds upstream of the area we studied. The Bass Hole Marsh area studied,
in contrast, has no contact with open bodies of fresh water. There is a
significant difference in the magnitude of the tides; in the Bass Hole Marsh
the mean range is approximately 9.5 feet, while at the mouth of the Herring
River there is a mean range of 3.7 feet.
-------
Water temperature also was another physical characteristic which
has an effect on the biota of the two marshes. Cape Cod Bay at the mouth of
the Bass Hole Marsh is cooled by the Arctic Current, but an extensive sand
bar allows little cold water to enter the area. In contrast, Nantucket Sound
is warmed by the Gulf Stream.
2. Biotic
General observations did not reveal major differences in speciation
of either plants or animals between the two study areas, although differences
in the distribution of fish are known. Sampling of water and taxonomic
classification of the contained biota was conducted to determine the extent
of large differences in the microflora and microfauna. Samples were taken
of the main streams, feederstreams and mosquito control ditches during the
ebb tide to obtain material derived from the marsh rather than from the sea
and in a manner designed to eliminate any bottom sediment. Formaldehyde was
used at proper concentrations to assure the successful preservation of both
[4 5]
plant and animal specimens. '
Microscopic examinations revealed that the water samples contained a
rather limited number of life forms. In order to statistically compare micro-
biota from the Bass Hole Marsh versus the Herring River Marsh, samples were
concentrated prior to observation. Ten ml of each sample were centrifuged
for one hour, the collected insoluble material was resuspended, and half of
the volume was placed on a slide. Four quandrants on each slide were observed
under a magnification of 264 X's. The location of sampling sites in our two
study areas is indicated in Figure VI-1.
35
-------
FIGURE VI - I
LOCATION OF SAMPLING SITES
36
-------
Two samples from the lower Herring River Marsh (12 and 16) and
two samples from the upper Bass Hole Marsh (33 and 34) exhibited only higher
plant debris and detritus with no organized life forms (visible at 60 X's
magnification). The plant debris found in all samples was presumed to originate
from Spartina grasses. Animal life forms, Crustacea and nematinea, were seen
only in one Herring River sample (number 11) and in two samples from the Bass
Hole Marsh (26 and 27). Other than these animals, the most commonly found
life forms were filamentous algae, (none blue-green) colonial algae,
diatoms (mostly Cymbella, a freshwater genus) and a dinoflagellate.
Based upon these samples, the two marshes appear to be nearly
identical in those microscopic organisms which reside at the base of the
food chain. Therefore, descriptions of much of the environmental relation-
ships in this report will apply to both areas, although specific exceptions,
especially in regard to fish life will be made.
3. Biodynamics
The primary chemical energy production in the marsh occurs in the vascular
plants which utilize radiant energy for photosynthetic food production. These
plants decompose slowly and enter the water as organic detritis which, together
with absorbed bateria, fungi, protozoa and algae, become the important food
source for most of the marsh animals.
The salt marsh and associated estuarine ecosystem is a highly productive
environment. It is richer in nutrients and has a higher annual production rate
r 01
than any other sea or land areas with the exception of cultivated areas.
It has been estimated that tidal marsh ecosystems produce approximately 3 tons/acre
of dry plant material per year, as a result of the nutrient cycle trap effect of
the estuaries. The most important factor in this effect is the binding
capacity of the fine sediments which allows them to contain large quantities of
-------
adsorbed nutrients, trace metals and other materials. There is also a
trapping effect caused by the vertical movement of water masses of different
salinities and hence densities and the favorable oscillating tidal currents.
Nutrients are added to the sediments by the decay of marsh as well as marine
organisms, and through the process of biodeposition in which filter feeding
molluscs and crustaceans remove large amounts of suspended particles from the
water and excrete fecal pellets or pseudofeces. These more concentrated organic
foodstuffs may be eaten by deposit feeding organisms or become part of the
nutrient store of the sediments. Once "trapped" and adsorbed by the
sediments nutrients are easily released for reuse by the primary producers.
The organic detritus in the sediments is decomposed by intensive microbial
activity which through the sulfur, nitrogen and phosphorus cycles release
usable ammonia, phosphate and nitrate from complex organic compounds. The
burrowing animals and filter feeders present in the marsh environment also
release nutrients from the sediments by bringing them to the surface.
The tides are very important in the nutrient cycles of the marsh.
Decomposition occurs where there is ample moisture and exposure to air. This
is both the source of detritus and a means of releasing much of the nitrogen,
phosphorus, and other plant nutrients which are then available for synthesis
into forms which plants can use. Unused nitrates and phosphates, however, also
move out with the tides and become a nutrient source for the bay plant life as
well as settling to the sediment bottom.
Water movements, as well as salinity changes play an important role
in determining what organisms live in any particular marsh as well as the
ri2i
distribution of those organisms! For example, the distribution of
mussel larvae may be determined by the magnitude of the tide at the time of
settling. Since they are filter-feeding animals, their rate of growth is
determined by the length of time they are covered by water and by the amount of
food brought to them by the tide.
38
-------
Relatively few plant and animal species are able to adapt to the
marsh environment. It is an area of extremes involving changes in salinity,
temperature, and desiccation. Those that have been able to adapt remain
relatively free of predators and competing species allowing them to occupy a
broader niche and to be more abundant than otherwise would be possible.
Of the limited number of life forms which have successfully adapted
to the salt marsh ecosystem, nearly half are terrestrial species, common through-
out the grassy areas and on higher ground. These species have made only
slight adaptation to the marsh ecosystem and are represented primarily by insects
and arachnids. Many of these insects live and feed directly on the Spartina,
eating either the tissues or the juices as well as using the plants for pro-
tection from the incoming tides. Others are mud dwelling and feed on detritus.
The birds comprise the major remaining segment of the terrestrial species, along
with a few racoons and rodents.
Of more importance to the energetics of the marsh are the estuarine
and aquatic marsh species. With the estuarine species are zooplankton such as
copepods and larval forms of invertebrate species such as shrimp, mussels,
annelids, crabs, snails, and clams, as well as most stages in the life cycles
of many species of fish. These animals primarily occupy the lower borders of
the marsh because they are not able to withstand exposure. Several species
of larger invertebrates live on the marsh surface and in the creeks. Many of
these are burrowers, using the mud to avoid exposure at low tide and as a constant
salinity and temperature source. Those that do not burrow usually maintain
shells which can be completely closed to avoid drying. Amphipods, blue crabs
and shrimp are found in the main stream; worms, oysters and mud snails are
found in ditches; ribbed mussels, periwinkles, fiddler crabs and marsh crabs
are representative of those animals found on the marsh surface. It is among
these larger invertebrates that one finds the animals of most importance to the
39
-------
energetics of the marsh ecosystem. Filter feeding animals such as the
mussels, clams, and polychaete worms remove large quantities of suspended
particles from the water consolidating the nutrients for use by such deposit
feeding marsh animals as the annelids, nematodes and periwinkles. It has
been estimated that a marsh area contains approximately 3,673,000 mussels per
acre each capable of pumping 1.2 gallons of water per hour, thereby
removing tremendous quantities of detritus and suspended nutrients. The
deposit feeders return the nutrients to the sediments where they remain
available for reutilization by the marsh ecosystem. Burrowing animals
(particularly crabs) rework the surface of the marsh at low tide and further
concentrate organic matter in their feces, thereby having a considerable
influence on other populations.
The primary producers available in the low marsh at low tide are
the mud algae, large algae and 5partina alterniflora. These together with
organic detritus form the first step of the food chain. The low marsh
consumers include amphipods or beach fleas, marsh crabs, fiddler crabs, green
crabs, marsh insects (who venture down to the intertidal area at low tide)
and periwinkles. Few secondary consumers (carnivores) are present in the
low marsh at low tide.
The primary producers in the high marsh at low tide are the large
algae andSpartina patens. These together with organic detritus are eaten
by the primary consumers which include periwinkles, marsh snails, beach fleas
and insects. Secondary consumers include spiders which feed on insects,
birds such as rails, crows and sandpipers which feed on periwinkles, snails
and beach fleas, and song birds which feed on insects.
-------
When the tide comes in the food chains of the marsh change.
Many animals decrease their activity at this time. Insects climb up or
into Spartina stems, birds retreat to their nests or higher ground, crabs
either climb plants (marsh crab), or burrow (fiddler crab) or become active
(mud crab, green crab and blue crab). Plankton is added by the tide as an
additional foodstuff to the first step in the food chain. Filter and deposit
feeders (mussels, barnacles, annelids and sand shrimp) increase their consumption.
Isopods, fish and invertebrate larvae are also swept into the marsh as a food
source for worms, shrimp, clams and crabs. Finally a new population of secondary
consumers, the larger fish, are introduced as top carnivores for whom most of
the marsh invertebrates function as a food source.
4. Species in the Cape Cod Marshes
a. Plants
The plants growing in the two Cape Cod salt marshes of our study
may be classified by their specific habitat; the lower border, the meadow,
the panne, and the upper border. The lower border of the marsh begins below
the point of mean low tide and includes the edge of the meadow which is highly
saline. Eelgrass (Zostera marina) grows below the low tide point where it
is continually covered with sea water. Above the mean low tide region salt
water cordgrass (Spartina alterniflora) dominates the edge of the meadow with
its mat of roots holding in place the underlying layer of peat and helping
to prevent extensive erosion of the marsh by wave action.
Beyond the salt water cordgrass region, the marsh opens out into
a relatively flat meadow which becomes flooded for a while at every high
tide. The saline concentration of the meadow is lower than that of the
lower border and consequently different plants inhabit this area. The
meadow comprises the major portion of every marsh, and salt meadow cordgrass
ina patens') is the most common and most important plant here.
41
-------
Frequently one encounters shallow depressions in the midst of
the meadow which are called pannes and contain water that is highly saline.
Arrow grass (Triglochinmaritirna), seaside plantain (Plantago oliganthos) ,
glassworts (Salicomia sp.)> sea lavender (Limaniwn nashii), saltmarsh aster
(Aster tenuifolius) and purple gerardia (Gerardia maritima) are all
halophytes which inhabit panne regions and which we have observed in our
study areas.
The upper border of the marsh begins at the mean high tide.
It accounts for only a small percentage of the total land area of a marsh but
is of significance in this study because it is where chemicals, if used, are
applied for mosquito control. The plants in this region cannot tolerate
much salt, and get flooded only during exceptionally high tides and storms.
The orach (Atriplex patulo), marsh mallow tfibiscus palustris") , saltwort
<§alsC(,a. kali), sea-blite (Suaeda sp.), seaside goldenrod ($ olidago satnpervirens)
switchgrass (Paniown virgatum"), spike grass (Distichlis spicata}, and common
reedgrass (Phragrrtites Gommunis) all inhabit the upper border. Black grass
(Jwious gerardi), a dark green rush, is very common in this region especially
in the Herring River Marsh, and shrubs such as the marsh elder (Iva frutese&ns)
and sea myrtle tree (B accharis halinrifolia) begin to invade the marsh at the
border. Poison ivy (JRhus radicans~) is frequently common at the edge of the
northern border, especially if the region has been disturbed by cultivation
as at Bass Hole.[13'14'15]
In a marsh there are also many plants, of lower phyla that cannot
be identified without a microscope. The purple sulfur bacteria for example
are anaerobic organisms which inhabit the oxygen free layer of mud just
below the surface. Numerous kinds of diatoms and algae are found in the debris
at the bottom. Filamentous species of blue green algae are especially
common. The totality of these unicellular and colonical organisms is usually
-------
referred to as phytoplankton. Although they are most important in the food
chain, it is our belief that a discussion of their tazonomic classification
does not contribute to an understanding of their role and has been omitted.
b. Animals
Just as the salt water marsh contains a variety of plant life,
classes of which find a distinct niche dependant upon the salinity and maximum
depth of water, so too, can distinct niches be allocated for the animal
population of the salt water marsh. One of these niches is inhabited by
fresh-water species, which live on the landward edge of the marsh. These
animals include the big green darner (Anax jimius), a high-flying species of
dragon fly which feeds on mosquitos and other flying insects as an adult
in the marsh but which as a nymph lives in fresh water. Such species will
not be enumerated here since this introduces a whole range of organisms and
food chains which are only of peripheral concern to the marsh ecosystem.
It is taken for granted that the marsh ecosystem and the fresh-water system
which borders it would have some relationship implicit in the concept of
natural interdependence.
A group of species which also have little inter-relationship with
the marsh life are those terrestrial species which do live in the marsh.
Many of these are insects such as the green-head fly (.Tdbanus), cinch bugs
(.Isohnodesmus) , or tumbling flower beatles (Mordellid). Other terrestrial
insects living in the marsh are specific species of grasshpper, plant hopper,
sand fly, and ants. Other invertebrates in this niche are worms such as
Chaetopsis aena and spiders such as Lycosa modesta. Among the vertebrates
are the sea-side sparrow (Ammospiza maritima) and the rice mouse (Oryzomys
palustris). Although many terrestrial species live their entire lifetime in
the marsh, because of their greater adaptability they usually evidence less
interaction with the true marsh ecosystem than species whose lives are more
directly related to the estua'rine water system and tidal pattern.
43
-------
TABLE VI-1
MAJOR ANIMALS OF THE CAPE COD INTERTIDAL BIOMASS*
Gem Shell (Gemma gemma)
Annelid (Streblospio benedioti)
Annelid (Lumbrineries tenuis)
Annelid (H eteronastus filiformis)
Metanemertean Worn//.mpfr£porws spJ
Spire Shell (Hydrobia mlnuta)
Ostracod ('Ostracoda spp.)
Blood Worm (Glycera dibranahiata)
Moon Shell (Polynioes duplioata)
Common Synapta (Leptosynapta inhaerens)
Heteronemertean Worm (Miarura leidyi)
Plumed Worm ('Diopatra cuprea)
Annelid (Saolopus fragilis)
Polychaete Worm (Eteone heteropoda)
Polycheate Worm (Pygospio elegans)
Bamooo Worm (CyImene1 la torquata)
Mud Snail ('Nassarius obsoletus)
* Animal species present at concentrations
of greater than Ig/m2 in Barnstable Harbor
in 1959 [18].
-------
TABLE VI-2
INVERTEBRATES COMMONLY FOUND IN CAPE COD MARSHES
MOLLUSCA
Duck Clam (Maooma balthioa)
False Angel Wing (Petrioola pholadiformis)
Oyster (Crassostrea virgin-Loo)
Razor Clam (Ensis direotus)
Channeled Whelk (Busycan oannaliaulatum)
Bay Scallop (Aquipeaten irradiccns)
Oyster Drill (Urosalpinx cinerea)
Ribbed Mussel (Modiolus demissus)
Periwinkle (Littorina littorea)
Blue Mussel (Mytilus edulis)
Quahog (Venus meraenaria)
Long-Neck Clam (Mya arenaria)
Marsh Periwinkle ('Littorina irrorata)
Land Snail (Melampus bidentatus)
ANNELIDA
Clamworm (Nereis virens)
Trumpet Worm (Cistenides gouldii)
Polychaete Worm (H arnothoe extenuata)
Polychaete Worm (Nephthys oiliata)
Blood Worm (Glyoera dibranahiata)
Plumed Worm (Diopatra ouprea)
NEMERTEA
Heteronemertean Worm (Cevebratulus lacteus)
SIPUNCULOIDEA
Sipunculoid worm ( Golfingia gouldii)
ARTHROPODA
Acorn Barnacle (B alanus irrrprovisus)
Spider Crab (Libinia sppj
Horseshoe Crab (Limulus polyphemus)
Lady Crab (Ovalipes ooellatus)
Green Crab (Carcinides iraenas)
Rock Crab dCanaer irrovatus)
Jonah Crab (Cancer borealis)
Fiddler Crab (Vca pugnax)
Mud Crab (Neopanope texa.no)
Blue Crab (Callineotes sapidus)
American Lobster (H omarus americanus)
Isopod (Cyathura polita)
Isopod (Idotea baltiaa)
Common Prawn ('Palaerr.onetes vulgaris)
Common Sand Shrimp (Crago septemspinosus)
Eel Grass Shrimp (H ippolyte zosterioola)
Opossum Shrimp (Mysis stenolepis)
AmphipodfAmphithoe rubricated
Amphipodf Amphiinoe longimana)
Marsh Crab (Sesarma retioulatunj
Plant Hopper (Prokelisia marginata)
Greenhead Fly (Tabanus nigrovittatus)
Sand Fly (Culicoides aanithoraa)
Carpenter Ant (Camponotus pylartes)
Salt Marsh Mosquito (Aedes solliaitans)
Monarch Butterfly (Danaus plexippus)
Luna Moth (Tropaea luna)
45
-------
A more detailed investigation can reveal enormous diversity of species in
the estuarine habitat. Thus 49 dif f erent Foraminipherans were found in
[22]
the lagoon and estuaries of Buzzards Bay on the south shore of Cape Cod.
Random sampling in Barnstable Harbor at the mouth of the Bass Hole Marsh of
risi
the intertidal fauna revealed 24 different annelids1 , and of the more than
1300 common invertebrate marine animals found in the shallow waters of the
North Atlantic Coast, 35 common species of ribbon worms can be found.
Omitted from Table VI-2 are those phyla with only minimal representation in
our study area such as the Coelentera which contributes the burrowing sea
anemone (Bduardsia") , the turbellarians of the Platyhelmia and the Echinoderms
such as the keyhole sand dollar (Mellita testudinata) .
Among the Arthropods especially, an enormous diversity of speciation
is found; enumerable different species live in the salt marshes of Cape Cod.
The same is true for ants, grasshoppers and spiders. The listing of a
single mosquito species is, of cours, also a simplification since it has
already been stated in this report that more than twenty species of mosquitoes
F231
of seven genuses have been found on Cape Cod. However, Aedes sollicitans
is able to tolerate the highest salinity within the marsh and, thus breeds more
out into the marsh itself rather than in the less saline water of the salt
marsh border,
To supplement our literature searches, a small beach seine was used
by the Division of Marine Fisheries, Department of Natural Resources, Common-
wealth of Massachusetts to sample the fish population at the mouth of the
Bass Hole Marsh. Those fish trapped in the seine included the four spine
stickleback, winter flounder fry (locally called blackbacks) , mummichog,
American eel and a small number of pipe fish. At this location, in addition,
cunner and silverside were observed and, by observation, it was estimated
that the mummichog represented the fish present in greatest density throughout
46
-------
TABLE VI-3.
FISH OF THE CAPE COD MARSHES
Blueback Herring (Alosa aestivalis)
Alewife (Alosa pseudoharengus)
Atlantic Menhaden (Brevoortia tyrannus)
Atlantic Herring (Clupea h. harengus)
American Eel (Anguilla rostrata)
Mummichog (Fundulus heteroalisus)
Striped Killifish (Fundulus majalis)
Atlantic Cod (Gadus morkua)
Atlantic Tomcod ( Microgadus tomcod)
Fourspine Stickleback (Apeltes quadracus)
Threespine Stickleback (Gasterosteus aculeatus)
Northern Pipefish (Syngnathus fusous)
Striped Bass ('Roccus saxatilis)
White Perch (Morone amerioana)
Bluefish (' Porriatomus saltatrix)
Mackerel Scad(Decapterus maoarellus)
Northern Kingfish (Mentiairrhus saxatilis)
Scup (S tenotorms chrysops)
Gunner (Tautogolabrus adspersus)
Tautog (' Tautoga onitus)
Atlantic Mackerel (S ooniber saombrus)
Northern Searobin (Prionotus aarolinus)
Striped Searobin (Prionotus evolans)
Grubby (Myoxocephalus aenus)
Longhorn Sculpin (Myoxocephalus ootodecemspinosus
Lumpfish (Cyclopterus lunrpus)
Tidewater Silverside (I'.enidia beryllinaJ
Atlantic Silverside (llsnidia menidia
Windowpane (S cophthalrrrus aquosus)
Winter Flounder (Pseudopleuronectes americanus)
Yellowtail Flounder (Limanda ferruginea)
Northern Puffer (3pheroides maculatus)
Ocean Sunfish (Mola mola)
Goosefish (Lophius ameriaanus)
Orange Filefish (Alutera schoepfi)
American Sand Lance (Ammodytes amerioanus)
Crevalle Jack (Caranx hippos)
Black Sea Bass (Centropristes striatus)
Sheepshead Minnow (Cypronodon variegatus)
Rainwater Killifish (Lucinia parva)
Planehead Filefish (Monaoanihus nispidus)
Striped Mullet (Mugil aephalus)
Oyster Toadfish (Ops anus tau)
Big-Eye Scad (Selar cnunenophtkalmus)
Lookdox>m (Selene vomer)
Atlantic Needlefish (S trongylura marina)
Hogchoker (Trineates raaulatus)
White Hake (Uropkyais tennis)
Sea THaven(H emitripterus amerioonus)
American Smelt (Osr.erus mordax)
Rock Gunnel (Pholis awinellus)
-------
the Bass Hole Marsh. The raummichog, as well as the cunner, are more
plentiful in the Bass Hole Marsh than the Herring River Marsh. In the Herring
River Marsh, one would expect to find a relatively high number of alewife,
striped killifish, scup, and Atlantic silverside. The distribution of
fish in each marsh varies with time of year, stage of development and tide
level. For instance, the large predator species move into the marsh only
with the tide and then only when they are in the region. Striped bass,
for instance, would be in the marsh from June to October as they come to
Cape Cod along their migratory route. The same would apply for menhaden,
but the marsh would also serve as a continual forage area for the young fish
of this species. Mackerel, herring, sea herring, and dog fish
would be found at the mouth of the marsh only.
The American eel, winter flounder, and alewife use the marsh at
quite distinctive times in their developmental cycle. Thus the anadromous
alewife use the Herring River as a major run. They spawn in the inland
lakes, with the adults arriving there in late April. The juveniles descend
into the salt marsh from July until the fall. Flounder spawn in the marsh
and the young-of-the-year live there. By the second year of age these fish
will only be found at the mouth of the marsh. The American eel by contrast
spawns in salt water and arrives at one or two years of age with the female
going up into the fresh-water ponds and the male staying in the lower marsh.
They remain for several years before returning to the sea.
The blue fish or snapper is like the sea bass, except it is more
[24]
prevalent on the south side of the Cape: This is a transient species
which also makes a summer run and will not enter into areas of decreased
salinity in the marsh. Pipe fish are to be found the year round.
48
-------
A complete listing of those fish species which have been observed
in the salt marshes of Cape Cod is presented in Table VI-3. This
Table does not indicate those fish for which only a single sighting was
made such as the twospine stickleback at the Herring River or the haddock at
the Bass Hole Marsh. The distribution of the fish between the Bass Hole
Marsh and the Herring River is noted with attention drawn to the most common
fish species.
The vertebrate class Chondrichthyes is represented by the skates
(Raja erinaoea and Raja ocellata) and smooth dogfish (tfustelus can-is) at
the mouths of both of the Marshes. Representation by the Amphibia and
Reptilia is not significant in the Cape Cod Marshes with only an occasional
fresh-water turtle, snake, or frog making an appearance in the marsh.
A large number of bird species, however, are found in the Cape Cod marshes.
A total of 384 species (including those now extinct or exterminated) have been
[25]
reported for the entire Cape. Sixty-eight bird species have been reported
[13]
in Connecticut tidal marshes.
F261
Table VI-4 includes those birds most commonly found in the marshes.
No listing has been made of those species rarely observed such as the Osprey,
King Rail and Black-Crowned Night Heron which are commonly associated with
the estuarine habitat. A separate table has been prepared, however, Table VI-5,
of those bird species of lesser occurence (between rare and common) but
which are familar to the amateur ornithologist.
Mammals do not form an important part of the Bass Hole Marsh or
Herring River Marsh ecosystem. Most come from the surrounding forest, such as
the squirrels and carnivores. The little brown bat (.Myotis leuoifugus') does
use the marsh as a feeding ground but does not live there. The moles, woodchuck,
and field mouse enter that portion of the marsh which does not get flooded.
49
-------
TABLE VI-4
BIRDS COMMONLY FOUND IN CAPE COD MARSHES
SUMMER RESIDENTS
Great Horned Owl (Bubo virginianus)
Red-Tailed Hawk (Buteo jamicensis)
Sparrow Hawk (Fatoo sparverius)
Herring Gull (LOTUS argentatus)
Great Black-Backed Gull (Larus marinus)
Crow (Corvus brachyrhynchos)
Blue Jay ( Cyanocitto. cristata)
Robin (Turdus migratorius)
Starling (S turnus vulgaris)
Bob-White Quail (Colinus virginianus)
Ring-Necked Pheasant (Phasianus colahicus)
WINTER RESIDENTS
Black Duck (Anas rubripes)
Goldeneye (Bucephala alangula)
Merganser (Fergus merganser)
Junco (Junco hyemalis)
Goldfinch (Spirus tristis)
Meadowlark (Stumella magna)
Bufflehead (Bucephala albeola)
MIGRANTS
Greater Scaup (Ay thy a marila)
Marsh Hawk (Circus ayar.eus)
Great Blue Heron (Ardea herodias)
Semipalmated Sandpiper ('Ereunetes pusillus)
Laughing Gull (Larus at-rioilla)
Arctic Tern (Sterna paradisaea)
Coot (Fulica ameriaana)
Wood Duck (Aix sponset)
Green Teal (Anas carolinensis)
Blue Teal (Anas discors)
Flicker ('Colaptes auratus)
Downy Woodpecker (Dendrooopos pubescens)
Song Sparrow (Melospiza melodia)
Crackle (Quisoalus quisaula)
Mourning Dove (Zenaidura maaroura)
Barn Swallow (Hirundo rust-Lao)
Semipalmated Plover (Ckaradrius serrripalrratus)
Piping PloverfCharadri-us rr.elodus)
Black-Bellied Plover (S quatarola squatarola)
Whimbrel (T.ur-.enius phaeopus)
Greater Yellowlegs (Totar.us melanoZeucus)
Tree Swallow (Iridoprocne bicolor)
Savannah Sparrow (Passerculus sa>~.d^ichensi.-s)
Snow Bunting (Pleotropher.ax nivalis)
50
-------
TABLE VI-5
OTHER BIRDS FOUND IN THE CAPE COD MARSHES
Screech Owl ( Otus asio)
Saw-Whet Owl (Aegolius acadicus)
Duck HawkfFaZeo aolumbarius)
Pigeon Hawk (Botaurus lentiginosus)
Bittern (Botaurus lentiginosus)
Clapper Rail (Rallus longirostris)
Woodcock (Philohela minor)
Common Snipe (C
-------
The rest of the species within the marshes our study area can
be subdivided by their relationship to the water. Thus there are estuarine
species limited to the low-water level such as the hydrozoan ($ ouganvillia) ,
and razor clam (Tagelus plebeius); and estuarine species which live in the
stream side marsh such as the blue crab (Callinectes sapidus) . Estuarine
species also occur well into the marsh including the annelid worm (Neanthes
suooinea) . Aquatic species with planktonic larvae like the ribbed mussel
(Modiolus demissus) and aquatic species living their lives entirely within
our study areas as the isopod (Cyathur otxpinata) must also be classified as
true marsh species.
Of considerable importance in the marsh in terms of numbers are
microscopic animals such as protozoans, the trochophore larval forms of
invertebrates, and the round worms found among the zooplankton. However,
because of observation and classification difficulties in providing a dis-
cussion of those particular species found in the two study areas in the
Cape Cod marshes and the complexity of their population dynamics , these
microscopic animals have been largely omitted in the current discussion of
the animal inhabitants of these marsh areas. They will only be discussed in
relation to ecological interactions, important toxicological considerations,
specialized roles in the food chain and rapid turnover.
[18]
Sanders has indicated that the major elements of the biomass
in the Bass Hole environs are the fifteen invertebrate species listed in
Table VI-1, but there are hundreds of other species of invertebrates which
inhabit the salt-water marshes of Cape Cod. Table VI-2 presents a sampling
C19 20 21]
of these lower life forms1 ' ' ; note that other names may be used for
some species. For example, the reader must make the association between the
quahog, Venus mercenariat Meroenaria mercenoria, round clam, hard-shell ^lam,
little neck clam, cherrystone clam and all other names invented for the same organ
52
-------
The only animals that can be called true residents are the muskrat
(Ondatra zibethioa"), meadow vole (Microtus pennsylvaniaus), white-
footed mouse (Peromysous leucopus) and the racoon (Procyon lotor) .
5. Food Chains
Within the salt marsh itself, the feeding patterns are not entirely
cyclic. Many of the predators are migratory and both birds and fish remove
energy from the salt water marsh and contribute it to ecosystems in other
locations. The loss of energy is more than made up for by the solar energy
absorbed by the plants and the nutrients entrapped as a result of the tidal
movement s.
As in most ecosystems the plants form the basis of the food chains
but the salt-water marsh is distinctive in the extent to which a large
portion of the food chain is dependent upon the initial consumption of detritus.
Only the insects, the blue crabs and the occasional mammals feed directly
on the Spartina grass and this at a low level. It has been calculated that
in a Georgia salt marsh less than 5% of the energy in the Spartina is consumbed
by insects. The majority of the energy in this grass serves as an energy
source in the form of detritus which, coupled with algae, is food for the
bacteria, crabs, worms, and other filter feeders. The crabs and nematodes
consume over 10% of the energy available to them1 Phytoplankton release
[27]
organic materials into the marsh and also serve directly as foodstuffs.
The marsh crab consumes the cord grass directly and its fecal
pellets contain nutrients which other animals can make use of. The fiddler
crab feeds on detritus and on algae in the mud. Although not a filter
feeder, this crab carries mud to his mouth where fine bristles screen out
the nutrient material and leave the reduced mineral content behind. The
fecal pellets of the fiddler crab also provide a more concentrated foodstuff
53
-------
which can then be consumed by worms and molluscs. However, 90% of the solar
energy trapped by the Spartina and algae is removed from the land and enters
fi9]
the marsh water system:
While it would be excessive to describe in detail those specific
T281
species which live on the microscopic aqueous flora and fauna of the marsh ,
it is important to realize the diversity of organisms which depend upon this
mixture of diatoms and algae. In addition to the mussels already mentioned,
the majority of molluscs are also filter feeders. Thus, spire shells and
Tellina agilis feed on diatoms and Aligena elevata on algae. The dinemertineans,
Amphiporus and Cerebratulus lacteus feed on similar microscopic food sources
with the latter supplementing its diet with the aforementioned spire shell as
well as Odostonria^ annelids and the larvae of mussles. Other ribbon worms also
consume polychaete annelids as evidenced by the setae found in their stomach
contents.
Most of the annelids consume diatoms with additional consumption of
nematodes by 5pic? setosa, other polychaete worms by blood worms, detritus by
members of the 5ootopos genus, Eteone andAmphitrite ozmata, gem shell larvae
by the clam worm, and crustaceans by the plumed worm. The spire shell is
also consumed by the common synapta (pynapta inhaereus) which is an echinoderm.
Diatoms, algae and detritus are consumed by such arthropods as C.areinoganrnarus
micfonotus3 Eupagarus longiearpus> and the crabs previously mentioned. This
diet is supplied by polycheate worms in Edotea montosa and with gem shells,
nematodes and other Crustacea in the common shrimp. The crustaceans as well
as the other invertebrates are consumed mainly by fish. Fish also eat insects
in the marsh. The sheepshead minnow, for instance, feeds on mosquito larvae.
The herring consumes many invertebrates, but at early stages in its life may
be consumed by jellyfish and predatory worms. •*
-------
Fish of the small size of the minnow, mummichog and silverside
furnish food for the predatory species. While some predators, like the
alewife which travels through the Herring River marsh, do forage in the
marsh channels, many of them only enter the lower reaches of the marsh with
the incoming tide. However, since the flow of energy is toward the sea,
the marsh provides an especially rich source of organic foodstuffs, important
to the growth of such carnivorous fish.
Amoung the birds commonly found in the Cape Cod marshes, the herring
gull and great black-backed gull are primarily carnivorous in their feeding
habits. The great blue heron feeds on fish as does the greater yellow legs
and the greater scaup. The latter also consumes crabs. Black duck feed
on intertidal animals as well as plants and seeds. The whimbrel feeds on
fiddler crabs. Also feeding on Crustacea and other mudflat animals are the
semipalmated plover, piping plover, black-bellied plover, golden eye, and
crow. A number of birds feed on seeds and insects in the marsh; the raptorial
birds on rodents.
B. TOXICITY OF PESTICIDES
To determine the impact of the vectoricide pollution on the water
environment we researched the literature for data relevant to the toxicity
pesticides. Using data obtained with different animal species, it is then
possible to postulate the effects which would be obtained on the distinct
species found in our Cape Cod study areas. Acute effects are those which
are experienced immediately (within 96 hours of exposure), while chronic
effects are those seen upon extended exposure to a particular toxic compound.
Carcinogenicity, mutagenicity, and teratogenicity are measures of quite
specific toxic behavior which are not of great importance in relation to
55
-------
wildlife (but are of extreme concern insofar as man is concerned). Finally,
sublethal concentrations of pesticides can produce biochemical and physio-
logical effects which may be of importance.
1. Acute and Chronic Toxicity
Tables VI-6 to VI-10 present the pertinent data which indicate
the lethal potential of the compounds Abate, DDT, Malathion, and Flit MLO.
Additional data is also presented in Table VI-7 on the toxicity of decompo-
siton products of DDT which have been found to be important in the environment
because of their persistence. We have not included data which we do not
believe to be relevant to our study area; e.g., the findings which have
been obtained with the coturnix quail have been left out of these tables since
this species does not inhabit our study area, and data relating to rainbow
trout and other fresh water fish has been eliminated in those cases where a
knowledge of the toxicity to saltwater species was available. Data relating
to the toxicity of compounds to man has been left out since it must be obtained
randomly and not from controlled experiments, and does not give a true indica-
tion of the toxicity of compounds. Information on the effects in man of
various compounds mentioned (except Flit MLO can be obtained from our previous
publication on "Organic Chemical Pollution of Freshwater."
2. Carcinogenicity, Teratogenicity and Mutagenicity
Extensive work has been done on the carcinogenicity of DDT.
Positive results have been found in the trout^ •* and rat: The production
of tumors in mice was attained with lower concentrations of DDT than in any
other species. Five generations of mice were fed DDT at 3 ppm of the diet
for 6 months. One-third of these animals developed tumors. DDT has also
been found to produce C-mitosis (chromosome breaks) when administered as a
saturated solution to plants. Such mitotic chromosome breaks can be an
indication of the mutagenicity of a compound. However, when fed to mice at
56
-------
TABLE VI-6
ACUTE AND CHRONIC TOXICITY OF ABATE
REFERENCE
30
31
32
31
33
30
34
35
SPECIES
Mosquito Larvae
Juvenile Shrimp
Amphipod
Juvenile Killifish
Bullfrog
Mallard duck
Mouse
Rabbit
CONCENTRATION
0.4-11 ppb
0.020 ppm
1.0-1.5 ppm
1 ppm
>2000 mg/kg
1200 ppm
4000 mg/kg
10 mg/kg/day
EFFECT
LC 50
EC 50
LC 50
No effect
LD 50
LD 50
LD 50
Minor liver
damage and
necrosis
Effects are statistically calculated values for observations
to be expected with an infinite population.
EC 50 = Concentration at which 50% of animals
should show an effert
LC 50 = Concentration lethal to 50% of animals
TLm = Approximate equivalent of LC ^Q
LD 50 = Dose lethal to 50% of animals
57
-------
TABLE VI-7
ACUTE TOXICITY OF DDT AND METABOLITES
REFERENCES
30
32
31
36
32
31
37
38
38
39
38
38
38
33
33
40
41
39
36
32
42
32
SPECIES
Mosquito
Amphipod
Juvenile Shrimp
Adult Shrimp
Hermit Crab
Juvenile Killifish
Sheepshead Minnow
Catfish
Carp
Fathead Minnow
Minnow
Guppy
Perch
Bullfrog
Mallard Duck
Mouse
Mouse
White Rat
Shrimp
Amphipod
Rat
Rat
CONCENTRATION
EFFECT
12 ppb
2-4 ppb
0.6 ppb
5.5 ppb
7 ppb
3 ppb
6 ppb
16 ppb
10 ppb
32 ppb
19 ppb
43 ppb
9 ppb
>2000 mg/kg
>2240 mg/kg
150 mg/kg
580 mg/kg
113 mg/kg
52 ppb DDE
2-6 ppb DDD
1060 mg/kg DDE
3400 mg/kg DDD
LC 50
LC 50
EC 50
EC 50
LC 50
LC 50
LC 50
TLm
TLm
TLm
TLm
TLm
TLm
LD 50
LD 50
LD 50
LD 50
LD 50
LC 50
LC 50
LD 50
LD 50
58
-------
TABLE VI-8
CHRONIC TOXICITY OF DDT
REFERENCE SPECIES
46
47
48
42
41
49
Pigeon
Mouse
Neonate Rat
Rat
Rat
Mallard Duck
CONCENTRATION
40 mg/kg
0.4-0.7 mg/kg
for 5 generations
1 mg
500 ppm
0.05 mg/kg daily
for 6 months
10 ppm DDE
EFFECT
Increased estradiol
metabolism by liver
homogenates
Leucocytosis
Significantly advanced
puberty
Stimularion of hepatic
microsomal enzyme
Histological changes in
liver, kidneys, myocardium,
suprarenals and brain
Decrease in reproduction
59
-------
TABLE V.I-9
ACUTE TOXICITY OF MALATHION
REFERENCES SPECIES CONCENTRATION EFFECT
30 Mosquito 90 ppm LC 50
32 Amphipod 2-4 ppb LC 50
32 Hermit Crab 0.1 ppm LC 50
38 Minnow 8.7 ppm TL 50
37 Sheepshead Minnow 0.3 ppm LC 50
50 Fathead Minnow 9 ppm TLm
51 Guppy 0.84 ppm TLm
38 Carp 6.6 ppm TL 50
39 Catfish 9 ppm TL 50
38 Perch 0.3 ppm TL 50
33 Mallard Duck 1485 mg/kg LD 50
51 White Rat 1375 mg/kg LD 50
60
-------
TABLE VI-10
ACUTE TOXICITY OF FLIT MLO
REFERENCES
52
53
54
54
54
54
54
54
55
SPECIES
Mosquito Larvae
Mosquito Larvae
Grass Shrimp
Fiddler Crab
Mummichog
Bluegill
Longnose Killifish
Domestic Duck
Rat
CONCENTRATION
0.5 gal/acre
1 gal/acre
8 gal/acre
8 gal/acre
8 gal/acre
>40 gal/acre
30 gal/acre
10,000 ppm
>10 g/kg
EFFECT
LD 50
LD 90
No effect
No effect
No effect
MTL
No effect
No effect
LD 50
61
-------
105 mg/kg, DDT was not mutagenic. DDT was also negative insofar as
teratogenicity (the ability to produce congenital malformations when administered
to t'ue pregnant animal) in both the mouse and the chick. Tests for
the toxic activity of DDT metabolites have also been made. ODD has been found
:este<
[60]
to be negative for carcinogenicity when tested in the mouse: It is also
negative in the mouse for teratogenicity.
The organo-phosphate insecticides have also been tested for their
teratogenicity. In the ewe, Abate has been found to be negative for such
[65]
effects. However, malathion was injected into chick eggs at 75 ppm per day;
congenital malformations were observed indicating a teratogenic potential.
No evidence for carcinogenetic potential has been found. Malathion fed to rats
at 5000 ppm in their diet for two years gave a negative result insofar as the
induction of tumors is concerned.
3. Sublethal Effects
Sublethal effects are defined here as any adverse response, except
death, due to insecticide application and/or accumulation in the biota. The
majority of the literature concerning sublethal effects for the four insect-
icides under consideration deals with the DDT family of compounds, mainly
because they are persistent in nature and can therefore be traced. The most
notorious sublethal effect proposed for DDT is the current theory explaining
the decrease in the populations of raptorial birds. These birds of prey are
at the top of numerous food chains. Insecticide residues, especially
chlorinated hydrocarbons, accumulate in these birds. The DDT residues may be
stored in fatty tissues for long periods without conspicuous effects. In
birds,, fat reserves are then utilized during migration and reproduction! ^
Apparently, the presence of DDT stimulates the liver to form metabolizing
enzymes which can act upon a variety of substances including the sex hormones
which regulate the reproductive cycle: ' '
62
-------
The decreased populations of these birds may be due to many factors:
1) delayed breeding or failure to lay eggs;
2) thinning of egg shells leading to much breakage;
3) eating of broken eggs by parents;
4) failure to produce more eggs after earlier clutches were lost;
5) high mortality of embryos and fledglings
A direct correlation has been proposed between the thinning of
raptorial bird egg shells and the presence of chlorinated hydrocarbon insecticides.
Calcium is deposited around an egg in the last 20 hours before laying. In birds,
calcium metabolism is intimately related to reproductive metabolism and is
[73]
controlled by estrogen and parathyroid hormone. Ratcliffe studied the
incidence of broken eggs in the nests of sparrowhawks in England and suggested
a cause and effect linkage between increased egg breakage, decreased egg weight,
and exposure to persistent organic pesticides in the environment for the species
examined. The reason that this type of sublethal toxicity is especially
insidious is that concentrations of pesticide residues found -in vivo are often
quite low compared with a toxic dose.
Species of birds which have not yet shown a population decrease may
yet be in danger. Prairie falcon populations in North Aaerica have not
decreased as have the peregrine falcons, but investigators predict that these
birds will exhibit reduced reproduction due to eggshell thinning and related
reasons. An inverse relationship has been established between eggshell thickness
and levels of DDE in their eggs. Wurster and Wingate have pointed out
that the susceptibility to chlorinated hydrocarbons varies considerably with
different species of raptorial birds. These authors believe that aggressive
behavior, increased nervousness, chipped eggshells, increased egg breakage,
and egg eating by parent birds suggest symptoms of hormonal disturbance or a
calcium deficiency or both.
63
-------
DDT also exhibits other sublethal effects. It interferes with
normal calcification of the arthropod nerve axon, causing hyperactivity
of the nerve and producing symptoms similar to those resulting from calcium
deficiency: ^ The DDT metabolites, DDD and DDE, have been found to affect
the steroid metabolism of rats. It has also been found that DDT disrupts
f 781
osmoregulatory events in the intestine of sea water-adapted eels. The
eel avoids desiccation by consuming sea water and excreting ions through the
gills. Adenosine triphosphatase enzymes are involved in the transport of
sodium ions and apparently DDT impairs water absorption by inhibiting these
enzymes.
The biochemical poisoning by sublethal amounts of DDT in other
f 791
fish has also been investigated. Mayhew1 J described the symptoms of DDT
poisoning in trout as marked irritability and sensitivity to vibrations, followed
by a loss of equilibrium with muscular spasms and convulsion. The loss of
coordination and other erratic behavior would seriously interfere with the
ability of fish to get food. Goldfish exposed to a 1 ppm solution of DDT
exhibited complete loss of balance. EEC activity of exposed cerebellum
tissue was then recorded. There was an increase in the amplitude and decrease
in the frequency of the spontaneous electrical activity of the cerebellum.
Finally, in experiments on the effect of DDT on the propellertail reflex,
trout learned to exhibit this reflex with electric shock as an unconditioned
stimulus and light as a conditioned stimulus. After a 24 hour exposure to
20 ppb DDT, 50% of the fish could not be conditioned at all, and the rest required
F811
significantly more trials than did the untreated control fish.
It would appear that the principal site of action of DDT in the
vertebrate organism is the central nervous system. The organophosphate
insecticides like malathion and Abate can also effect motor responses since
they act at the site of the nerve muscle junction. By inhibition of the
64
-------
enzyme acetylcholinesterase in the nervous system these compounds depress
or inhibit the transmission of nerve impulses. Abate produces a 70% inhibition
of blood acetylcholinesterase when administered in the diet of rats at
200 ppm. Malathion has been reported to produce a 65% inhibition of the
enzyme within 24 hours of placing a goldfish in 0.1 mg/1 of the organophosphate
:, in!
183]
F821
insecticide. In the rat, inhibition of acetylcholinesterase activity in
the brain has been observed.
In non-vertebrates other effects are observed. Abate at 10 ppb
in sea water causes a loss of equilibrium in juvenile shrimp. A concen-
tration of 170 ppb causes a 50% decrease in oyster shell growth. The minimum
f 851
threshold level affecting oyster shell growth was found to be 100 ppb. J
The protozoan ciliate, Tetrdhymena pyriformis, is reduced in population by
somewhat higher concentrations of DDT in its culture. Finally, sublethal
effects can also be observed in plants. Concentrations of between 1 and 100 ppb
of DDT reduced the photosynthetic activity of cultures of diatoms, green
f 861
algae and dinoflagellates.
4. Extrapolation of Laboratory Results
The most important consideration in utilizing laboratory toxicity
data for the estimation of the potential impact of these materials in the
particular marsh environment or the environment at large, is that of making
use of a limited number of toxicity determinations to an infinitely variable
biological system. Thus, in the literature very little is available
concerning the effect of insecticides or their toxicity to plants. One assumes
that the low level of organic material in pesticides would not compromise
the macroflora of an environment. However, in the estaurine environment present
in the salt water marshes under study, the algal population is of great importance
65
-------
in both initially trapping energy by photosynthesis and in providing a
major foodstuff for both filter and deposit feeders. Thus the phototoxic
effects of a pesticide might be of great significance in evaluating its impact.
It was necessary in the preceding section to provide listings of
the effects observed in many different species with each agent because the
toxicological sciences have not arrived at a point where predictions can be made
based upon examining a few model species. One extrapolates the toxic effect of
a material from its effect on related organisms. Differential toxicity is common,
For instance, it is well known that malathion is converted to the more toxic
malaoxon more rapidly in insects than in mammals. This provides a safety factor
in the use of malathion in normal agricultural insect extermination. In the
salt marsh ecosystem, however, one must be especially concerned with a compound which
has demonstrated a profound toxicity for invertebrate species.
Another difficulty in making extrapolations to an ecosystem is our
general lack of knowledge of the multiple interactions involved. The salt marsh
estuarine environment has been studied in significant detail insofar as
multiple food chains and environmental niches which exist. These have already
been discussed. However, one must always be concerned with the possibility
that quite specific food chains or sensitive species which may be of importance
can be missed in such an overview concerned mainly with the predominant species
and the movement of the majority of chemical energy from sunlight to higher
organisms and secondary consumers.
When toxicity testing is performed in the laboratory, pure compounds
are utilized, and the absence of interfering substances assured. However,
within the aquatic marsh ecosystem such is not the case. The water is a soup
of diverse biochemicals and chemical interactions can be expected. Even if
one were to catalogue the various materials present in the marsh it would not
allow one to draw firm conclusions as to synergistic or interactive effects.
66
-------
The Importance of molecular interactions both in the environment and
in vivo have only just begun to be investigated. ^
The adequacy of the laboratory research must also be open to
question. Many insecticidal materials have been measured for their toxic
effect against fish at concentrations in which they are insoluble. Also,
experiments have been performed in which it has later been found that most of
the material has adsorbed to the containder in which the experiment was
conducted. Analytical accuracy in relating concentrations of material to
toxic effects observed may also be open to question. For instance, it
is impossible in a study such as this to be sure that all data collected
implicating DDT has in fact been obtained with this compound and not with
polychlorinated biphenyls.
In nature, many compounds of low solubility will adsorb to the
F881
surface of detritus, mud and living plants. As such, these adsorbed
materials represent a new chemical species which was not investigated in the
laboratory. Thus, how can one extrapolate to determine at what concentration
an aquatic organism would be poisoned by a material present in solution as
opposed to that same material present in an absorbed state? Would the toxicity
be higher or lower in the latter case? Also, at what rate would the compound
disassociate from the adsorbed state? In most cases such questions have not
been answered but are of crucial concern where filter feeders and deposit feeders
are concerned as in the estuarine environments which we are studying here.
C. IMPACT OF VECTORICIDES ON THE ESIUARINE ENVIRONMENT
Pesticides are applied to the marshes of Cape Cod by direct and
localized hand spraying of bodies of stagnant water found to contain larvae.
These bodies of water may be either pannes, upper channels' (little influenced
by the tidal motion of water), or low areas at the very border of the marsh
which receive water during the monthly spring tide and in which such water
67
-------
remains unaffected by subsequent tidal movement. Concern with the movement
of pesticides from the surface of grasses to primary consumers can be
eliminated. Rather, our interest insofar as the initial distribution of the
pesticide in relation to the biota of the marsh can be directed wholely towards
the aquatic environment.
Solubility alters the immediate distribution of a particular pesticide.
Compounds with water solubility such as Abate will disperse throughout the
aquatic pool or channel. However, DDT can be expected to adsorb onto the surface
of algae, detritus, and mud. Suspending agents have an effect on distribution.
The rate of disappearance of compound, whether by hydrolysis,
reversible adsorption, vaporization, or other degradation is of great importance
in determining toxicity. The half-life of the toxic structure in the environment
is quite as important as its toxicity, since most toxic materials can be shown to have
their effect in proportion to exposure, usually expressed as concentration times
time (Cxt). A compound with a short half-life like malathion will exert its effect
acutely, whereas a compound such as DDT with an exceptionally long half-life can
be found to have subtle chronic effects. Relatively few controlled studies of
pesticide duration have been performed in salt marshes.
Malathion, applied to soil at 3 parts per million, was found in a
T891
concentration in the soil of a tenth part per million after 8 days. However,
silt loam soil was involved in the study and would be expected to provide a less
destructive environment to malathion than an aqueous environment with its
assoicated organic muds and microorganisms. DDT, by contrast, applied to a
highly organic forest soil at the rate of 1 Ib. per acre has been estimated
by Diamond et at, to persist for 30 years. More directly relevant to our study
area are the residues of DDT found in a Long Island marsh where the DDT in the
[32]
water was estimated at 0.05 ppb. In a Florida salt marsh treated with 0.2
Ibs per acre of DDT, the water was found to contain from 0.3 to 0.4 ppm and the sedi-
F911
ment as high as 3.5 ppm.1 J
68
-------
Although some persistence is found among the organophosphate insecticides,
it should be noted that these compounds are rapidly hydrolyzed in water and
persist only when adsorbed to insolubles. It would be expected that Abate and
malathion would have broken down to relatively non-toxic compounds prior to
their reaching the mouth of the marsh either as dissolved organic materials
or incorporated into the substance of food organisms. Actual physical transport
of toxic compounds in the marsh is probably related more to the movement of
persistent compounds through the food chain than the flow characteristics of
the marsh water system.
Much of the data on the movement of specific pesticides in food
chains will be covered in the next section in which the observed environmental
effects of pesticides have been reported. However, to introduce this subject,
an understanding of the ability of organisms to significantly concentrate
pesticides is of utmost importance. A summary of this data is found in the
government publication from the Office of Science and Technology, entitled,
F321
"Ecological Effect of Pesticides on Non-Target Species."1 While this
publication does not indicate concentrations of Flit MLO, Abate or malathion,
it provides innumerable examples of the biological concentration of DDT.
For instance, the eastern oyster concentrated DDT 70,000 times after being
exposed to 0.1 ppb for 40 days; the croaker, a salt-water fish, concentrated
1 ppb DDT 20,000 times in a Long Island salt marsh, plankton concentrated the
DDT over the water concentration 800 times; and fish in a Florida tidal marsh
concentrated DDT up to 200 fold. In Lake Michigan alewife were found to have
10 times the DDT of amphipods, and the amphipods had 30 times the level found
f 321
in the Lake mud. J Microscopic organisms also accumulate pesticides. After
7 days at 1 ppm DDT algae concentrated the compound 200-fold and, Daphnia con-
centrated DDT 100,000 fold. Those fish which ate the Daphnia concentrated the
T321
pesticide even further. J Investigators at Gulf Breeze, Florida observed that
69
-------
DDT accumulation in the cells of Papameaium multimioTonuoleatum was 264
times greater and in P. busaria was 964 times greater than in the medium on
which they were cultured. ^ The occurrence of bio-concentration is what
most often leads to the deleterious environmental effects observed when persis-
tent pesticides such as DDT are used.
When an effective pesticide is used to eliminate bothersome organisms,
the most obvious result is a decrease in the pest population. The success
against mosquitoes of the four compounds under consideration (DDT, malathion,
Abate, and Flit MLO)has been implied in our discussion of toxicity and is well
documented?92'93'9'95'9-' However, there may also be other effects manifested
immediately or at a later time. Insecticide usage may decrease the insect
problem, but other organisms can be killed instead of or in addition to the
target insects.
In order to curb the tick population on Bull's Island, South
[97]
Carolina, DDT was sprayed manually and aerially on test plots. The
island is separated from the mainland by salt marsh and tidal creeks. The
majority of the test plots were in forest regions, although part of one was
on the salt marsh. Ond day after the marsh plot was sprayed with 2 Ibs. of
DDT/acre, 81% of the formerly abundant fiddler crab population was found dead
and more were presumably dying buried in sediment. Two species of arboreal
frogs had been abundant in the forest area, but they started falling from the
trees within two hours after treatment. By the second and third days after
spraying, a considerable number of these frogs were found dead or undergoing
"DDT paralysis." The spraying was very effective in eliminating several
species of mosquitoes and in decreasing the number of spiders, wood roaches,
beetles, crickets, grasshoppers, ants, and harvestmen.
70
-------
In an unpublished study, Abate was applied to test plots of a Cape
Cod salt marsh with varying results. ^ When applied at a dose of 0.4
Ib/acre, excellent control of Culiooides melleus mosquito larvae was obtained,
although fiddler crabs were killed. When applied at a dose of 0.3 Ib./acre,
Abate was ineffective against the Culiooides melleus larvae, but fiddler
crabs were killed again.
Crustaceans are quite susceptible to the three pesticides under
consideration, and fiddler crabs, copepods and shrimp have been found to be
adversely affected by them. When DDT was sprayed on salt marsh plots in
New Jersey, a 75% kill of the copepod population was recorded on the first
day, and by the second day the copepod population was seemingly eradicated.
On the llth day after treatment, there was a 45% recovery; by the 12th day,
the recovery was 80%; and on the 18th day the copepod population exceeded that
of the control plot. As long as the insecticide is not continuously applied,
the copepod population is able to reinstate itself. The investigators who sprayed
DDT on a tidal salt marsh ditch in Florida concluded that the reproduction of
all resident species of fish continued and restored pretreatment population
f 981
levels in 4 months. In this same experiment, however, a population of
shrimp (Palaemonetes sp.) was drastically reduced, and the original population
was not resotred in 4 months.
1. Biological Concentration of Pesticides
The environmental effects of pesticides are not always evident
immediately after spraying. Deleterious effects are often not discernible
for a long period after initial contact with a toxic material. It is commonly
believed that biological magnification of pesticides and their residues occurs
in food webs. A food web is composed of the interlocking food chains of an
ecosystem, such as in a salt water marsh. In such cases, those organisms which
do manage to survive exposure to pesticides and their residues are instrumental
71
-------
transmitting lethal and sublethal amounts of such materials to consumers,
both herbivores and carnivores. A number of examples of biological concentration
of pesticide residues in food webs pertinent to this discussion have been found.
The situation at Clear Lake, California provides a good example.
Clear Lake fs a very popular tourist area which had a serious problem with gnats.
The problem was recognized as early as 1916, and by September, 1949, it was
finally decided that the lake should be sprayed with DDD. The formulation used
resulted in an application of 1 part DDD in 70 million parts of water. The
gnat larvae kill was reported to be 99%, but in 5 years, the gnat population
had re-established itself sufficiently to warrant another spraying. Therefore,
an application of 1 part DDD in 50 million parts of water was applied to Clear
Lake in 1954, and again, the larval kill was 99%. This time, the gnat population
re-established itself in 3 years. Another application of insecticide was made
in 1958 using the same concentration of DDD. However, the percent kill of gnats
was observed to be less than the percentages obtained from previous applications.
A few grebes were found dead soon after each application of DDD but
3 months after the 1957 application, approximately 75 grebes were reported
dead on the lake s shores. Analysis of fatty tissue samples showed the con-
centration of DDD to be 1,600 ppm. Contaminated food was suspected to be the cause
of death so local fish were collected and samples of their fatty tissue were
analyzed. The amount of DDD found in the fat ranged from 40 ppm in carp to 2,5000
ppm in brown bullhead. Because there were no large-scale fish die-offs and since
residue concentrations were higher in some species of fish(catfish and large-
mouth bass) than they were in the grebes, it was concluded that grebes exhibit a
weaker tolerance for DDD than certain species of fish. A grebe diet consists
mostly of fish plus a few insects. Although these birds are subject to periodic
die-offs, circumstantial evidence strongly suggests that the grebe losses were
72
-------
caused by chronic poisoning from DDD. It is believed that the DDD was
accumulated in the food web shown below, although its presence in planktonic
species of algae was not established.
^^^ detritus . ) insects _^_^
DDD on water ^ algae •^^") herbivorous fish > grebes
^*~"5* filter feeders ^ carnivorous fish
It has been shown by other researchers that marine phytoplankton
do contain DDT residues and that the uptake of these residues is rapidly and
essentially irreversible. -1 Very i0w concentrations (a few parts per billion)
of DDT in water reduced photosynthesis in laboratory cultures of four species of
coastal and oceanic phytoplankton representing four major classes of algae and in
r g£ "1
a natural phytoplankton community. Thus the presence of insecticide residues
in the first link of the food chain is possible.
A salt marsh ditch on Santa Rosa Island, Florida, was sprayed with DDT
F981
for experimental purposes. Eight of the 12 fish species present in the marsh
ditch were placed in enclosed holding, sites. The mortality of the confined fish
was 37.7% at one site and 91.3% at another site close to the mouth of the ditch.
Vegetation concentrated DDT residues to a maximum of 75 ppm 3 to 4 weeks after
treatment. Fish and vegetation accumulated up to 1,500 times the maximum amount
of DDT residues detectable in the water, while for snails and fiddler crabs the
accumulation values were 144 and 99, respectively.
Evidence indicating the biological concentration of DDT residues was
also obtained from an extensive salt marsh on Long Island. The marsh was
not treated with pesticides but had most likely accumulated residues from the
river which empties into it. The concentration of residues in organisms increased
with succeeding trophic levels; larger organisms and higher carnivores having
greater concentrations. The concentrations of DDT residues in raptorial birds were
10 to 100 times those in the fish on which they feed.
73
-------
Investigators at the University of Illinois designed a simulated
ecosystem with a terrestrial-aquatic interface and a seven-element food chain
which simulates the application of pesticides to crop plants and the eventual
contamination of the aquatic environment. They applied radiolabeled DDT
and terminated the experiments after 33 days at which time samples were examined
for DDT, DDE, ODD and polar compounds. The food chain pathways in the
simulated ecosystem were:
v. Algae ^ Snails
^*
Sorghum ^ Salt marsh caterpillers —> Diatoms ^ Plankton
Plankton -^ Mosquitoes ^ Mosquito Fish
It was demonstrated that mosquito fish concentrated and stored DDT in their
tissues at a level which was approximately 11,500 fold over the level of radio-
labeled DDT in the aqueous phase of the ecosystem.
Investigators at the Cranberry Experiment Station of Cape Cod,
Massachusetts, devised a model cranberry bog, treated it with radiolabeled
parathion (an organophosphate), simulated a frost protection flood 24 hours
after treatment with the pesticide, and exposed fish and mussels to the run-off
water. The concentration of parathion in the flood water was 0.12 ppm and in
the aquarium water it was diluted to 0.07 ppm. Only 20% of the fish (Fundulus
heteroelitus) survived the 24 hour exposure in the aquarium. The dead fish
concentrated the parathion to a level of 1.7 ppm, an amount 80 times greater than
that in the water at the same period. After 48 hours the level rose to 2.11 ppm,
but by 96 and 144 hours it dropped to 0.21 ppm. The mussels also accumulated a
substantial amount of parathion, 0.99 ppm.
Measuring the levels of pesticide residues in dead organisms is useful
for determining the rate of residue accumulation in the food web, but one may
not assume that the organisms' deaths were a direct result of high residue levels,
since such an assumption is invalidated by the fact that analyses of live fish
74
-------
have often indicated higher residue levels than those of dead fish from the same
(
ecological conditions. The duration of exposure, the treatment dose, the extent
of food contamination, the persistence of the insecticide and its breakdown
products, and possible synergism, must all be considered.
2. Effects in Cape Cod Marshes
When it first became apparent that the concentrations of DDT and
organophosphates in our study areas were very low, we noted in passing that these
concentrations appeared too low to cause toxicity. In the case of our specific
study areas, it has been a year and a half since either an organochlorine or organo-
phosphate insecticide has been applied for the purpose of controlling mosquitoes.
Flit MLO has been used for spraying this year and only 21 gallons of 2% malathion
solution were applied in all of 1970 (and that probably in the spring only).
Thus, if we are to gain information about the possible effects which might have
occured in the past as a result of the vectoricide program on Cape Cod, it is
necessary to determine the concentration of vectoricides which would have been
found in the marshes immediately following the appplication of malathion and
Abate in the past, and of Flit tfLO currently.
[23]
The data provided to -us by the Cape Cod Mosquito Control Program
reveals that the greatest quantity of malathion applied to the Bass Hole Marsh
was 83 gallons of the oil solution. In 1969, the peak use of Abate was experienced
in our two study areas; 60 1/2 gallons of Abate solution were applied to the
Bass Hole Marsh area and 38 1/2 gallons to the Herring River Marsh. The peak
reported use of Flit MLO was in 1970 when 18 3/4 gallons were applied to the
Bass Hole Marsh and 8 gallons to the Herring River Marsh.
The final concentration of malathion in the oil solution used was 0.17
Ibs. per gallon and the concentration of Abate solution as applied was 0.003 Ibs.
per gallon. Thus, the maximum amount of organophosphate insecticide applied to
either of the marshes in a single year was 14 Ibs. of malathion in 1968 and 0.2
Ibs. of Abate in 1969- However, these applications were made at several times and to
several areas within the marshes.
75
-------
The highest application rates of record for a particular vectoricide
to a specific treatment site our study reveals the application of 10 gallons
of oil solution equivalent to 1.7 pounts of pure malathion, 15 gallons of Abate
(0.045 pounds) and 4 gallons of Flit MLO. By making use of the United States
Geological Survey maps of the Dennis Quadrangle and Harwich Quadrangle and a
compensating polar planimeter we determined the approximate acreage of these areas
and calculated maximum application rates of 0.02 Ib./acre malathion, 0.0006 Ib/acre
Abate and 0.04 gallon/acre Flit MLO.
While malathion has not been found to be toxic at the level applied
the application of 0.02 Ibs. per acre does approach the level of 0.1 Ibs. per
acre of the more toxic and active Dursban, which has been found to have killed
f 951
fiddler crabs at this latter concentration. The same studies did indicate
however, that at the rate of 0.05 Ibs. of Dursban per acre, no mortality to
fiddler crabs or other organisms in intertidal sand plots was observed. Dursban
[32]
has been found to be five times as toxic as malathion to invertebrates.
It should be realized, however, that the hand applications of malathion
at the maximal 0.02 Ibs. per acre are to very limited areas of the marsh and
even if some mortality were by some chance to occur in one particular area,
immediate repopulation from adjacent areas would be expected. Also, the highest
concentrations of pesticide were used earJ-7 in the spring, prior to the appearance
of the sensitive larval stage of most important fish species except the flounder.
During the years when malathion was used in the greatest quantity in our
study areas (1968 in the Bass Hole Marsh, and 1967 in the Herring River Marsh),
the rate of application for the entire year was 0.013 Ibs. per acre for the Bass
Hole Marsh and 0.005 Ibs. per acre for the Herring River Marsh. The maximum
application of Abate over an entire season (1969) was 0.0002 Ibs. per acre for
the entire season in both the Herring River Marsh and Bass Hole Marsh areas.
At 0.25 Ibs. per acre, Abate is reported to cause no noticeable mortality of
ostracods and copepods.
76
-------
At these levels of application, it becomes impossible for us to be
able to predict any significant toxic results within the marsh ecosystem.
There indeed may be species sensitive to either of the organophosphates
or to Flit MLO, but it must remain our conclusion that the local application
of toxic pesticides to the two marshes which we have studied does not produce
the risk of significant toxic effect to important species. Also, the current
use of Flit MLO does not appear to have a lethal effect on any species in the
marsh and, since this material demonstrates little toxicity after dilution, it
is apparently of negligible concern to the generalized marsh ecocystem.
Numerous reports have appeared which indicate poisoning in estuarine
environments, but it becomes difficult to positively associate such
effects with vectoricide programs in the face of the numerous other potential
etiologic agents. Often,lethal effects in the marsh can as easily be assoicated
with other sources of pollution, the effect of oxygen starvation, or an
epizootic. However, some papers reveal concentrations of material (almost
always DDT) in animals within marsh ecosystems which approach concentrations known to
be toxic. While this work is not to be denied, and while such data cannot
be obtained from our study areas, a few comments concerning the possibility of
significant toxic effects arising from a vectoricideprogram should be made.
DDT has no effect on salt marsh microorganisms when applied at levels
as high as 1.75 Ibs. per acre but the concentration of such a persistent
material through the food chain can result in a lethal dose for organisms at
higher trophic levels in the food chain. However, in New England where DDT has
been removed from use as a vectoricide, and few other organochlorine materials
are used, the possibilities for build-up through the food chain have decreased
and, thus, outright lethality as a result of vectoricide programs have become
less critical. The immediate toxic effects of other pesticides would have been
more easily observed in the course of their use.
77
-------
Effects of poisoning other than by outright lethality must also
be considered. Those animals which lose coordination as a result of the
inhibition of acetylcholinesterase or, in the days of DDT, those animals
whose eggs become less likely to survive, are indeed being poisoned by
vectoricides while not being killed. The problem with documenting this
kind of poisoning is that the results ofttimes lag significantly beyond the
time of treatment. Here too, though, the demise of persistent materials has
greatly overcome the problems associated with poisoning. Those organophosphate
materiaJs which produce a sublethal effect in organisms now are either metabolized
in the organism and allow it to recover, or compromise the organism thus
removing it from the population. The removal of organisms can have the effect
of resulting in a food deficit for animals of higher trophic levels.
Starvation does produce a delayed effect although a close observation
or population count of what are normally considered to be less important
organisms could predict the eventual starvation of higher ones. It is possible
that in some of the vectoricide programs currently in operation, decrease in
the invertebrate population is, in turn, leading to malnutrition in higher life
forms. While this may seem an unusual result, such malnutrition has already
been observed in fresh water systems where the aquatic insects are most vulnerable
to the use of pesticides. In local fresh water marshes, for instance, a state
of protein deficiency has been observed in young wood ducks, presumably as a result
of a lack of the aquatic insect foodstuffs upon which they feed following hatching.
One area which is increasing as a problem is that involving synergistic
effects. The ability of several materials to produce a toxic situation
greater than the sum of each individual materials' cannot be effectively evaluated.
In many estuarine environments a vaiiety of pollutants enter the environment and
may have the opportunity to comprise already weakened organisms. It is possible in
such situations to trace the multiple effects which have led to lethality,
78
-------
With agents other than traditional pesticides, (such as the Flit
MLO, which is currently being used in the Cape Cod marshes) other questions
will perhaps be raised in the future. At the present time, however, little
in the way of detrimental effects on the biota of the salt marsh can be
attributed to the use of Flit MLO. In fresh water, water boatmen bugs and
certain beetle larvae and adults have been killed because they cannot get to
the air above the larvicide oil. In the salt water marshes, this would not
appear to be a problem as analogous species have not been identified. Also, larger
organisms such as the tadpole which does have to reach air, are not in any way
interfered with by the mosquito larvicide oil. This is not to say that
problems in the future may not develop insofar as toxicity but no evidence based
upon our study of either the literature or the Cape Cod salt water marshes
indicates any such problem.
D. Impact of Vectoricides on Man
In discussing, finally, the impact of the vectoricide program in our
Cape Cod study areas on man it is important to realize that the most dramatic
effect of this program has been a beneficial one. There is no doubt that the
vectoricide program has, in fact, yielded a high measure of control of the
mosquito population of The Cape. A major benefit of mosquito control in the
Cape Cod area, in addition to preventing the spread of disease, relates to
improving the enormous recreational value of the area. At least part of
people's desire to utilize the Cape Cod region is founded on the peace and
uniqueness of the habitat as contrasted to the urban environment. It may be
argued that in the absence of mosquitoes this is a false environment, but it
truly cannot be argued that effective mosquito control permits a much larger
number of people to observe and enjoy this environment more comfortably.
-------
When dealing with the adverse effect of mosquito contol programs
on man, however, esthetic considerations become difficult to resolve with the
general question of human safety. Innumerable articles have appeared on this
subject in both the lay and scientific press all introducing measure of
philosophy in establishing the relative value of esthetic,
toxicological and quality-of-life arguments. The economists have delved
into elaborate systems for establishing the cost-effectiveness of both the
use and control of pesticides and the commercial value of the preservation
of distinct environments such as the salt water marsh. Writers have balanced
the concept of elitism (in that it is the few who actually benefit from the
1112]
utilization of wilderness areas) versus progress. Scientists have
written logical arguments for sanity in the evaluation of environmental problems.
While it is impossible to resolve the multi-faceted aspects of these philosophical
discussions in general, certain points concerning esthetics can be raised in regard
to the salt water marsh environment as found on Cape Cod.
The major fact arising from the previous section of this report is that
little or no toxic effects arise from the use of vectoricides for mosquito
control as currently practiced in our two study areas on Cape Cod. Mosquitoes
are killed, and when toxic chemicals were used previously, it is probable that
death resulted to a small percentage of certain sensitive invertebrate species.
However, because of the short half-life of these particular insecticides,
malathion and Abate, the effect of the poisoning of such invertebrates was not
passed down the food chain (we are not concerning ourselves here with any
hazards which may exist for the applicators).
It is a strange quirk of man that esthetics apparently relates to birds
a great deal more than it does to arthropods. Man can make much greater arguments
for preventing diminished numbers of bald eagles and ospreys than he can for the
decimation of lowly slime-entombed invertebrates. If our calculations are correct
80
-------
and the birds of the Cape Cod marshes are not affected by the mosquito control
program and few mammals and other land invertebrates will be affected we can resolve
the esthetic argument down to a question of the extent to which periodic,
localized decreases in invertebrates will affect the "esthetics of the salt
marshes" as related to man.
Before drawing a final conclusion, it is important to remember
that the basis for the mosquito control program currently being utilized in the
F231
Cape Cod salt marshes is ditch digging.1 J An aerial map of our study are
reveals extensive major drainage ditches present in these marshes (36.7 surface
miles in Chase Garden Creek section of the Bass Hole Marsh) which are kept in
continual repair, both by brush cutting in the summer and reditching in the
[23]
winter. This method of controlling mosquitoes definitely does affect the
marsh ecosystem. The specific changes in fauna which accompany this
increased drainage and their importance insofar as food chains have not been
determined. However, in the Bass Hole Marsh the southern regions abutting
Whites Brook contain extensive pannes with their associated distinctive vegetation.
In terms of man, then, the negative effect of ditching would appear to be solely
one of esthetic value insofar as the ditches leave a marsh "unnatural."
However, ditching has been carried on throughout the northeast coast marshes
for such an extended period of time that probably few people can now relate to
an unditched marsh.
If esthetics are discounted and toxicological hazards eliminated it
is then economic considerations which are left. It was repeatedly indicated
at thestart of this section that the salt marsh is a major factor in the
feeding of large fishes and shellfish which are of economic value. Proceeding
in phylogenetic order, one can evaluate stepwise the economic impact of the
mosquito control program in these marshes. In some New England marshes, salt
hay and seaweed are a cash crop , but have little economic value on the
Cape. However, in addition, the marshes under study are not heavily involved
81
-------
in the shellfish: harvest which is significant on Cape Cod. No mussels are
harvested in either of our two study areas as in the nearby North River, and
the Herring River Marsh especially does not encourage the organized harvest
of soft shell clams. The Bass Hole Marsh does feed into Barnstable Harbor
in which a reasonable amount of clara-digging is performed. However, the number
of soft shell clams harvested at the mouth of the Bass Hole Marsh must be considered
to be below the 1300 bushels harvested from the North River in 1965 and thus
below a value of $15,000 per year. This figure does not include the number
of shellfish removed from Barnstable Harbor by family diggers, licensed to use
the clam flats.
There is an organized culture clam venture located near the mouth of
the Bass Hole Marsh and water is drawn from the marsh to nurture the spawn and
young clams in these commercial pools. There have been occasional
"clam kills" at these pools, but there has not been any evidence linking them
to the organized vectoricide program conducted in the Bass Hole Marsh. These
clam kills may be the result of other insect control programs such as tree insect
control, or they may also be the result of natural failure of seed clams (bio-
chemical analysis of the dead clams could not be performed). The value of this
organized commercial activity in jobs and dollar value has not been determined
since it is a private and closely held organization.
The value of oysters and quahogs harvested as compared to the soft
shell clam industry is negligible. Although lobster are occasionally found at
the mouth of the Bass Hole Marsh, the area does not support an organized
lobster fishery. Similarly, the value of fish caught directly in the marshes
or in the mouths of thse marshes is negligible. There is little direct economic
benefit as the result of sport fishery fees in these particular areas. However,
the marsh does contribute to the nutrients consumed by the larger fishes which
make up the North Atlantic commercial and game fishery. The extent to which the
82
-------
vectoricide program could decrease fish yields in the North Atlantic however,
is probably small.
As has been indicated before, the menhaden consumes vegetation
and, as such, can be considered a primary consumer of insecticides. Althougl
the menhaden catch goes almost entirely into fish protein materials and into
animal feeds and petfoods, it is important as the largest fish catch in the
United States. Because no concentration step of lipophilic materials (such as
DDT) occurs prior to consumption by the menhaden, one would expect that this fish
would not greatly experience the effect of the vectoricide programs. By observa-
tion, there would also appear to be sufficient mummichogs, the other primary
consuming commercial marsh fish, to serve their function as bait in the most heavily
treated portions of the marsh.
With the carnivorous fish such as the striped bass and mackerel, a
different situation exists. These fish consume smaller fish or invertebrates'
that have in turn consumed other animals or plants. As indicated in our section
on the concentration of insecticides in food chains, these animals can be exposed
to high levels of persistent pesticides and produce even higher levels within
their body tissues. Besides making such exposed fish less desirable in commerce,
this bioconcentration has the effect of producing toxic symptoms in such fish and,
in fact, toxic levels of DDT have in the past been found in many fish species.
Even if such outright lethal toxic levels are not reached, levels which can
be detrimental to behavior may arise and, as such lead to decreased survival
opportunity.
In terms of our study areas on Cape Cod, however, it is reported
that no DDT has been used in either the Bass Hole Marsh or Herring River Marsh
in the last 10 years. Thus, little contribution to the DDT content of fish or their
food can have resulted from the vectoricide program. Other sources of DDT,
especially vaporization and atmospheric transport appear to be more significant
83
-------
in their contribution to the marine environment. The malation and
Abate which have more recently been used are not persistent in water or organisms.
The insulating value of the food chain between the primary consumers and the
carnivorous larger fish, which exist only in the mouth of the marsh, probably
protect these species from the effect of either malathion or Abate.
One might make an argument for an overall decrease in the ability of
the salt water marsh to trap nutrients into higher life forms if certain of the
invertebrate classes are periodically decreased by the application of pesticides.
While a severe depletion of food organisms at any point in the life cycle would,
in fact, decrease the small fish on which the carnivorous and commercially
important fish are dependent, such would appear not to be the case in Cape Cod
marshes. The exceptionally low level of vectoricide material used, its
restriction to the borders of the salt water marsh and the proven ability of
the marsh life to rebound rapidly from this exposure to organophosphate
materials, would indicate a lack of such involvement. Further, even if some
small decrement in trapped nutrients in invertebrate animals were noted in the
marsh, it is likely that this decrease in food supply by itself would have
little effect on the commercial fishing in the face of the multiple other factors
tending to decrease the fish population. Those factors include over-fishing,
generalized water pollution, and commercial development of seaside areas, thus
decreasing nutrient supply in other ways. Whereas the direct toxic effect of
a persistent vectoricide on a species would have environmental impact, the effect
of a decrease in the food supply at the current time would probably only represent
a weak link in a chain with considerably weaker links.
84
-------
The effect of Flit MLO is somewhat difficult to assess. The inability
to determine true toxicity is both a hindrance but also an indication of the
unique nature of this material. It is highly refined mineral oil, and its
effect is to temporarily form a barrier to prevent organisms from obtaining
atmospheric oxygen. Such a barr,.tr appears to be quite effective in causing
the death of mosquito larvae, but the number of other aquatic species that use
atmospheric oxygen rather than dissolved oxygen is quite limited. For instance,
large schools of mummichog in the upper channels of the Bass Hole Marsh have
been observed living without distress under layers of oil.
If such oil were to remain for a considerable amount of time in the
upper reaches of the marsh, oxygen depletion would occur. However, the oil film
has a limited lifetime and we cannot hypothesize any significant impact upon
the marsh fauna caused by oxygen deprivation. The fact that the Flit MLO is
sprayed by hand specifically into stagnant aquatic areas would also tend to
negate the importance of its lipophilic character in interfering with land-basr d
life. The Flit MLO thus may alter the appearance of the upper marsh channels
for a couple of days following use, but would appear to be innocuous to man as
currently used in our Cape Cod study areas.
While it is quite obvious that the extensi \e use of persistent
pesticides can have a disruptive effect on the ecology of productive salt marsh
areas, as has been observed experimentally and has been hypothesized on the basis
of decreased production accompanying the use of DDT, it would appear that except
for decreasing the population of mosquitoes and, thus, perhaps compromising those
species directly dependent upon the mosquito as a foodstuff, the impact of
vectoricide pollution on the water environment of our Cape Cod study areas is
negligible. Also, in summary, it w• uld appear that the impact of vectoricides on
man, based on the mosquito cent' rogram as practiced on Cape Cod, can only
be concluded to be, on balance, - jntageous. The mosquito population has been
85
-------
reduced, thus, all but eliminating a disease threat and improving the
recreational aspects of the land area. At the same time, there has not been an
evidenced decrement to either the esthetic or economic value of the estuarine
environment.
86
-------
BIBLIOGRAPHY
1 Redfield, A.C. Estuaries, G. Lauff (Ed.), AAAS, Washington, D.C. (1967).
2 Cape Cod 1980, Sector of the Massachusetts State Plan, Blair Associates,
Inc., College Hill Press, Providence, Rhode Island (1963).
3 Ayers, J.C. Limnol. Oceanography _4,448-462 (1959).
4 Swain, R.B. The Insect Guide, Doubleday and Company, Garden City,
New York (1952).
5 Lee, A.B. The Microtomists' Vade-Mecuro, P. Blakiston's Son and Co.,
Philadelphia (1921)
6 Clegg, J. The Observer's Book of Pond Life, Frederick Warne and Co.,
New York (1956).
7 Teal, J. and Teal, M. Life and Death of the Salt Marsh, Ballantine
Books, Inc., New York (1969).
8 Odum, E.P. and Odum, H.T. Fundamentals of Ecology, W.B. Saunders Company,
Philadelphia, 344 and 365 (1959).
9 Niering, W.A. The Life of The Marsh, McGraw-Hill and The World Book
Encyclopedia, New York (1966).
10 Odum, W.E. Trans. Amer. Fish. Soc. 100, 836-346 (1970).
11 Riley, G.A. Estuaries, G. Lauff (Ed.), AAAS, Washinton, D.C. (1967).
12 Seagle, E. Estuaries, G. Lauff (Ed.), AAAS, Washington, D.C. (1967).
13 Roberts, M.F. Tidal Marshes of Connecticut, Connecticut Aboretum,
New London, Connecticut (1971).
14 Petry, L.C. and M.G. Norman. A Beachcomber's Botany, The Chatham
Conservation Foundation, Inc., Chatham, Mass. (1968).
15 Hinds, E.R. and W. A. Hathaway. Wildflowers of Cape Cod, The Chatham
Press, Inc., Chatham, Mass. (1968).
16 Lackney, J.B. Estuaries, G. Lauff (Ed.), AAAS, Washington, D.C.
291-302 (1967).
17 Ketchum, B.H. Ecology 35, 191-200 (1954).
18 Sanders, H.L., E.M. Goudsmit, E.L. Mills and G.E. Hampson, Limnol &
Oceanogr. 7^, 63-79 (1962).
87
-------
19 Teal, J.M. Ecology _43_, 615-624.
20 Miner, R.W. Field Book of Seashore Life, Van Rees Press, New York (1950).
21 Borror, D.J. and D.M. DeLong, An Introduction to the Study of Insects,
Holt Rinehart and Winston, Inc. (1964).
22 Murray, J.W. Micropaleontology _14, 425-455 (1968).
23 Doane, 0. Personal communication (1971)
24 Coates, P.G. Personal communication.
25 Hill, N.P. The Birds of Cape Cod, Massachusetts, Morrow, San Diego (1965).
26 Bailey, W. Birds of the Cape Cod National Seashore and Adjacent Areas,
Eastern Natl. Park and Monument Association (1968).
27 Hellebust, J.A. Estuaries, G. Lauff (Ed.), AAAS, Washington, D.C. (1967).
28 Shuster, Jr., C.N. The Nature Of A Tidal Marsh, The New York State
Conservationist, August-September, 1-8 (1966).
29 Buchsbaum, R. and M. Buchsbaum. Basic Ecology, Boxwood Press, Pittsburgh,
Pa, 77 (1957).
30 American Cyanamid Co., Technical Information on Abate, Mosquito Larvicide
and Insecticide.
31 Lowe, J.I., P.D. Wilson and R.D. Davison, In Progress. Report of the
Bureau of Commercial Fisheries Center for Estuarine and Menhaden Research,
Pesticide Field Station, Gulf Breeze, Fla., Circular 335 (1969).
32 Pimentel, D. Ecological Effects of Pesticides on Non-Target Species,
U.S. Govt. Printing Office, Washinton, D.C., 1-20 (1971).
33 Tucker, R.N. and D.G. Crabtree. Handbook of Toxicity of Pesticides to
Wildlife. U.S. Fish Wildl. Serv., Bur. Sport Fish Wildl., Resource Publ.
No. 84 (1970).
34 McCarty et al. J. Amer. Vet. Med. Assoc. 152, 279 (1968).
35 Gains et al., Archs. Envir. Hlth 14, 283 (1967).
36 Turner, N. DDT in Fish: Second Report Circular of the Connecticut
Agricultural Experiment Station, New Haven, #232 (1970) .
37 Hansen, D.J. In Progress Report of the Bureau of Commercial Fisheries
Center for Estuarine and Menhaden Research, Pesticide Field Station,
Gulf Breeze, Fla., Circular 335 (1969).
88
-------
38 Macek, K.J. and W.A. McAllister. Trans. Araer. Fish. Soc. 99, 20-27 (1970).
39 Henderson, C., Q. H. Pickering and C.M. Tarzwell. Trans. Amer. Fish. Soc.
88, 23-32 (1959).
40 McKee, J.E. and H. W. Wolf (Editors), Water Quality Criteria Second Edition,
Pub. No. 3-A (1963)
41 Naishtein, S. Ya., E. E. Klebanova, L.A. Tomashevskaya, and A.I. Lur'e,
Gigiena i Sanit. _33_(l-3), 47-52 (1968).
42 Gains, T.B. Toxicol. Appl. Pharmacol. 14 (3), 515-555 (1969).
46 Risebrough, R.W., D.B. Peakall, S.G. Herman, M.N. Kirven. Nature 220,
1098-1102 (1968).
47 Tarjan, R and T. Kemeny. Food Cosmet. Toxicol. 7_, 215-221 (1969).
48 Heinrichs, W.L., R.J. Gellert, J.L. Bakke and N.L. Lawrence. Science 173,
642-643 (1971)
49 Heath, R.G., S.W. Spann, and J.F. Kreitzer. Nature _224^ 47-48 (1969).
50 Mount, D.I. and C.E. Stephan, Trans. Am. Fish Soc. g6, 185-193 (1967).
51 Pickering, Q.H., C. Henderson and A.E. Lemke. Trans. Amer. Fish.Soc.
jtt, 175-184 (1962).
52 Micks, D.W., G.V. Chambers, J. Jennings and K. Barnes. J. Econ. Entomology
61, 647-650 (1968).
53 Marketing Technical Services, Humble Oil & Refining Co., Technigram.
D238-E, September 17 (1969) pp. 1-4.
54 Marketing Technical Services, Humble Oil & Refining Co., Technigram.
D238-E, September 17 (1969) pp 1-2.
55 Marketing Technical Services, Humble Oil & Refining Co., Technigram,
D238-B, September 19 (1969) pp 1-2.
56 Davis, T.R.A., A.W. Burg, J.L. Neumeyer, D.M. Butters, B.D. Wadler.
Water Quality Criteria Data Book V. I Organic Chemical Pollution of
Fresh Water. U.S. Government Printing Office, Washington, D.C. (1970).
57 Falk, H.L., S.J. Thompson and P. Kotin. Arch. Environ. Health 10, 847-858,
(1965).
58 Fitzhugh, O.G. and A.A. Nelson. J. Pharmacol. Exp. Therap. 89, 18-30 (1947)
59 Tarjan, R. and T. Kemeny. Food Cosmet. Toxicol. _7_(3), 215-221; 266-267,
(1969)
^O Report of the Secretary's commission on pesticides and their relationship
to environmental health, Washington, D.C. U.S. Department of Health,
Education and Welfare (1969).
89
-------
61 Epstein, S.S. and H. Shafner. Nature, 219, 385 (1968).
62 Marliac, J.P. Federation Proc. 23, 105 (1965).
63 Shubik, P. and J.L. Hartwell. U.S. Government Printing Office,
PHS No. 149 (1957).
64 Anonymous. Food Cosmet. Toxicol. ]_, 79-83 (1969).
65 Khera, K.S. and L.L. Whitta. Can. Med. Assoc. J. 100, 167-172 (1969).
66 Shubik, P. U.S. Government Printing Office, PHS No. 149 (1957).
67 Woodwell, G.M., C.F. Wurster and P.A. Isaacson. Science 156, 821-824,
(1967).
68 Hart, L.G. and J.R. Fouts. Naunyn-Schmiedebergs Arch. exp. Path. u.
Pharmak. 249, 486-500 (1965).
69 Peakall, D.B. Nature _216^ 505-506 (1967).
70 Peakall, D.B. Scientific American ^22_, 72 (1970).
71 Hickey, J.J. andD.W. Anderson. Science l^, 271-273 (1968).
73 Ratcliffe, D.A. Nature _215_, 208-210 (1967).
74 Enderson, J.H., D.D. Berger. Presticides, BioScience _20_, 355-356 (1970).
75 Wurster, C.F., Jr. Science 159, 979-981 (1968).
76 Gordon, H.T. and J.H. Welsh. J. Cell. Comp. Physiol. 31, 395 (1948).
77 Welch, R.N., W. Levin and A.H. Conney. Chemical Fallout - Current
Research on Persistent Pesticides. Thomas, Springfield, Illinois,
390-407 (1968).
78 Janicki, R.H. and W.B. Kinter. Science r73_, 1146-1147 (1971).
79 Mayhew, J. Proc. Iowa Acad. Sci., 62, 599-606 (1955).
80 Aubin, A.E. and P.H. Johansen. Canad. J. Zoology, 47, 163-166 (1969).
81 Anderson, J.M., H.B. Prins and J. Fish. Res. Bd. Can, 27, 331-334 (1970),
82 Weiss, C.M. Sewage Ind. Wastes, 3^(5), 580-593 (1959).
83 Wirth, W., G. Hecht and C. Gloxhuber. Toxikologie-Fibel, 353-355 (1967).
84 Keith, J.O. Letter from Fish and Wildlife Service, Davis, California
to American Cyanamid Company, February 15, 1966.
90
-------
85 Butler, P.A., A.J. Wilson, Jr. and A.J. Rick. Proc. Nat. Shellfisheries
Assoc., 51, 23-32 (1960).
86 Wurster, C.F., Jr. Science, 18_, 1474-1475 (1968).
87 Murphy, S.D. Residue Rev. No. 25, 201-221 (1969).
88 Huang, J.-C. Journal of the Water Pollution Control Federation, 43,
1739-1748 (1971). ~
89 Lichtenstein, E.P., K.R. Schulz, R.F. Skrentny and P.A. Stitt.
J. Econ. Entemology, _5_8, 742-749 (1965).
90 Diamond, J.B., G.Y. Belyea, R.E. Kandunce, A.S. Getchell and J.A. Blease.
Canad. Entomol. 102, 1122-1130 (1970).
91 Croker, R.A. and A.J. Wilson. Trans. Am. Fish. Soc. £4, 152-159 (1965).
92 Clancey, B.M., C.S. Lofgren, J. Salmels and A.N. Davis. Mosquito
News 25_, 135-137 (1965) .
93 Micks, D.W. and J.A. Berlin. J. Econ. Entology, 63, 1946-1957 (1970).
94 Micks, D.W. J. Econ. Entomology, 63. 1118-1121 (1970).
95 Wall, W.J., V.M. Marganian, R. Benton and R.A. Coler, "The Effect of
Selected Pesticides on Intertidal Biota", in press.
96 Ruber, E., F. Ferrigno. Some Effects of DDT, Baytex and Endrin on
Salt Marsh Productivities, Copepods and Aedes Mosquito Larvae.
Proceedings of the 51st Meeting of the New Jersey Mosquito Extermination
Association, Atlantic City, N.J., 85-92 (1964).
97 Goodrun, P., W.P. Baldwin and J.W. Aldrich. J. Wildlife Management, 13,
1-10 (1949).
98 Croker, R.A. and A.J. Wilson. Trans. Amer. Fish. Soc. 94, 152-159 (1965)
99 Linn, J.D., R.L. Stanley. Calif. Fish and Game, 55, 164-178 (1969).
100 Hunt, E.G. and A.I. Bischoff. Calif. Fish and Game, 46, 91-106 (1960).
101 Cox, J.L. Science, 170, 71-73 (1970).
102 Metcalf, R.L., G.K. Sangha and I.P. Kapoor. Environmental Science &
Technology, _5, 709-713 (1971).
103 Miller, C.W., B.M. Zuckermand and A.J. Charig. Trans. Amer. Fish. Soc.
95, 345-349 (1966).
104 Colton, J.B., Jr. and R.R. Marak. Guide for Identifying the Common
Planktonic Fish Eggs and Larvae of Continental Shelf Waters, Cape Sable
to Block Island, Bureau of Commercial Fisheries, Woods Hole, Mass.
No. 69-9, 1-43 (1969).
91
-------
105 Butler, P.A. Sport Fishery Abstracts, lj> 179 (1971).
106 Ruber, E, md D.M. Jobbins. Proceedings on the Forty-Eighth Annual
Meeting ff The N.J. Mosquito Extermination Association, 159-163 (1961).
107 Hatfield, C.T. Canadian Fish Culturist, 40_, 61-72 (1969).
108 Grice, D. Personal communication (1969).
109 Zavon, M.R. BioScience, 19_, 892-895 (1969).
110 Humble Oil and Refining Company, Unpublished Observations, Evaluation
of Flit MLO for Control of Early Spring Aedes spp. in Woodland Pools,
Delaware (1968).
Ill Harrison, G. Saturday Review, November 6 (1971), 77-86.
112 Stokinger, H.E. Science, 174. 662-666 (1971).
113 Hayes, W.J., Jr. Bull. Wld. Hlth. Org., 44_, 277-288 (1971).
114 Rankin, J.S., Jr. The Connecticut Arboretum Bulletin No. 12, 8-12
(1961).
115 Jerome, W.C., Jr., A. P. Chesmore and C.O. Anderson, Jr. A Study
of the Marine Resources of the Parker River-Plum Island Sound Estuary,
Division of Marine Fisheries, Dept. of Natural Resources, Mass., 1-79 (1968),
116 Fiske, J.D., C.E. Watson and P.G. Coates. A Study of the Marine Resources
of the North River, Division of Marine Fisheries, Dept. of Natural
Resources, Mass., 1-53 (1966).
117 Committee on Oceanography, Chlorinated Hyrocarbons in the Marine
Environment, National Academy of Sciences- Washington (1971).
92
-------
VII. _DEGRADATION OF PESTICIDES
AND METABOLITES IN THE VIATER ENVIRONMENT
In varying degrees, pesticides may be contaminating and accumu-
lating in man's food supplies as well as the soil, water, and air of his
environment. In this study, we have surveyed the literature pertaining to
the degradation and metabolism of two chlorinated hydrocarbon pesticides—
DDT and dieldrin—and two organophosphate insecticides—malathion and Abate—
under a variety of environmental conditions. The choice of pesticides
studied in this section was based on those chemicals which have at some time
been used for vector control in the area of our study.
A. INTRODUCTION
Studies of pesticide metabolism are necessary for several reasons.
From a practical viewpoint, information on the chemical behavior and reac-
tions of insecticides in biological systems is essential for the rational
assessment of hazards arising from the use of these compounds for vector
control. Clearly, the identification and establishment of the toxicological
properties of the metabolic products produced in plants, animals or by
environmental factors are mandatory before residual hazards may be assessed.
(Such toxicity effects will be discussed in another section of this report.)
In addition to assessing the toxicological effects, data on the metabolic
breakdown of pesticides, particularly in animals and microorganisms are
basic to our understanding of the mode of action of such chemicals. Such
information is of paramount importance for the elucidation of the intoxication
and detoxification processes that occur in animals, plants, and microorganisms.
As shown in Figure VII-1, when a pesticide is applied to plants,
animals, soils, water or air, there are many factors that may effect chemical
changes. The rates of such alterations will depend on the nature of the
93
-------
Pesticide
I
Soil
Animals
Plants
Microorganisms
Climate
Metabolic Factors
vo
*-
Molecular Changes
Oxidation Hydrolysis Reduction Conjugation
Physical Factors
Climatic
Parameters
light
rain
wind
temperature
Growth
T
I
Dilution New Tissue Storage
I I I
Penetration Transport Systemic
I
Oil
Solubility
T
T
Water
Solubility
Protein Bound Molecular Dimension Cell Membrane
FIGURE VI1-1
FACTORS AFFECTING THE FATE OF A PESTICIDE
-------
pesticide and the particular environmental conditions to which it is sub-
jected. Various metabolic and physical factors will influence the fate or
rate of degradation of the parent pesticide. The metabolic factors as
illustrated in Figure vil-l will affect the fate of the pesticide and will
involve either molecular alteration or migration phenomena. Molecular
changes may be precipitated by chemical or enzymatic reactions such as
oxidation, hydrolysis, etc. Migration in plants or animals may be con-
sidered to occur either through simple penetration or via more involved
systematic transport mechanisms. Physical factors affecting the fate and
persistence of pesticides are also shown in Figure VII-1.
In the soil, several factors have been reported to affect the
behavior of pesticides. These factors include adsorption and desorption,
volatilization from soil surfaces, movement in soils, uptake by plants and
microorganisms, photochemical decomposition, chemical decomposition,
(catalytic and hydrolytic) and microbial decomposition. All these factors
contribute singly or in sequence in the processes of residue accumulation
and/or pesticide degradation in the soil. These factors, particularly the
last two, can equally influence the fate of the pesticide in water systems.
Photochemical decomposition on surfaces can be effected by the
influence of sunlight although it has only a practical energy range of
290 to 450 my. The mode of chemical decomposition can also be catalytic,
(due to presence of nitrogenous constituents, carbonates, sulfates, as
well as iron, manganese, cobalt, and aluminum salts) or hydrolytic (favored
by the high or low pH of soils, i.e., pH 3 - pH 10). Microbial decomposition
or biodegradation is brought about by the action of microorganisms like
F2 3 41
bacteria, streptomyces, fungi, and algae.1 ' ' The process generally
involves the following biochemical reactions—dealkylation, dehalogenation,
hydrolysis, oxidation, reduction, hydroxylation, ring cleavage and conjugation.
95
-------
The three types of decomposition discussed (metabolic, physical
and photochemical) are believed to be the major pathways for conversion
of pesticides into some other forms that can continue to persist or be
further adsorbed and metabolized in the natural environment. These
factors were taken into consideration in searching for and in sorting out
currently available data. Likewise, whenever applicable, the extent of
residue accumulation in soils and in natural waters was reviewed.
B. DECOMPOSITION MECHANISMS
1. Decomposition and Degradation of DDT
Photochemical degradation of DDT (I) by sunlight and heat or UV
irradiation has been reported. ''^ Both Broker1 J and Fleck1 claim
that in the presence of air, 4,4'-dichlorobenzophenone (DBF) (II) is formed,
but when air is absent 2,3-dichloro - l,l,4,4-tetrakis-(p-chlorophenyl)
2-butene (III) is formed.
Cl
CC13
V-//
I
H
(I)
(III)
96
-------
The dechlorination of DDT in isopropanol by exposure to cobalt
rgi
60 yrays was studied by Sherman. J He found that at low and high dose rates
dichlorodiphenylethane (ODD) is produced.
In the presence of small amounts of iron and aluminum salts, Fleck
and Haller ' report that DDT is converted to dichlorodiphenylethylene
(DDE) (V) . The dehydrohalogenation of DDT to DDE on homoionic clays was
also reported by Lopez-Gonzales, et al. ' ' DDE and ODD were also found
in heavy clay soil in water sheds treated with DDT. The active clay
surface probably catalyzed the chemical decomposition. DDT is also converted
to DDE by ammonia and other simple amines. The conversion of DDT to DDE
was greater in moist than in dry soils and was also increased by high
alkalinity.
The biodegradation of DDT by soil and water microorganisms under
aerobic or anaerobic conditions can produce DDE (V)t16~19] or DDD
respectively. The metabolic route is a function of the specific microorganism
ims ai
[32]
and the presence or absence of air. While several microorganisms are
capable of metabolizing DDT, a number of others cannot degrade DDT.
Several authors also reported on other probable microbial meta-
F331
bolites of DDT. Anderson found five unidentified metabolites that were
not identical with DDD, DDE, bis-(p-chlorophenyl)acetic acid DDA (VI),
DBF (II), dicofol (VII), and l,l-bis(p-chlorophenyl)ethane (VIII). The
extensive studies of Focht and Alexander ' showed that a Eydrogenomonas
cleaved one of the rings of p,p'-dichlorodiphenylmethane (IX), a known DDT
metabolite , and also that of diphenyl methane. The metabolites obtained
were p-chlorophenyl acetate and phenylacetic acid respectively.
Wedemeyer^ ^ reported that Aerobaeter aerogen&s metabolized DDT
by two different routes. By sequential analysis, he showed that one route
takes the metabolic pathway DDT -> DDD -»• DDMU (X) -*• DDMS (XI) •*• DDNU (XII) ->
97
-------
r o s "I
DDA (VI) ->• DBF (II). The further metabolism of DDAL J follows the sequence
DDA -> DPM (IX) -> DBH (VIII) -»• DBF (II). The second route involves direct
conversion of DDT to DDE (VI), Patil, et. alJ28^ claimed that of the twenty
microbial cultures they studied, 10 isolates degraded DDT to a dicofol-like
compound and 14 isolated degraded DDT to DDA.
Dimond'17^ conducted his study in the associated soils of Maine
forests from the first year of DDT application and for nine years thereafter.
He found that the "total residue" included psp'-DDT (main bulk of the residue),
o,p'-DDT (14 to 20% of the total residue through the 9 years),* and DDE. The
residue analysis reveals very little breakdown of DDT through the ten year
interval, and the residues were confined to the upper organic soil horizons.
r 38i
Similar results were obtained by Lichtenstein with DDT treated agri-
cultural loam soils. The amount of p,p'-DDT plus o.p'DDT recovered 15
years after soil treatment was 10-6% of the combined dosage of 10 Ib. per
acre. Soils that had been treated with DDT at higher dosages showed relatively
higher residue levels. DDE was the major metabolite found, but dicofol (VII)
was also detected. Although the insecticides had been applied and washed
into the soil to a depth of 5 inches, the 6-9 inch soil layer, 10 years later
contained about 30% of the total DDT residues.
risi
The studies of Swoboda, et. al., on heavy clay soils on three
Blackland Prairie water sheds in Texas showed that less than 16% of the
DDT (total of p.p-DDT, DDE and ODD) applied over a 10-year period was recovered
in the top 5 feet of the soil. Between 60 and 75% of the recovered DDT was
found in the top 12 inches of soil.
*.
Note: Technical DDT consists of approximately 84% of p,p'-DDT
and 15% o,p'-DDT.
98
-------
F39]
Deubert and Zuckerman reported on DDT residues in two cranberry
bog soils in Massachusetts. They found that residue accumulation appears
to be a function of the irrigation system used. Other workers have studied
the problem of DDT accumulation in soils and the general consensus is that
DDT tends to persist in contaminated areas to a large or small extent
depending on the particular environment.
Studies have also been reported on the fate of DDT in the lentic
environment, in rivers, * lakes, ~ sea water, ' in marine
organisms along costal California, and forest streams. The presence
of residual DDT and the metabolites DDE, DDD and DDNS was reported.
Metcalf, et al., ' ^ and Harrison, et al., reported on
the behavior of radio-labeled DDT in a model ecosystem to trace the various
pathways of translocation and metabolism. The major metabolites noted in
the water, snails, mosquitoes, and fish in the ecosystem were DDE and DDD.
Residual and accumulated DDT was also found in all. Eberhardt has
recently developed a mathematical model for the rate of loss of DDT in
water.
The five principal routes of DDT metabolism, reductive dechlorin-
ation to DDD, dehydrochlorination to DDE, and oxidation to Kelthane,
DBF, or DDA are shown in Figure VII-2 together with the other metabolic routes
that lead to the formation of compounds reported to be products of microbial
degradation in soil and water environment.
[64A]
In a recent article, Woodwell, et al., discussed the fate
and persistence of DDT and the implications to life from the buildup of
DDT in the global environment. They concluded that the concentrations in
the atmosphere and the mixed layer of the ocean logged by only a few years
behind the amount of DDT used annually throughout the world.
99
-------
FIGURE VII-2
ROUTES OP DDT DEGRADATION AND METABOLISM
DBF
0
a/~~Vc-/~~^
4
(II)
Kelthane or dicofol
Photochemical
oxidation
Cl
Reductive
dechlorination
dehydrochlorination
Oxidation
CH2
n
-C-
i
H
DDMS
Cl
(XI)
OH
Cl
1 DBH
A (XIII)
H
Cl
r\-cj \
C1 DPM
H
COOH
H
DBA
(VI)
ci
CH3
DDNS
(VIII)
CH2
CIV 7-C-
(XII)
DDNU
100
-------
2. The Metabolism and Degradation of Dieldrin
The metabolites and degradation products of dieldrin are shown in
Figure VII-3. Although dieldrin is remarkably stable to alkali, it is sus-
ceptible to decomposition under irradiation in the ultra-violet region of
o
the spectrum. Photodieldrin, obtained by irradiating dieldrin (2537 A) in
concentrated solution or the solid state is identical with that present in
dieldrin-treated grass after exposure to sunlight ' and has been assigned
the structure A by most workers'1 ' •* although the structure B_ has also
been proposed. It is twice as active as dieldrin against Musaa domestica
and Aedes aegypti larvae. Relative to dieldrin, its acute toxicity
is higher for rats, mice, guinea pigs, and pigeons, less for domestic fowl
r fift i
and harlequin fish and about equal for beagle hounds. The amounts of
photodieldrin formed from dieldrin by sunlight does not significantly
increase the overall residues arising from the use of aldrin and dieldrin.
o
Irradiation of dieldrin (A-2537 A) in dilute hexane solution yields the
dechlorinated product (C_) . C. was found to be about five times as active
as dieldrin against mice (oral) but less active than dieldrin against
M. domestica. A number of aquatic microorganisms from silt and water samples
taken from Lake Michigan converted dieldrin to photodieldrin.
A number of soil microorganisms have been reported to be active in
the degradation of dieldrin. The soil fungus Trichoderma viride degraded
dieldrin into 4 major metabolites, but only one was unambiguously identified
f32l T71]
as 6.7-trans-dihydroxydihydroaldrin. J Aerobaoter aerogenes and
F72 731
several other soil microorganisms ' were studied, and it was found that
they hydrolyzed dieldrin to at least nine metabolites including 6.7-trans-
[741
dihydroxydihydroaldrin (D). Matsumura, et. al., reported on the breakdown
of dieldrin by a Pseudomonas species. Five major metabolites were isolated
and analyzed. One metabolite was identified as aldrin and the proposed -
structures for the other four metabolites correspond to E., F_, £, & H of
101
-------
FIGURE VII-3
ROUTES OF DIELDRIN DEGRADATION AND METABOLISM
6,7-trans-
dihydroxydehydroaldrin
OH
102
-------
Figure VII-3. A larger amount of undegraded dieldrin was also observed with the
metabolites. The soil fungus Mucor alternans did not degrade dieldrin in pure
culture nor in the soil samples.[33] Chacko, et al.,t21] also reported that
some soil organisms were incapable of degrading dieldrin.
Dieldrin has been classified as a highly residual compound. '
The various routes of dieldrin transport in and loss from soils were
studied, and the major pathways of dieldrin loss were volatilization
and sediment transport. However, in both the total and local sense, some
residue accumulation can occur and persist.
In a Louisiana estuary, the water, bottom sediment, and oysters
F821
were studied to determine the concentration of dieldrin. The data
showed that the bottom sediment and the oysters contain 3-4 ppb while the
water contains less than 1 ppb, reflecting the insolubility of dieldrin in
water.
3. Metabolism and Degradation of Malathion
The metabolism and degradation of malathion is complicated and
differs in various animal species, insects, fish or by microorganisms. The
possible metabolic breakdown products of malathion are shown in Figure VII-5.
r go 1
Malathion can be degraded by UV irradiation and gamma radia-
tion but no breakdown products were identified. Kearney quotes
reported evidence that malathion in soil cultures was degraded. The reaction
appears to be an initial non-enzymatic hydrolysis that gives what was tenta-
f 85]
tively identified as either a or 3 - malathion mono-acid. Chen, et al.,
reported that only a-malathion monoacid was biologically produced in rats.
Catalytic hydrolysis of malathion in soils to thiomalic acid,
dimethylthiophosphoric acid, diethyl thiomalate or diethyl mercaptosuccinate
was also reported. ' ' Konrad, et. al., ^ reported that malathion
degraded in soils occurred by a chemical mechanism catalyzed by adsorption
103
-------
and that diethyl mercaptosuccinate is a degradation product. However,
Bowman, et al.,^88^ disagreed with these findings and claimed that the
evidence of diethylmercaptosuccinate formation is not valid. Instead, they
reported minimal degradation of adsorbed malathion on montmorillonite soils
over a 3 to 5 day period. Walker has recently reported that malathion is
degraded by soil bacteria to malaoxon, malathion monoacid, malathion diacid,
[89]
dimethylphosphorothioate and dimethyl phosphorodithioate.
The biodegradation of malathion by microorganisms in streams was
studied by Randall & Lauderdale. They found that although aeration alone
is effective in the degradation of malathion, microbial action is a more
effective way of degrading malathion in an activated sludge system. Aerobic
microorganisms degraded malathion but no degradation products were identified.
f 911
Getzin & Rosefield1 J also reported that the heat labile, and alkali-
extractable fractions from some soils were capable of degrading malathion
within 24 hours. The identity of the breakdown products are still being
[92]
investigated. Matsumura & Bousch reported that the soil fungus
Tr-ichoderma vivlde and a bacteria of the Pseudomonas degraded malathion to
diethylmalate, demethyl malathion and a carboxyesterase product, the major
metabolite. Within 24 hours, the Pseudomonas degraded 98% of the malathion
applied while the T. viride degraded 75 to 90%. These microbial preparations
did not convert malathion to its more toxic analog, malaoxon. Lichtenstein,
[93]
et al., compared the persistence of organophosphorus pesticides in soils
and found that only 5% malathion residues could be recovered from the
soil 3 days after application. Malathion was reported to be less stable
than parathion and methyl parathion.
The lack of sufficient data on microbial degradation products of
malathion led to the consideration of breakdown of products reported in
Nigerian beetles, rice brans, maize and wheat grains. Dyte
104
-------
[941
and Rowlands reported that the formation of 0,0-dimethylphosphorodithioate,
0,0-dimethylphosphorothionate, dimethylphosphate, malathion mono-acid and
f 951
malathion di-acid. Rowlands and Clemente1 J found that in rice brans of
high oil and fatty acid content, both dimethyl phosphorothionate and dimethyl-
phosphor odithioate were found while in rice brans of low oil content, the
latter was the only metabolite detected.
From studies in maize and wheat grains, Rowlands reported that
malathion was degraded to dimethylphosphorodithionic acid (unstable and
degrades to phosphoric acid derivatives), malathion mono-acid, and malathion
di-acid. These products were formed by chemical and enzymatic hydrolysis.
It was also noted that the oxidations of malathion to malaoxon did not occur.
Malathion shows a pattern of metabolic selectivity which probably
accounts for the wide differential toxicity between insects and mammals.
It has been reported that the metabolism of malathion probably follows two
[97]
enzymatic routes, i.e., carboxyesterase or phosphatase degradation.
The points of degradation and cleavage of malathion are shown in Figure V1I-4
In the case where the proper oxidative system is present, malathion
is oxidized to malaoxon and then malaoxon can undergo a parallel degradation
route, as indicated in Figure VII-5.
The phosphorus containing metabolites that can be derived from
malathion are shown schematically in Figure VII-5.
4. Metabolism and Degradation of Abate
Streams and ponds in California and New Jersey, which have been
treated with a total of 1.0 Ib of Abate insecticides per acre, were studied
to determine the rate of disappearance of Abate. There was no apparent
accumulation of Abate in water or mud samples or at sampling stations down-
stream.[98]
105
-------
FIGURE VII-4
POINTS OF MALATHION DEGRADATION
CH0
CH3Oy
/ ° J
/ II *
P - S - CHC-0-C2H5
Cleavage at point (b) will give diethyl mercapto-succinate which can be
hydrolyzed to thiomalic acid.
HSCHCOOC2H5
hydrolysis
CH2COOC2H5
diethylmercapto-
succinate
HSCHCOOH
CH2COOH
thiomalic acid
106
-------
FIGURE VII-5
ROUTES OF MALATHION DEGRADATION AND METABOLISM
(CH30)2POSH
dimethyl
phosphorothionic
acid
CH30-P-SCHCOOC2H5
OH CH2COOC2H5
demethyl malathion
(CH30)2P-SH
dimethyl
phosphorodithionic
acid
(CH30)2PSCHCOOC2H5
CH2COOC2H5
malathion
S
n
(CH30)2P-S-CHCOOH
CH2COOC2H5
0
n
(CH30)2P-OH
dimethyl
phosphoric
acid
(CH30)2POSH
dimethyl
phosphorothionic
acid
0
II
(CH30)2PSCHCOOC2H5
CH2COOC2H5
malaoxon
0
u
(CH30)2PSCHCOOH
CH2COOC2H5
malathion mono-acid
S
n
(CH 0) P-SCHOCOOH
CH2COOH
malathion di-acid
malaoxon mono-acid
0
n
(CH 0) PSCHCOOH
CH2COOH
malaoxon di-acid
107
-------
There were no reported studies on microbial degradation products,
[99]
however, studies were reported on the metabolism of Abate in bean leaves
and in rats.'-100^ In the literature search on DDT, dieldrin, and malathion
on which studies have been conducted on pesticide metabolism in animals,
plants, insects, and by microorganisms, there was a wide overlap on the
metabolic products reported. The metabolic routes can vary, but the ultimate
end products formed were the same. Thus, perhaps, we can use the reported
degradation pathways of Abate in bean leaves and in rats as a working model.
Tritium labelled Abate was used in both studies reported. In
the bean leaves, intact Abate was the principal constituent of the residue
(70%) indicating a relatively high resistance to degradation. The major
degradation products reported were the sulfoxide derivative, and trace
amounts of the sulfone derivative, its unsymmetrical mono-oxono analog,
and the symmetrical dioxono analog of Abate. The glucosidic conjugates
4,4'-thiodiphenol, 4,4'-thiosulfinyldiphenol, and 4,4'-thiosulfinyldiphenol
were also found to increase with time. In rats, where fecal and urinary
routes are the major paths of elimination, the feces contained mainly
unchanged Abate together with the sulfoxide derivative and the phenolic
hydrolysis products while the urine contained mainly sulfate ester conjugates
of the phenolic hydrolysis products and trace amounts of unchanged Abate.
The metabolic route for Abate is shown in Figure VII-6. It appears
to follow two routes. Route a. is the principal metabolic route. The
reaction involves initial oxidation of the sulfide linkage, and subsequent
hydrolysis of the phosphate ester groups and glucosidic conjugation of the
phenolic hydrolysis products.
C. RESIDUAL LEVELS OF INSECTICIDES
In order to improve our understanding of the residue levels of
insecticides that currently exist on Cape Cod, a limited number of samples
of bottom mud, soil, and water were taken for pesticide analysis. To do
108
-------
FIGURE VII-6
ROUTES OF ABATE DEGRADATION AND METABOLISM
(CH30)2-P-0-
-0-P-(OCH3)2
S
n
(CH3)2-P-0-
-0-P-(OCH3)2
Sulfoxide
J'-n/
0
«
Sulfone
(CH30)2
11 /7~ "
-P-0-/ -S-
-0-P-(OCH3)2
Mono-oxo-sulfone
(CH30)2-P-0-
HO-
OH
4,4*-thiosulfonyldiphenol
(CH30)2-P-
S- >0-P-(OCH3)2
Mono-oxono analog
(CH30)2-P-0/'_VS-<' >-0-P-(OCH3)2 (CH30)2-P-0-//
-0-P-(OCH3)2
Dioxono
analog
4,4'-thiodiphenol
0
n
0-P-(OCH3)2 (CH30)2-P-0-
-0-P-(OCH3)2
4,4'-thiosulfinyldiphenol
109
-------
this, we chose locations that were near those investigated and described in
the biological impact section of this report. Based on their use in past
vector control programs on Cape Cod, the insecticides investigated were DDT,
dieldrin, and malathion. Abate, which had been used on Cape Cod for vector
control up until 1970 at low levels (0.01-0.2 Ibs) was not included in the
analysis scheme because it was not deemed likely that measureable residues
still existed. Also, various fuel oil type formulations were sprayed in the
region of interest but these are extremely difficult to distinguish from
background oils and were eliminated from the analytical program.
In performing this work, we recognized the desirability of looking
for basic chemicals and their degradation products, but our analyses were
limited to p,p'-DDT, dieldrin, malathion and the degradation products
p,p'-DDE and p,p-TDE for the following reasons:
• Many of the possible metabolites have not been positively
identified and confirmed;
• Easy-to-use analytical procedures are available for only a
few of the known metabolites;
• An attempt to establish an approach that would cover all known
metabolites would lead to an unweidly analyses scheme which would have been
impossible to follow within the budget and time limitations of this project.
The analyses of our samples for pesticide residues were performed
by Dr. Karl Deubert of the University of Massachusetts Agricultural Experi-
ment Station at East Wareham, Massachusetts. Dr. Deubert has worked
extensively in pesticide residue analysis and some of his unpublished data
on residue levels for DDT and dieldrin in salt water and mud at selected
sites on Cape Cod has been included in this report as a valuable reference
point for our study. Because he already had developed and calibrated the
110
-------
appropriate methodologies for this program, data was available for comparison
purposes from previous years. Thus, we were fortunate to be able to take
advantage of the prior experience of Dr. Deubert for this program.
It is important to recognize that the data obtained during this
program gives a qualitative overview of the current situation but is not
under any circumstances to be considered as being statistically significant.
To do so would have required the analyses of hundreds of samples—a task
which was beyond the present scope of this project. (The reasons for
requiring large numbers of samples are related to the wide variabilities
and many unknowns when sampling a salt marsh. Some of these are: variations
in soil type, whether vegetation roots are included in the sample, and
amount of water in the sample.)
All of the evidence available to us from the literature indicated
that the levels of organochlorine pesticides and/or organophosphorous com-
pounds should be less than a ppm in the salt marsh areas being studied
during this program. Thus, literature values for residues of p,p'-DDT
and/or dieldrin in soil samples seldom reach 1 ppm and then only when taken
soon after application of the pesticide. In fact, many results were well
below 0.1 ppm. ~ Earlier results on some mud samples from selected
points on Cape Cod had revealed the levels of DDT to be roughly 0.2-0.4 ppm
while the levels for dieldrin were 0.01-0.04 ppm. Similarly, the
levels of DDT and dieldrin in samples of salt water from marshes on Cape
\,
Cod had been less than 1 ppb.
As described in other parts of this report, neither DDT nor
dieldrin have been in use for control of mosquitos in salt marshes on Cape
Cod since 1966, whereas malathion and/or Abate, two organophosphate insecti-
cides had been applied until 1970. Thus, even though relatively stable, the
111
-------
chlorinated hydrocarbons DDT and dieldrin have not been in use for vector
control the past five years and therefore, would not be present in the marsh
at high levels due to this use. The organophosphates have been in use for
the last few years but are much more rapidly degraded and thus were not
expected to be found in the marsh. (It should be noted that as described
earlier both types of insecticides—organophosphorous and organochlorine—
will degrade to other products. In this study, we attempted to deal only
with the well described metabolites of DDT, namely TDE and DDE.) Although
not used for vector control purposes, other sources of contamination did
exist for each of these pesticides. For instance, dieldrin has been used
for pest control in cranberry bogs so that there has been the opportunity
for buildup of this pesticide in the Cape Cod area. In addition, many of
these pesticides may have been used by pest control operators for a number
of different reasons, any of which could have led to a burden on the local
environment.
To learn whether the pesticide levels were as low as anticipated,
a number of soil and water samples were collected from two areas in the Cape
and were analyzed for DDT, TDE, DDE, dieldrin and malathion. The samples
were collected on the same day (10/22/71) at the locations shown in Figure VI-1.
1. Experimental
a. Soil Samples
All soil samples were treated by a modification of Shell Chemical
Company method PMS 911/67 of 1969 as follows:
A representative sample was placed into an erlenmeyer flask and
enough water added to effect a slurry. Two ml of extraction solvent (n-hexane-
2 propanol 2:1) were added per gram of sample. Sample sizes ranged from
20-90 g. The samples were shaken vigorously for 20 minutes and then the
112
-------
hexane layer decanted into a separatory funnel. This extraction was repeated
twice more and the hexane layer was subjected to the cleanup procedure of
Kadoum.
b. Water Samples
Water samples were treated according to the following procedure:
One and a half liters were extracted successively with three
50 ml portions of n-hexane. After clean-up via the procedure of Kadoura,
this was then dried over Na2SOit concentrated by evaporation and analyzed
via gas chromatography.
c. Gas Chromatography
Gas chromatographic measurements were made on the hexane extracts
using the following experimental conditions:
Chromatograph: Barber-Coleman Model 5360
Column: Pyrex 6' x 4 mm I.D., 5% QF-1 on 100/120 Varaport 30.
Temperatures: Column 190°C
Injector 210°C
Detector 200°C
Carrier Gas: N2, approx. 100 ml per minute.
_9
Sensitivity: 1 x 10 amp., att. 2
Voltage: DC at which 0.5 mg dieldrin causes 25 percent FSD
at 1 x 10~9, att. 2
Recorder: 2 mv
Recovery experiments whereby known amounts of pesticides were
aaded prior to extraction were run at the same time as the samples. These
experiments indicated a recovery at 0.1 ppm of 87% for p,p'-DDT, 89% for
dieldrin, and 86% for p.p'-DDE.
113
-------
d. Thin Layer Chromatography
Plates: TLC plates were prepared at a nominal thickness of
0.25 mm using mallincrodt Silic AR TLC-7-6 as the
substrate.
Development: N-hexane as solvent in Brinkman sandwich apparatus
at 22°C. Development stopped when solvent front had
traveled 12 cm.
Visualization: Iodine vapors.
e. General
There are many chemical species which in the analysis procedures
can act in a similar manner to DDT, dieldrin and other pesticides. This is
because the potential interferring species have similar chemical properties
(solubility, reactivity, boiling point, etc.,) and thus are measured in the
final readout along with the compound of interest. In developing and
utilizing methods for the determination of pesticide residues, analytical
chemists take great care to minimize this difficult problem. However,
because of the complexity of the situation, compromises must be accepted
and a chance for error always exists. There are two ways to effectively
reduce this chance for error. One is to build many crosschecks and extra
steps into the procedure which makes it too complex and lengthy for routine
use. The alternative is to utilize more than one procedure for each sample
and thus make the measurement by two completely different approaches. This
too adds cost and time to the analysis.
Because of the limited time and budget available for our program,
it was impossible to perform the type of confirmatory experimentation which
would ensure that all of the data reported here is free from potential inter-
ferences. However, reasonable precautions were taken and we feel that our
data has the same validity as that found in the published literature.
114
-------
Nevertheless, it is important to recognize that many analyses for organo-
chlorine compounds are currently being challenged due to the discovery of
previously unrecognized interferences and similar possibilities exist for
the results reported in the following tables.
2. Results
The results of these analyses are shown in Table VII-1. It can be
seen that, as expected, the residue levels were low. (Malathion could not
be detected either b;, gas chromatography or thin layer chromatography in
any of the samples. The estimated detection limit for these samples in this
analysis scheme was 0.05-0.1 ppm.) Efforts were made to compare sample loca-
tion and residue level with regard to DD1, DDE, and dieldrin, but no correla-
tion could be found. As noted in Table VII-1, the residue values ranged from
-------
TABLE VII-1
PESTICIDE ANALYSES ON SOIL SAMPLES
Sample Sample Location
Code Marsh Area Specific
5 Bass Hole Gray's Beach Natural Drain into
Chase Garden Creek
5A
6 " " Chase Garden Creek
Near Above Drain
6A
60 " White's Brook Chase Garden Creek
600 " "
30 Herring River South of Rt #28 Herring River
Bridge
301 " " "
100 " North of Rt #28 Ditch 100 yds NE
Bridge of River
101
Sample
Bottom Sand
Soil from Bank
2' from Top
Bottom Sand
Soil from Bank
2' from Top
Bottom Mud
Soil from Bank
2' from Top
Bottom Mud
Soil from Bank
18" from Top
Bottom Mud
Soil from Bank
Pesticide Found
pp'DDT
0.02
0.01
<0.001
<0.001
<0.001
0.02
<0.001
0.07
0.04
0.04
pp'DDE
0.01
0.004
ND
0.003
0.004
0.008
0.001
0.01
ND
ND
(ppm)
Dieldrin
0.04
0.015
<0.001
0.006
0.006
0.009
0.01
0.03
0.04
0.01
12" from Top
-------
TABLE VII-1 (Cont.)
PESTICIDE ANALYSES ON SOIL SAMPLES
Sample
Code Marsh
Sample Location
Area Specific
Sample
Type
Pesticide Found (ppm)
pp'DDT pp'DDE Dieldrin
80
801
802
803
Herring River
North Road Near
Bell's Neck Rd.
Herring River, NE Bottom Mud
Buldge Downstream of
North Road Bridge
Drainage Ditch Near
Above
Soil from Bank
18" from Top
Bottom Mud
Soil from Bank
12" from Top
0.09
0.01
0.004
0.065
0.02
0.009
0.01
0.02
0.06
0.009
0.004
0.06
* ppm = parts per million
ND • not detected
AVERAGE 0.026 0.007 0.021
RANGE <0.001-0.09 ND-0.02 <0.001-0.06
-------
Even though slightly higher, these values do not represent a
major significant difference to those in the salt marsh channels.
3. Conclusions
Our results suggested that the insecticide levels in the two salt
marshes studied were quite low. Whether they relate to treatment in the
past of a "steady state" level due to other causes (spills, atmosphere
transport, pickup from the ocean, etc.), or are declining, is not known.
There is some other data available (even though sketchy) which
helps to clarify this point. Analyses were made of mud samples in the summer
of 1969 and again late in 1971 at four different locations on Cape Cod.
These results are given in Table VII-2. It will be noted in comparison
with the data in Table VII-1 that the levels of dieldrin in these locations
analyzed in 1969 and 1971 are not appreciably different from the values found
for 1971 (0.02-0.04 ppm for 1969, and up to 0.06 ppm in 1971). There might
be a trend to lower levels in 1971 but significance is questionable.
However, the DDT levels would appear to have decreased by almost
a factor of ten (0.2 to 0.026 ppm between 1969 and 1971). Whether this is
a real difference or an artifact of the analysis is not known. Additional
water samples collected from the same locations in 1969 and 1970 showed
higher dieldrin levels by factors of three to ten over those found in water
collected under this program in October of 1971. (All levels were extremely
low and it would be hazardous to consider this an important and significant
finding.) In addition, it is interesting to note that the data for DDT
does indicate some differences with possible signs of a trend (see Tables VII-3
and VII-4). Once again, these represent only a limited number of samples
so that developing a statistical significance is difficult. Also, a slight
modification in the analytical procedure was made between 1970 and 1971 (a
QF-1 column was used for the gas chromatography instead of DC-200, and this
118
-------
TABLE VII-2
ANALYSIS OF MUD SAMPLES
Location of Sample
South Side of Cape - salt pond
Same pond, different location
Same pond, different location
Creek on Upper Arm of Cape
River on Upper Arm of Cape
Creek on Upper Arm of Cape
AVERAGE
RANGE
Sample
0.2
0.2
0.4
0.2
0.3
0.2
0.3
0.3
0.1
0.02
0.3
0.3
0.2
0.3
0.2
0.2
0.2
0.2
Pesticide Found (parts per
DDT
1969 1971
Average Sample
0.02
0.3 0.01 0.02
0.09
0.03
0.2 0.04 0.04
0.02
0.03
0.2 0.03 0.02
0.02
0.03
0.3 0.08 0.03
0.06
0.02
0.2 0.02 0.02
0.03
0.04
0.2 0.01 0.03
0.06
0.2 0.03
0.2-0.3 0.01-0.08
million)
Dieldrin
1969
Average
0.04
0.03
0.02
0.04
0.02
0.04
0.03
0.02-0.04
1971
0.001
0.03
0.007
0.007
0.003
0.009
0.02
0. 001-0. C
-------
Date
10/71
Code
5
6
3
10
8
TABLE VII-3
ANALYSIS OF WATER SAMPLES (1971)
Location
Bass Hole Marsh - Drain into Chase Garden Creek
Bass Hole - Main Channel of Chase Garden Creek
Herring River - Main Channel
Side Ditch 100 Yards from Herring River
Herring River - Main Channel
AVERAGE
Pesticide
Found (ppb)*
DDT
0.01
0.005
0.005
0.005
0.005
Dieldrin
0.01
0.005
0.005
0.005
0.010
0.006
0.008
* ppb » parts per billion
-------
N3
Code
A
B
C
D
E
F
TABLE VI1-4
PESTICIDE LEVELS IN SELECTED WATER SAMPLES
Location
Pond on South Side of Cape
Same Pond - Different Local
Same Pond - Different Local
Creek on North Arm
River on North Arm
Creek on North Arm
AVERAGE
Pesticide Levels Found (parts
DDT
1969
Range
0.07-0.4
:ion 0.04-0.4
:ion 0.04-0.4
0.01-0.07
0.01-0.8
0.04-0.8
Average
0.3
0.2
0.2
0.3
0.2
0.3
*
per billion)
Dieldrin
1970
0.09
0.2
0.1
0.1
0.1
0.09
1971 1969
Range
0.006 0.01-0.04
0.01-0.04
0.01-0.06
0.009 T -0.07
0.005 0.01-0.09
0.005 T -0.05
Average
0.02
0.03
0.03
0.02
0.04
0.02
1970
0.02
0.02
0.05
0.009
0.04
0.06
1971
0.006
0.01
0.008
0.004
0.25
0.1
0.006
0.03
0.03 0.007
* T = trace.
-------
may account for the differences. However, it seems appropriate to recognize
that this trend might be real. In this regard, Woodwell, et. al.,
recently concluded that DDT levels in the biosphere are slowly decreasing
from their maximum levels which occurred in the mid-1960's as a result of
the widespread use of DDT during that period. Our data from work conducted
in Cape Cod salt marshes suggests that DDT levels have decreased between
1969 and 1971 and tends to support the Woodwell conclusions.
In any case, in order to determine whether these interesting
tentative observations are valid would require a much more comprehensive
program whereby more samples could be examined in greater detail so that
conclusions which were statistically sound could be reached.
122
-------
D. GLOSSARY OF TERMS
1. Insecticides
Dieldrin - 1,2,3,4,10,10-hexachloro-6,7-epoxy-l,4,4a,5,6,7,8,8a-octahydro-
1,4-endo-exo-5,8-d imethanonaphthalene.
Malathion - 0,0-dimethyl S-(l,2-dicarbethoxyethyl)phosphorodithioate.
Abate - 0,0,0",0'-tetramethyl 0,0'thiodi-p-phenylene phosphorothioate.
2. DDT. Metabolites
DDT - 1,1,1 trichloro - 2,2-bis (p-chlorophenyl) ethane.
ODD (TDE) - 1,1-dichloro - 2,2-bis(p-chlorophenyl) ethane.
DDE - 1,1-dichloro - 2,2-bis (p-chlorophenyl) ethylene.
DDMU - 1-chloro - 2,2-bis (p-chlorophenyl) ethylene.
DDMS - 1-chloro - 2,2-bis (p-chlorophenyl) ethane.
DDNU - 2,2-bis (p-chlorophenyl) ethylene.
DDNS - 2,2-bis (p-chlorophenyl) ethane.
DDA - bis (p-chlorophenyl) acetic acid
DBF - 4,4'-dichlorobenzophenone.
Dicofol - 1,1,1 trichloro - 2,2-bis (p-chlorophenyl) ethanol.
_ bis (p-chlorophenyl) methane.
_ bis (p-chlorophenyl) methanol.
123
-------
BIBLIOGRAPHY
1. Crosby, D.G. Pesticide Reviews, 25_, 1-12 (1969).
2. Kearney, P.C., & C.S. Helling. Residue Rev., 25_ 25-44 (1969).
3. Pramer, D. Environment, 13_, 42-46 (1971).
4. Stojanovic, B.J. & F. Hutto. Presented before the "Pesticides and Public
Health: Introductory Course," EPA, Division of Pesticide Community
Studies, Atlanta, Georgia, May 11-14, 1971.
5. Broker, W. Westfal. Bienenztg. , 67_, 252 (1954).
6. Fleck, E.E., & H.L. Haller. J. Am. Chem. Soc., 71^, 1034-36 (1949).
7. Roburn, J. Chem & Ind., 1955-56 (1966).
8. Sherman, V.W., R. Evans, E. Nesyto, & C. Radlowski. Nature 232,
118-19 (1971).
9. Fleck, E.E. & H.L. Haller. J. Am. Chem. Soc. 66_ 2095 (1944).
10. Ibid., 6£, 142-3 (1946).
11. Lopez-Gonzalez, J.D. & C. Gonzalez-Gomes. Anales Quin., 66, 271-82 (1970),
12. Lopez-Gonzalez, J.D. & C. Valenzuela-Calahorro. J. Agr. Food Chem 18,
520-23 (1970)
13. Swoboda, A.R., et. al. Environ. Sci. Technol. _5, 141-5 (1971).
14. Lord, K.A. J. Chem. Soc., 1657-61 (1948).
124
-------
15. Nash, R.G., & W.G. Harris. Symposium American Society of Agronomy,
New York, August 15, 1971.
16. Anonymous. Science News, 94. 642 (1968).
17. Dimond, J.B., et. al. Can. Entomologist, 102, 1122-30 (1970).
18. Focht, D.D. & M. Alexander. J. Agr. Food Chem. , 19_, 20-2 (1971).
19. Kokke, R. Nature, 226. 977-8 (1970).
20. Burge, W.D. J. Agr. Food Chem., 19_, 375-8 (1971).
21. Chacko, C.J., J.L. Lockwood, & M. Zabic. Science, 154, 893-5 (1966).
22. Guenzi, W.D. & W.E. Beard. Science 156_, 1116-17 (1967).
23. Ibid. Soil Sci. Soc. Am. Proc., 32_ 533-4 (1968).
24. Johnson, B.T., et. al. Science, 157, 560-61 (1967).
25. Ko, W.H. & J.L. Lockwood. Can J. Microbiol., _14» 1069-73 (1968).
26. Langlois, B.E. J. Dairy Science, 5_0, 1168-70 (1967).
27. Mendel, J.L., A.K. Klein, J.T. Chen & M.S. Walton. JOAC, 50, 897-903 (1967)
28. Patil, K.C., F. Matsumura & G.M. Boush. Applied Microbiology, 19,
879-81 (1970).
29. Plimmer, J.R. , P.C. Kearney, D.W. Von Endt, J. Agr. Food Chem., 16^
594-7 (1968).
125
-------
30. Wedemeyer, G. Science, 152, 647 (1966).
31. Ware, G.W. & G.C. Roan. Residue Rev., 33., 15-45 (1970).
32. Matsumura F. & G.M. Boush. J. Econ, Entomol., £1. 610-12 (1968).
33. Anderson, J.P.E., E.P. Lichtenstein, and W.F. Wittingham. J. Econ.
Entomol., 6^3, 1595-99 (1970).
34. Focht, D.D. and M. Alexander. Science, 170, 91-92 (1970).
35. Ibid. Applied Microbiology, 20_, 608-11 (1970).
36. Wedemeyer, G. Appl. Microbiol., 15, 1494-5 (1967).
37. Ibid. 569-74 (1967).
38. Lichtenstein, E.P., T.W. Fuhremann, and K.R. Schultz. J. Agr. Food Chem.,
19_, 718-721 (1971).
39. Deubert, K.H. & B.M. Zuckermann. Pesticides Monit. J., 2^, 172-5 (1969).
40. Chisholm, R., et. al. J. Econ. Entomol., 43, 941-2 (1950).
41. Ginsburg, J. J. Agr. Food Chem., _3, 322-5 (1955).
42. Guenzi, W.D. & W.E. Beard. Soil Sci. Soc. Am. Proc., 34, 443-7 (1970).
43. Harris, C.R. J. Econ. Entomol., £2_, 1437-41 (1969).
44. Ko, W.H., & J.L. Lockwood. Can. J. Microbiol., 14, 1075-8 (1968).
45. Lichtenstein, E.P. & Schultz, K.R. J. Econ. Entomol., 52, 124-31 (1959).
126
-------
46. Lichtenstein, E.P., L.J. dePew, E.L. Eshbaug & J.P. Sleeman. J. Econ
Entomol., _5.3, 136-42 (1960).
47. Mulla, M.S. J. Econ. Entomol., 53, 650-55 (1960).
48, Peterson, J.R. Dissert. Abst, Intern., 31, (3): 1010B (1970).
49. Sferra, P.R. J. Econ. Entomol., 49, 414-15 (1956).
50. Smith, M.S. Nature, 161, 246 (1948).
51. Ware, G.W., B.J. Estesen, & W.P. Cahill. Pest. Monit. J., 2_,
129-32 (1968).
52. Hamelink, J.L. Dissert. Abst. Intern., 3£, (12, Ptl) 5312B-3B (1970).
53. Johnson, L.G., & R.L. Morris. Pesticides Monit. J., 4_, 216-9 (1971).
54. Matsumura, F. , K.D. Patil, & G.M. Boush. Nature 230. 325-6 (1971).
55. Miskus, R.P., D.P. Blair, & J.E. Casida. J. Agri. Food Chem.,
13, 481 (1965).
56. O'Connor, R.C. Symposium Am. Soc. Agronomy, N.Y., August 15, 1971.
57. Seba, D.B., E.F. Corcoran. Science, 171. 928 (1971).
58. Burnett, R. Science, 174. 606-8 (1971).
59. Yule, W.N. & A.D. Tomlin. Bull. Environ. Contain. Toxicol., 5_,
479-88 (1970).
60. Metcalf, R.L., G.K. Sangha, & I.P. Kapoor. Environ. Sci. & Technol.,
5, 709-13 (1971).
-------
61. Kapoor, I.P., R.L. Metcalf, R.F. Nystrom & G.K. Sangha. J. Agri. Food
Chem., 113, 1145-52 (1970).
62. Harrison, J.E., et. al. Science, 170, 503-8 (1970).
63. Eberhardt, L.L., R.L. Meeks, & T.J. Peterlo. Nature, 230, 60-2 (1971).
64. Kallman, B.T., & A.K. Andrews. Science, 141, 1050-1 (1963).
64A. Woodwell, G.M., P.P. Craig, & H.A. Johnson. Science, 174, 1101-7 (1971).
65. Parzons, A.M., and D.J. Moore, J. Chem. Soc., 2026-2031 (1966).
66. Roseva, J.D., D.J. Sultherland, and G.R. Lumpton. Bull. Environ. Cont.
and Toxic., ±, 132-140 (1966).
67. Harrison, R.B., B.C. Holmes, J. Roburn, and J.O.C. Tatton. J. Sci. Food
Agri., 18, 10-15 (1967).
68. Robinson, J.A., U.K. Brown, and A. Richardson. Food & Cosmetic Toxicol.,
5_, 771-79 (1967).
69. Robinson, J.A., J.A. Richardson, B. Bush, and K.E. Elgar. Bull Environ.
Cont. and Toxic., 1^, 127-132 (1966).
70. Henderson, G.L., and D.G. Crosby. J. Agr. Food Chem., 15, 888-93 (1967).
71. Wedemeyer, G. Appl. Microbiol. , .L6_, 661-2 (1968).
72. Anonymous. World Rev. Pest. Cont., ]_, 68-9 (1968).
73. Matsumura, F and G.M. Boush. Science, 156, 959-61 (1967).
128
-------
74. Matsumura, F., G.M. Boush, & A. Tai. Nature, 219. 965-67 (1968).
75. Caro, J.H., & A.W. Taylor. Ibid., 379-84 (1971).
76. Eye, J.D. J. Water Pollut. Cont. Fed. Suppl. , 40_, R 316-32 (1968).
77. Lichtenstein, E.P., J.P. Anderson, F.W. Fuherraann, & K.R. Schultz.
Science, 159. 1110-1 (1967).
78. Saha, J.G. 6. Y.W. Lee. J. Econ. Entomol., i6_3, 670-1 (1970).
79. Spencer, W.F., M.M. Cliath, & W.J. Farmer. Soil Sci. Soc. Am.
Proceedings, _33_> 509-11 (1969).
80. Thompson, A.R., C.A. Edwards, M.J. Edwards, & K.I. Beynon. Pesticide
Sci., !_, 174-8 (1970).
81. Winnett, G. & J.P. Reed. Pest. Monit. J. , .2, 133-6 (1968).
82. Rove, D.R., et. al. Pesticides Monit. J., 4_, 177-83 (1971).
83. Okado, K., & K. Nomura. Nippon Nogeiku Kaishi, _3£ 240-44 (1964)
[Ca 6a, 4891 (1964)].
84. Lippold, P.C., et. al. J. Econ. Entomol., 6£, 1509-10 (1969).
85. Chen, P.R., W. Tucker, W- Dauterman. J. Agr. Food Chem., 17, 86-90 (1969)
86. Konrad, J.G., Gesters, G. Armstrong, D.E. Soil Sci. Amer. Proc., 33
259 (1969).
87. Konrad, J.G. Dissertation Abst. Intern., _30_ (1) 23B-4B (1969).
129
-------
88. Bowman, B.T., R.S. Adams, & S.W. Fenton. J. Agr. Food Chem,, 18
723-7 (1970).
89. Walker, W.W. Symposium Am. Soc. Agronomy, N.Y., August 15, 1971.
90. Randall, C.W., M. Asce, & R.A. Lauderdale. Proceedings Am. Soc. Civil
Engineers, 6^ 145-156 (1967).
91. Getzin, L.W., & I. Rosefield. J. Agr. Food Chem., 16^ 598-601 (1968).
92. Matsumura, F. & G.M. Boush. Science, 153, 1278-80 (1966).
93. Lichtenstein, E.P. J. Econ. Entomol., 57, 618 (1964).
94. Dyte, C.E., & D.G. Rowlands. J. Stored. Prod. Res., 4_, 157-73 (1968).
95. Rowlands, D.G., & J.E. Clements. J. Stored. Prod. Res., 1_ 101-3 (1965).
96. Rowlands, D.G. J. Sci. Fd. Agric. , 15_, 824-9 (1964).
97. O'Brien, R.D. Insecticides: Action & Metabolism, Academic Press, N.Y., 1967.
98. Bowman, J.S. , & E.J. Orloski. Mosquito News, 25, 557 (1966).
99. Blinn, R.C. J. Agr. Food Chem., .16, 441-5 (1968).
100. Blinn, R.C. Ibid., 17^ 118-22 (1969).
101. Gish, C.D. Pesticides Monitoring Journal, _3, No. 4, 241 (1970).
102. Fahey, J.E., et. al. Pesticides Monitoring Journal, 1L, No. 4. 31 (1968).
130
-------
103. Trautman, W.L., et. al. Pesticides Monitoring Journal, 2^ No. 2, 97
(1968).
104. Deubert, K.H. Unpublished results.
105. Kadoum, A.M. Bull, Environ. Contain. Toxicol., .2, 264 (1967); .3 65
(1968).
131
-------
VIII. LAWS AND REGULATIONS GOVERNING PESTICIDES
A. FEDERAL REGULATION OF PESTICIDES
1. Organizations
a. Environmental Protection Agency
The Environmental Protection Agency (EPA) has responsibility
for establishing and enforcing pesticide standards, for monitoring and
analyzing the environment, for conducting research and demonstrations re-
lated to the environment and assisting state and local governments in
establishing and carrying out pollution control programs. It is responsi-
ble for carrying out anti-pollution policies and executing many of the
tasks necessary to effectively control pollution from all sources.
The EPA combined the major federal pollution control programs
previously located in five separate federal agencies. These included the
Federal Water Quality Administration from the Department of the Interior
(Interior); the National Air Pollution Control Administration, The Bureau
of Solid Waste Management, Bureau of Water Hygiene, and Bureau of
Radiological Health from the Department of Health, Education and Welfare
(HEW); pesticides standards and research from HEW and Interior; pesti-
cides registration from the Department of Agriculture; the Federal
Radiation Council from the Executive Office of the President; and environ-
mental radiation standards from the Atomic Energy Commission.
b. Department of Health, Education and Welfare
The Department of Health, Education and Welfare has responsi-
bility under the Federal Food, Drug and Cosmetic Act for monitoring and
132
-------
enforcing standards for pesticides in or on agricultural commodities and
processed food but EPA establishes these standards. The Department is
also responsible for protecting the public from occupational and environ-
mental hazards and from other public health problems including diseases
transmitted by vectors.
c. Department of Agriculture
The Department of Agriculture is responsible for research on
the effectiveness of pesticides and for various other research, infor-
mation, education, and regulatory programs to protect human beings, crops,
livestock, forests, stored products, and structures against insects, weeds,
fungi, and other pests.
d. Department of the Interior
The Department of the Interior is responsible for the con-
servation of wild birds, fish, mammals, and their food organisms in the
environment, and it is generally responsible for research on all factors
affecting fish and wildlife. However, authority for research to deter-
mine the specific effects of pesticides on birds, fish, and other wildlife
rests with EPA.
e. Other Organizations
There are numerous other federal government organizations which
influence the use of pesticides for vector control. These include the
Federal Working Group on Pest Management, Hazardous Materials Advisory
Committee, Armed Forces Pest Control Board, the Interior Intra-departmental
Pesticides Working Group, and the Agriculture Intra-departmental Pesti-
cides Working Group.
133
-------
2. Federal Legislation
Federal laws that most directly deal with the use, sale, trans-
portation, and application or effects of pesticides and other hazardous
substances include the following:
a. Water Quality Improvement Act, P.L. 91-224, 84
Stat. 91 (1970).
b. Environment Quality Improvement Act, Public Law
91-224, 84 Stat. 114 (1970).
c. Clean Water Restoration Act, P.L. 89-733, 80 Stat.
1246 (1966).
d. Water Quality Act, P.L. 89-234, 79 Stat. 903 (1965).
e. Federal Water Pollution Control Act, P.L. 87-88,
75 Stat. 204 (1961).
f. Water Pollution Control Act, P.L. 84-660, 70 Stat.
498 (1956).
g. Water Pollution Control Act, P.L. 82-579, 66 Stat.
755 (1952)
h. Water Pollution Control Act, P.L. 80-845, 62 Stat.
1155 (1948).
i. Fish and Wildlife Coordination Act, P.L. 85-624,
16 USC 661 (1958).
j. Federal Insecticide, Fungicide, and Rodenticide Act,
7 USC 135, 61 Stat. 163 (1919).
Important executive orders dealing with pesticides or their effects include:
• Executive Order 11507-Prevention, Control, and Abatement
of Air and Water Pollution at Federal Facilities,
4 February 1970.
134
-------
• Executive Order 11288-Prevention, Control and Abatement
of Water Pollution by Federal Activities, 2 July 1966.
These laws and executive orders, when coupled with executive regulations
and procedures, constitute the national framework within which vector
control programs are undertaken in the northeast states.
3. Federal Cases
Several pesticide cases have been heard that involve federal
law or federal agencies or officials in recent years. To date, these
cases have mostly dealt with procedural issues. For example, in Nor-Am v.
Hardin, 1 ER 1460 (USCA 7th) the court held that the —
Manufacturer of mercury fungicide, use of which was ordered
suspended by Secretary of Agriculture under Federal
Insecticide, Fungicide and Rodenticide Act, 7 USC 135, based
on a single abnormal incident and without a hearing, was
entitled to federal court review on a claim that the order
was arbitrary and capricious, since the order was the final
determination of the matter of imminent hazard to the
public.
Other important cases are Environmental Defense Fund v. HEW, 1 ER 1341
(USCA, DC) and Environmental Defense Fund v. Hardin, 1 ER 1347 (USCA, DC).
B. MASSACHUSETTS REGULATION OF PESTICIDES
1. Organizations
a. Pesticide Board
The Commonwealth of Massachusetts established a Pesticide Board
in the Department of Public Health in 1962. The members of the board are
the Commissioners of Public Health (Chairman), Natural Resources, Agri-
culture, and Public Works, the Director of the Division of Fish and Game
and the Chairman of the State Reclamation Board or their designees, and
135
-------
five members appointed by the governor. The appointive members serve for
terras co-terminous with the governor.
The board may adopt and make provisions to enforce such rules
and regulations as it determines are necessary to protect the public
interests in the soils, waters, wetlands, wildlife, agriculture, and other
natural resources of the Commonwealth. It is also to undertake a contin-
uous study of methods of applying and using pesticides, the effects of
such applications and uses, and to publish the results of this work from
time to time.
Upon written request from the Pesticides Board, its financial
needs are included by the Commissioner of Public Health in the budget of
the Department of Public Health.
The board is required to meet at least four times per year and
may also meet when called by the Chairman or upon written request by any
two members. Board decisions are rendered by a majority vote and imple-
mented by the Commissioner of Public Health. However, other governmental
agencies, when authorized by the board in writing, can carry out certain
provisions of the law and the rules and regulations promulgated by the
board.
b. Reclamation Board
The Commonwealth of Massachusetts established a State Reclamation
Board under Chapter 252 of its General Laws. The members of the board are
one employee of the Department of Public Health, one employee of the
Department of Agriculture, and a third member designated jointly by the
heads of both departments. These members must be approved by the governor
136
-------
and the Governor's Council. The board is under the administrative control
of the Department of Agriculture.
The board is to make determinations of the usefulness and
necessity of improving lowland by draining or removal of obstructions in
streams or rivers, and the necessity of eradicating mosquitoes in any
infested area. The board is to consider the agricultural or industrial
uses made possible on such land, the protection of the public health, the
utilization of any deposits in such land, and other purposes made possible
by any proposed treatments.
c. Water Pollution Control Division, Massachusetts Department
of Natural Resources
The Commonwealth of Massachusetts established a Water Pollution
Control Division under the control of the Water Resources Commission in
the Department of Natural Resources under Chapter 21 of the General Laws
as amended in 1966, 1967, 1969, and 1970. The division has a director
appointed by the commission and its work is supervised by the commission.
The director employs an assistant director, division legal counsel, and
other necessary professional, technical, and clerical personnel, subject
to the approval of the commission.
The division's responsibilities are to establish programs for
the prevention, control, and abatement of water pollution and to other-
wise enhance the quality and value of the water resources of the
Commonwealth. Among its responsibilities, as cited in the law, are the
establishment of water quality standards, periodic examination of water
quality, and the submission of proposed water pollution abatement
137
-------
districts, with the approval of the commission, to cities and towns. Such
districts are established after .approval by those in the area proposed
for inclusion in the district and each becomes a body politic and corporate
with a governing district commission.
Also, under the law, the members of the Water Resources Commission
and the Commissioner of the Department of Public Safety sit as a board to
control the handling and disposal of certain chemical and hazardous wastes.
The board, after public hearing, may adopt rules and regulations
to protect the public and the environment from the effects of handling
and disposal of such chemicals and wastes. The law states that these
repponsibilities are not to diminish or interfere with the responsibili-
ties of any other agency.
2. Massachusetts Laws, Regulations, and Regulatory Processes
a. Hazardous Substances Act. Chapter 94B (1960)
The Hazardous Substances Act places the responsibility for con-
trol of hazardous substances in the Department of Public Health under
the direction of the commissioner. The commissioner may formulate reasonable
rules and regulations declaring any substance to be hazardous when he
finds it satisfies the definition set out by the law.
(1) Registration. Every pesticide distributed, sold,
offered for sale in the Commonwealth, delivered for transportation or
transported in intrastate commerce, or between points within the Commonwealth
through any point outside the Commonwealth, must be registered with the
Director of the Food and Drug Division, and such registration must be
renewed annually.
138
-------
The registrant files with the commissioner a statement includ-
ing his name and address, and the name and address of the person whose
name will appear on the label; the name of the pesticide; a complete copy
of the labeling for the pesticide and a statement of all claims to be
made for it, including directions for use. If requested by the commis-
sioner, a full description of the tests made and their results must also
be filed.
It is unlawful to distribute, sell, or offer for sale in the
Commonwealth or to deliver or transport any pesticide not registered, or
for which different claims are made or for which the composition differs
from that set out in connection with its registration. The commissioner
has the authority to revoke or modify any registration granted under
Chapter 94B if the Pesticide Board finds that continuation of the regis-
tration would constitute a hazard to the public health, fish, wildlife,
shellfish, or other natural resources of the Commonwealth. When such a
claim is made, the commissioner notifies the registrant in writing of the
effective date of the revocation of the registration. An appeals proced-
ure is available to the registrant.
(2) Labeling. Pesticides must be labeled with the name and
address of the manufacturer, registrant, or person for whom it was
manufactured, the name, brand, or trademark under which the substance is
sold, the net weight, and the measure of the content. Any pesticide which
contains a substance highly toxic to man must be labeled with a skull and
crossbones and the word "poison" prominently in red on a background of
contrasting color, and the antidote.
139
-------
The act prohibits any alteration of the label on a hazardous
substance while any portion of the substance is still in the container and
makes it unlawful to receive or deliver a misbranded package containing a
hazardous substance. A hazardous substance in a container used for food,
drug, or cosmetics and still bearing its regular label cannot be sold or
given away. Any such use of containers results in the hazardous substance
being misbranded. A misbranded package, when manufactured with the intent
that it be distributed or sold, is to be embargoed by a representative of
the Division of Food and Drugs and submitted to the jurisdiction of the
courts, except when intended for export to any foreign country and labeled
according to the laws of the foreign country and to show that it is
intended for export.
(3) Enforcement. The commissioner and his designees are
authorized to make inspections to enforce the provisions of Chapter 94B
and any rules and regulations the commissioner promulgates under that
chapter. They are to have access at reasonable times to any premises where
they suspect the presence of any hazardous substance that is misbranded.
Persons manufacturing, storing, receiving, or holding hazardous
substances are to provide the director or his inspectors with access to
all records showing any movement or holding of such substances during or
after movement, and the quantities involved and are to allow these records
to be copied.
Any person who obstructs the director or his inspectors from
entering premises where hazardous substances are kept or does not comply
with the provisions for providing for records and copying is subject to
punishment by a fine of not more than $2000 or imprisonment of up to six
months or-both.
140
-------
The commissioner may authorize formal complaints to appropriate
authorities or the superior court where it appears that any provisions of
the pesticides law were violated. Except for special provisions in the
case of certain violations of the law, a first offense is punishable by a
fine of not less than $150 or more than $200. For a second or subsequent
offense, the fine is not less than $200 or more than $1000, or imprisonment
of not more than 90 days, or both.
(4) Licenses for Pesticide Sales. No wholesaler or distributor
other than a person selling at retail level may sell, offer to sell, dis-
tribute, or deliver a pesticide in the Commonwealth unless he has a license
to do so from the Department of Public Health. Such licensees are to
supply the Pesticide Board with information concerning the quantities of
certain pesticides, the use of which has been regulated by the board or
which are being considered for regulation, that were sold or delivered in
the Commonwealth and the names and addresses or such purchasers or recipients
upon the board's request.
(5) Appeals and Administrative Procedures. The law sets out
procedures for correcting any discrepancies in labeling or claims for a
pesticide and for formally challenging decisions made by the commissioner.
(6) Embargo. Any pesticide which is adulterated or misbranded
or which has not been registered under the provisions of Chapter 94B or
which does not bear on its lable the information required by the pesticide
law, or which is a white powder pesticide, and not colored as required by
the pesticide law can be embargoed.
(7) Pesticide Board. The duties and powers of the Pesticide
Board are defined in the act.
141
-------
In general, the power delegated to the Pesticides Board to con-
trol application and use of pesticides is broad. The board can adopt and
amend regulations controlling the storage, transportation, use, and
application of pesticides that it deems necessary for protecting public
health and public interests in the environment. Before adopting these
regulations, however, the law requires that the board consult with the
scientific community, the pesticide industry, pesticides applicators and
users, and the general public.
The board is restricted from requiring farmers or persons apply-
ing pesticides on or under any structure to be licensed but these persons
may be required by the board to design a statement pledging to use pesti-
cides only as authorized by the board. The law provides that anyone using
an aircraft to apply pesticides must be licensed.
Violators of the rules and regulations issued by the board are
subject to a fine up to $100 for the first offense and a fine of up to
$500 for subsequent offenses.
The Pesticides Board adopted rules and regulations on March 12,
1964, and amended the same on March 29, 1967; May 13, 1971; and May 26,
1971. The rules and regulations require the restriction of all pesticides
used or applied in the Commonwealth to be registered with the Division of
Food and Drugs, Department of Public Health. Each pesticide is registered
in terms of uses, rates of application, and intervals of use, and the
regulations require that any pesticide will be used only for registered
uses and will not exceed registered dosages and intervals.
All uses of pesticides on surface, near subterranean, or in the
watershed area for public water supplies must be approved by the board
upon the recommendation of the Department of Public Health.
142
-------
Disposal of pesticides is to occur only in a disposal area
assigned by local boards of health and operated according to relevant
Massachusetts laws, in municipal incinerators, or in other devices approved
by the Department of Public Health. If the materials are disposed of by
burial, such disposal must insure that contamination of ground or surface
water is held to a minimum and that the materials will not be disturbed by
subsequent activities in the area.
Burning of certain pesticides is authorized if the local fire
department is contacted and if in compliance with regulations of local
boards of health or the Metropolitan Air Pollution Control District.
Methods of disposal of pesticides containers are not specified
in the board's regulations, but instead fall under rules and regulations
established by the Department of Public Health. Treatment of pesticides
containers prior to their use for limited purposes is also regulated by the
Department of Public Health.
Persons applying or handling pesticides are individually responsi-
ble for their own safety and safety procedures.
Any application of pesticides to the land of another must be
made in the presence of a person licensed by the board. Requirements for
licensing include experience at the operational level of pesticides appli-
cation under a person holding a supervisory license or such experience in
combination with specified educational qualifications and successful
completion of an examination conducted under the direction of the board.
Licenses are issued for a two-year period or temporarily, at the discretion
of the board.
143
-------
Non-residents may apply pesticides in the Commonwealth if they
are licensed in another state under a law requiring similar qualifications
of the licensee and if the other state grants reciprocity to applicators
licensed in Massachusetts.
At least one supervisory license is required for each business
and governmental entity that applies pesticides to the land of another.
A supervisory or operational licensee must be present wherever and whenever
pesticide applications are made.
The board may suspend or revoke any license granted under its
regulations following a hearing before the board if it is demonstrated that
the licensee failed to observe any board rule or regulation or any law
relating to pesticides.
Pesticide applications by licensed persons from aircraft must
be reported to the board within seven days. All other applications by
licensed persons must be recorded so that, upon request of the board, the
following data may be made available: area treated, pesticide formulation
used, dosage applied, method of application, date(s) of application,
target organisms, persons licensed by the board who planned and executed
the application, and any difficulties encountered which may have produced
hazards.
The Pesticide Board has acted to regulate the use and appli-
cation of certain pesticides as follows:
...pesticides (1) which are persistent in the environment;
(2) which accumulate as the pesticide per se or its
metabolites or degradation products in plant or animal
tissue or products and which may be transferred to other
forms in life; (3) which are translocated from the point of
application to points where they do not serve a useful
144
-------
purpose, and (4) which by virtue of this persistence,
accumulation or translocation create a risk of harmful
effects on organisms other than the target organisms,
or other pesticides with regard to which the board finds
that regulation is necessary in order to protect the
public wealth and the public interests in the soils,
waters, forests, wetlands, wildlife, agriculture and other
natural resources of the Commonwealth. It is the inten-
tion of the Pesticide Board to repeal any use permitted
herein when feasible non-persistent substitutes for these
pesticides and uses become available.
The board has ruled that DDD (IDE), aldrin, endrin, heptachlor,
and marine-fouling paints which contain the substance mercury in any form
or compound cannot be used or applied in Massachusetts. It has restricted
the use and application of dieldrin, chlordane, BHC, 2,4,5-T, DDT, and
toxaphene. Of these pesticides, dieldrin, 2,4,5-T, and DDT cannot be used
or applied without a permit from the board and then only subject to any
restrictions set out in the permit. Such a permit must be displayed before
these pesticides can be purchased.
The Chairman of the Pesticide Board may issue a permit allowing
the limited application of restricted pesticides to control dangers to
the public health, a recently introduced pest, or where there is demon-
strated public necessity for their use.
b. Mosquito and Greenhead Fly Control, Ch. 252 (1929)
(1) The Legal Framework. The Chapter 252 authorizes the
Reclamation Board to undertake activities to improve lowlands and to con-
trol mosquitoes and greenhead flies. The board may authorize improvement
activities only if state or local governmental entities and/or individual
proprietors petition the board to allow improvements that will help attain
the objectives cited in the law. If the proposed improvements appear
advisable to the board, it must give public notice of the petition and the
145
-------
date of the hearing before the board. If there are no individual propri-
etors involved in the petition, and the board determines that the improve-
ments should be undertaken, the construction and maintenance of the
proposed improvements are undertaken without the formation of a reclamation
district. Instead, all persons and governmental entities benefited by the
project-are notified by the board as to the estimated expenses and main-
tenance costs for the project. Upon receipt of adequate funds, the board
appoints one or.more commissioners and authorizes them to carry out and
maintain the improvements.
If the individual proprietors have joined in the petition, the
board, after determining that the proposed improvements should be under-
taken, must decide whether to organize a reclamation district to carry out
and maintain the improvements. If it decides that a district should be
organized, it appoints commissioners and authorizes them to form a
reclamation district and to carry out and maintain the improvements.
A reclamation district is formed by the newly sworn commissioners
by calling a meeting of the owners of the land to be improved, indicating
the matters upon which action is to be taken at the meeting. A majority
of interest in value or area, including valid proxies, is required for
the meeting to act. If such majority is present, the meeting may vote on
whether to accept Sections 1 through 14B of Chapter 252 of the General
Laws of the Commonwealth of Massachusetts (the law governing the Reclamation
Board and reclamation districts) and whether to create a reclamation
district. The structure, officers, and operation of reclamation districts
are set out in the various sections of Chapter 252 of the General Laws.
146
-------
Mosquito abatement may be undertaken in any manner approved by
the Reclamation Board by the Board of Health of a city or town not in-
cluded in an improvement program area under the Reclamation Board or by
the commissioners of a mosquito control project established under the
Board. Prior to undertaking such abatement procedures, the owners of the
area where the procedures will be undertaken must be notified in the news-
paper published in the town where the area is situated. The notice must
indicate the time and place of a public hearing on the abatement program.
At the hearing, the Board of Health or the commissioners must hear all
interested parties.
An owner of any part of the area where the abatement program
will be undertaken can appeal the decision to carry out the program to the
county commissioners within 14 days after the hearing conducted by the
Board of Health or the commissioners. The commissioners shall hear the
petitioner(s), the Board of Health or commissioners, and the Reclamation
Board or its agent within 14 days after receipt of the appeal. If the
county commissioners do not decide within two weeks that the abatement is
not required, then it may proceed. Any person who suffers property damage
by any work undertaken for mosquito abatement purposes may recover his
damages according to law from either the city or town undertaking the
project or from the county or counties in which any city or town included
in the project is located when such work is undertaken by commissioners
appointed by the board.
(2) Development of Vector Control Programs. The State of
Massachusetts has eight mosquito abatement districts, six of which are set
up under separate legislative acts—the other two come under Chapter 252
147
-------
of the General Laws. The history of vector control in Massachusetts can
be traced back to 1870 or 1880 when the town of Belmont did the first
mosquito program to control malaria before the malaria cycle was actually
worked out. The next step was taken in Cape Cod where local people
financed a number of private and municipal attempts around 1920 to control
mosquitoes, including the spraying of oil over standing water on the marsh
lands.
In 1928 the Cape Cod Chamber of Commerce organized a countrywide
fund-raising drive to raise funds for mosquito control. In these years,
it was very obvious that the prevalence of mosquitoes on Cape Cod could
prevent the area from becoming one of the leading recreational areas in
the East. The fund-raising committee obtained $200,000 and helped estab-
lish the Cape Cod Mosquito Control Project.
In 1929, in an amendment to the Chapter 252 through Chapter 288,
mosquito control is mentioned for the first time in the laws of
Massachusetts. Under this chapter, authority is given to towns and cities
for the improvement of lowlands and swamps and the eradication of mos-
quitoes. In 1930, legislation was enacted creating the Cape Cod Mosquito
Control Project by Chapter 379. Upon enactment of this legislation, the
first mosquito control project in the state came under the direction of
the State Reclamation Board within the Department of Agriculture.
During the middle and early thirties, considerable ditching
throughout the coastal area of the state was performed by the Works
Progress Administration (WPA) which made personnel available for marsh
work. Afterwards, the individual cities and towns financed the maintenance
of such works through the State Reclamation Board.
148
-------
The second mosquito control project was created by Chapter 456
of the Acts of 1945 in Berkshire County. This is the only district not
in the eastern part of the state.
In 1956 the Norfolk Mosquito Control district was created by
Chapter 341. The creation of a number of other districts immediately
followed. In the same year the Bristol County District was created by
Chapter 506, the Duke County by Chapter 371 (although this project never
materialized because four out of the six towns included in the district
withdrew shortly after they were entitled to organize). Plymouth County
was organized in 1957 and Essex County in 1958. The Essex project did not
begin operating until 1964 because sufficient funds were not made available.
There are also two other mosquito control projects in the State
of Massachusetts, the voluntary projects of East Middlesex and South Shore.
a
Although not created by legislative acts, they have been in effect for some
time under the general supervision of the Reclamation Board.
In 1948 a law was enacted establishing greenhead fly control
projects. Work was performed under the direction of the Executive Secretary
of the State Reclamation Board. Essex County and Cape Cod formed control
districts while the South Shore performed the works as a voluntary project.
For those towns and cities that have set up as a reclamation district, the
state government pays one-third of the total cost of greenhead fly control
and the remaining two-thirds is financed by the individual cities and towns.
If a district is not established the communities bear the entire cost of
the program.
The Cape Cod Greenhead Fly Control District was administered
under the Mosquito Abatement Project, and the Essex County District and
South Shore project were also turned over to the Mosquito Abatement districts
after their creation.
149
-------
The mosquito and greenhead fly control projects are all under
the direction of the State Reclamation Board. The Board appoints the
district commissioners who are in charge of managing the vector control
project. The commissioners hire a superintendent and all other necessary
personnel for the proper conduct of the project.
The projects are financed by the individual towns who are mem-
bers of the district. The appropriations, which are established under
the legislative acts for each district, are based on the assessed value of
the town or area real estate as established by the State Treasurer. In the
voluntary projects of South Shore and Middlesex, the appropriation is made
annually at a town meeting and is subject to variation from year to year.
The district funds are deposited with the State Treasury Office and as the
districts incur expenses they send the bills to the Reclamation Board for
approval. The Board in turn sends it for payment to the comptroller's
office.
In addition to abatement districts, individual towns take upon
themselves from time to time mosquito control projects which sometimes
overlap with district abatement programs.
c. Massachusetts Clean Waters Act—Chapter 21 (1966)
The Division of Water Pollution Control has the following
responsibilities under the law:
(1) To encourage the adoption and execution by cities,
towns, industries, and other users of waters in the
Commonwealth and by cooperative groups of municipali-
ties and industries, of plans for the prevention, con-
trol, and abatement of water pollution.
150
-------
(2) To cooperate with appropriate federal agencies or
agencies in other states and with interstate agencies
in matters related to water control quality. The
division shall also cooperate with and assist depart-
ments, boards, officials, and institutions of the
Commonwealth or its political subdivisions that are
concerned in any way with the problems of water
pollution.
(3) To conduct a program of study, research, and demon-
stration by itself or in cooperation with other
governmental agencies relating to new and improved
methods of pollution abatement and more efficient
methods of water quality control.
(4) To adopt standards of water quality applicable to
various waters or portions of waters in the Commonwealth
and a plan for implementation and enforcement of those
standards. Standards that relate to the public health
shall be adopted only with the written approval of the
Commissioner of Public Health.
(5) To examine periodically the water quality of various
coastal waters, rivers, streams, lakes and ponds in the
Commonwealth and to publish the results of such exami-
nations together with the standards of water quality
established for said waters.
151
-------
(6) To prepare and keep current a comprehensive plan which
shall be approved by the Water Resources Commission
for the abatement of existing pollution and the preven-
tion of further pollution of the waters of the
Commonwealth.
(7) To arrange for personnel engaged in water pollution
prevention and abatement to take courses designed to
instruct them in methods of water pollution control.
(8) Adopt, amend, or repeal after hearing and with the
approval of the Water Resources Commission, rules and
regulations necessary to properly administrate the
laws relative to water pollution control and for the
protection of the quality of water resources.
(9) To require submission for approval of reports and plans
for abatement facilities and to inspect such facilities
to assure their compliance with the approved plans.
(10) Undertake immediately whenever there is spillage,
seepage, or other discharge of oil into any of the
waters of the Commonwealth or any offshore waters which
may result in damage to the water shores or natural
resources of the Commonwealth, to contain or remove
such oil.
The division is authorized under the law with the approval of
the Water Resources Commission to propose water pollution abatement dis-
tricts consisting of more than one city or town for the purposes set forth
in the law. The division is to supervise the operations and maintenance
152
-------
of any facilities of the pollution abatement district and the director may
require the district commission to take such immediate action as may be
necessary to maintain the required standards.
The Director of the Division of Water Pollution Control is to
provide for the conduct of research and for demonstration projects related
to water pollution control.
The director or his authorized representative may at reasonable
times enter upon any public or private property to investigate or inspect
any condition related to the pollution or possible pollution of any waters
and may make such tests as are necessary to determine the source of pol-
lution. The director or his authorized representative may also examine any
records or papers pertaining to the operation of any disposal system or
treatment works.
The law provides for a fine of not more than $1000 for anyone
who directly or indirectly throws, drains, runs, or discharges into the
waters of the Commonwealth organic or inorganic matter which causes or
contributes to conditions in contravention of the water quality standards
adopted by the division. Each day the violation continues is a separate
offense and punishable by a similar fine. The director is to notify the
person making or permitting such discharge in writing and order the person
to correct the condition or complaint according to a schedule included in
the letter. Such an order is to inform the alleged violator of his right
to request a hearing within 30 days. If a hearing is not requested, the
person is deemed to have consented to the order. If the person requests
a hearing, the director is to hold a hearing according to the provisions
in the law. The director may then reissue such orders as are warranted.
153
-------
All orders, permits or other determinations of the director ex-
cept those consented to are subject to judicial review. The Superior Court
of the Commonwealth has jurisdiction in equity to enforce any such order,
permit, determination, rule, or regulation issued under the law. The
Superior Court, if the public health, safety, and interest require it, may
enjoin any pollution prior to the final determination of any proceeding.
The Members of the Water Resources Commission individually and
the Commissioner of the Department of Public Safety compose a board for
the purpose of insuring that certain chemical and hazardous wastes are
safely and properly handled and disposed of. The board is authorized to
investigate the handling and disposal of such wastes and to coordinate the
activity of agencies represented by the members of the board. The board
can adopt rules and regulations to protect the public and its environment
from the effects of unregulated handling and disposal of these wastes.
The board delegates the responsibility for the administration of its rules
and regulations to the most appropriate agency as represented by a member
of the board.
After public hearing, the board can adopt rules and regulations:
(1) Identifying substances which constitute or may reasonably
be expected to constitute a danger to the public health,
safety, or welfare or to the environment and which
should be handled and disposed of by licensed waste
disposers.
(2) Specifying in what manner wastes may be handled or dis-
posed of.
154
-------
(3) Specifying the location in which such substances may
be disposed of within or without the Commonwealth to
prevent damage to any resource or to the environment.
(A) Establishing reasonable exceptions when scientific
evidence satisfies the board that certain substances
and quantities involved do not constitute a threat to
the public and its environment.
(5) Establishing reasonable license and inspection fees.
(6) Establishing such other rules and regulations as
necessary to assure that hazardous wastes are being
properly handled and disposed of and to assure that
such hazardous wastes are handled by licensees of the
board.
Licenses are to be issued by the board to persons to handle
and dispose of hazardous wastes. The terms and conditions of the license
will be those set out by the board in accordance with its rules and
regulations.
A violation of the laws with respect to the safety and proper
handling and disposal of hazardous wastes and the licensing of persons to
handle and dispose of such wastes are punishable by a fine of not more
than $5000 and by imprisonment in jail or the house of correction by not
more than six months, or both. The Superior Court has jurisdiction in
equity to enforce the provisions of the law.
Any general or special law reference as to the authority to
administer water pollution abatement or control laws in the Clean Waters
155
-------
Act is intended to be referred to the Division of Water and Pollution Con-
trol. Laboratory services of the Department of Public Health are made
available under the law to the Division of Water Pollution Control at cost.
3. Relevant Incidents
a. Methods of Investigating Complaints
There is little active effort by the Pesticide Board to control
the sale, use and application of pesticides in the Commonwealth. Rather,
it depends upon receiving complaints about those who are using or apply-
ing pesticides from citizens, government employees, and others. Unless
such complaints are made, the board seldom investigates or makes other
attempts to control pesticides under existing laws and regulations.
There have been numerous complaints and incidents regarding
pesticides presented to and investigated by the Massachusetts Pesticide
Board since the board was established. Complaints are made known to the
board in a number of ways, but usually through phone calls, letters, or
personal meetings with the executive officer of the board. The complaints
handled by the board cover a broad range including accidental spilling of
pesticides, fish kills, bird kills, and hazards such as airplanes flying
over populated areas after or during pesticide spraying.
Complaints are all handled in a similar fashion. The executive
officer of the board, as time and resources permit, attempts to investi-
gate each complaint and to determine whether it is justified, the basis
for that justification, and whether the Pesticide Board or another state
agency should take any action with respect to the complaint. When com-
plaints are considered by the personnel of the board, the investigation
is thorough. In most cases all people who have had anything to do with
the incident are interviewed and a summary of the interview information
is retained.
156
-------
Much time, knowledge, and skill is required of the investigator.
He must be aware of technical pesticide used, their names, their proper
application; he must be aware of alternative expalnations for the result
which is being complained about; he must know which people and agencies
to see about the problem; he must be aware of other aspects of the problem
such as medical, social, legal, and environmental.
The investigator must interview people at length to find out
what really happened or what was observed. He must be able to document the
results through sampling and testing, through photography, and through
witnesses. He visits the site of the incident and attempts to explore all
possible explanations at the site with witnesses or complainants and with
others who may be able to contribute alternative theories and support for
them. The investigator spends a great deal of time in carrying out these
elements of the investigation and must travel a great deal to do so.
The Massachusetts Pesticide Board has one employee charged with
investigating incidents of pesticide misuse or harm caused to human beings
or environment by pesticides. The same person is also responsible for
administering all the rules and regulations of the board and for carrying
out the law regarding pesticides when that responsibility falls to the
board. This person must also handle all correspondence, much planning and
policy, executive actions, record-keeping, and most of the social and
political difficulties that arise from pesticide use and application.
Consequently, because the Pesticide Board executive officer is so busy,
the complainant often must request action by the board more than once if
his complaint is to be followed up. The result is that too much of the
burden of protecting against harm to human beings or the environment caused
157
-------
by pesticides is thrown upon citizens who might observe an incident which
deserves the attention of the board. Moreover, the complainant must be
skillful enough to locate the Pesticide Board within the state government
to even deliver the complaint.
b. Synopses of Specific Incidents
(1) Mosquito fogging by golf course. The board received a
request from the local board of health for assistance in dealing with
citizen complaints about mosquito fogging operations carried on by a golf
course. The executive officer of the board visited the operator of the
course, accompanied by the director of the county mosquito control project
in whose district the golf course was located.
The method of spray was a swing fogging device with a generator
used to fog a mixture of 6% DDT, 2% chlordane, and 2% thanite in a
petroleum distillate carrier. Spraying was done at about 8:00 p.m. on
nights when mosquitoes were intense. The executive officer instructed the
operator to use another more appropriate spray and to fog only when the
fog would not cross the road to reach nearby homes.
The executive officer visited the complainant who showed him
plants in their front yard that they claimed were damaged by the spray.
Also, one complainant had been under treatment for a respiratory ailment
which he indicated was aggravated by the spraying. They further complained
that the kerosene smell got into their clothes and house and that the road
was literally blocked because the fog was so thick.
The executive officer visited the Chief of Police in the town
who reported the road was not blocked by fog at the time the cruiser
arrived.
158
-------
As a result of his investigations, the executive officer con-
cluded that there was some justification for the complaints, but that the
course did require a mosquito control program. He set out an improved
program in detail which, in his judgment, would reduce the problem of
drift and which took advantage of better mosquito control spray materials.
(2) Aerial spray to control mosquitoes in three towns. A series
of complaints about dead and dying small birds was found throughout three
towns which had just previously undertaken a helicopter spray program to
control mosquitoes using Baytex at a rate of one ounce of 93% ULV per acre
mixed with a petroleum solvent.
Fish and Game, Audubon Society, and Chemagro (the manufacturer of
Baytex) personnel collected samples of the birds for laboratory analysis.
The executive officer of the board received letters and phone calls indi-
cating citizen outrage or concern, with estimates of the bird kill including
"thousands" and "10% of the bird population." He determined that the
Baytex was used properly and that it was loaded under the supervision of
the superintendent of the area mosquito control district.
The results of some laboratory tests were presented to town
meetings by the Audubon Society as not indicating that the spray program
caused the bird kill. However, many citizens and public officials remained
skeptical and scientific evidence was at best inconclusive. No results
were ever made available from Chemagro's laboratory work.
(3) Aerial spray to control mosquitoes.' A complaint was
received by the board of slight fish kill in swampy areas and two specific
ponds. A helicopter spray program was reportedly being carried out in
the area using Baytex at a rate of 1/2 gallon per 60 gallons of water
(about one fluid ounce per acre).
159
-------
The board executive officer contacted the helicopter company
who reported the use of Abate, not Baytex, at the same rate. Company
personnel also indicated that the area being sprayed was heavily polluted
from industrial, town dump, and other sources.
Investigation at the site did not result in observing any dead
fish. Heavy pollution from other sources, however, was apparent. The
executive officer concluded that any slight fish kill which existed was
likely the result of this other pollution and reported this, with a summary
of his field notes, in a letter to the complainant.
(A) Greenhead fly spraying program. A complaint was received
by the board that the Cape Cod Mosquito Control District spray program for
greenhead flies v/as causing plankton and clam kill in a nearby fisheries
research facility.
Greenhead fly treatments of malathion in oil applied as a fog
and ULV malathion were used in the general area on two occasions and
plankton pools at the research facility stopped producing immediately after
both treatments. When drained, cleaned, and refilled at high tide, the
pools began producing again. Quahog clam kills in laboratory trays were
also complained about.
The board executive officer visited the research facility, col-
lected samples of water, mud, clams, and plankton and took them to the
nearby Cranberry Experiment Station to be analyzed for chlorinated hydro-
carbons. He also thoroughly checked out any pesticide use by the town and
cranberry growers in the area and found that almost none had been used.
160
-------
The laboratory results were inconclusive. The executive officer
suggested a program of wider monitoring and additional testing, and the
fisheries research facility agreed to contact appropriate laboratories who
might be equipped to carry out such work.
(5) Mosquito larviciding program. The board received a complaint
from a town conservation committee about a large fish kill in several local
ponds. Several people had reported the incident to other local and state
government agencies.
The executive officer of the board visited the sites and found
many dead fish and some dead eels and arranged to have samples taken and
analyzed. He discovered that a mosquito larviciding treatment had been
made in the upland areas around the ponds in the morning using Baytex at
one fluid ounce per acre in one quart of kerosene. In the afternoon,
people swam in the pond, noting both fish kill and algae bloom. Two days
later other persons noted fish kill. It rained that day, and diazinon
was applied to cranberry bogs upstream from the ponds on that day. The
next day another complainant noted fish kill and algae bloom.
The executive officer discovered a history of problems with these
ponds, including past fish kills, silting, and so on. He concluded that
the fish kill he was investigating could have been caused by oxygen
deficiency, mosquito spraying, cranberry spraying, or a combination of all
three.
(6) Aerial spray to control mosquitoes. The board received a
complaint from a bee keeper that he had lost three hives due to aerial
spraying to control mosquitoes in the swampland where the bees were located.
The county bee keeper association also registered a ccrenplaint because of
161
-------
the incident and asked to be notified prior to any spraying so that they
could protect their hives.
The executive officer visited the complainant who had lost the
bees and explained the existing rules and regulations regarding aerial
spraying. Basically, these regulations require local law enforcement
officers to be notified prior to spraying.
At a subsequent air sprayer meeting, the incident was discus-
sed, the regulations of the Massachusetts Aeronautical Commission and the
Federal Aviation Administration were discussed, and there was a concensus
that all areas should be surveyed for beehives prior to spraying.
(7) Pesticide spillage at a public beach. The board received
a complaint that a pesticide spray truck taking on water for spraying
purposes at a public boat landing and beach area had discharged a large
amount of milky liquid into the water. The complainant had called the
local police.
The executive officer visited the local police chief about the
incident and observed the site. No fish kill or other indications of the
spill were 'evident, but other people had reported foam at the waters edge
from the incident. He visited with the complainant who had observed the
incident and reported it to the police. The complainant had observed a
spill causing a milky liquid area in shallow water about 20 feet in
diameter. The operator of the truck told.the complainant that such dis-
charges often occurred but that the mixture in the water was harmless
because there was no pesticide in it. The owner of the truck indicated
the mixture discharged was only spreader-sticker because 'the zineb-carbaryl
pesticide had not yet been put into the tank.
162
-------
The executive officer concluded that no apparent harm had resul-
ted from the discharge, but he was very concerned about the site chosen
to take on water and the careless manner in which the water loading was
done. A letter was sent to the owner of the truck indicating that if any
further violations of the rules or regulations occurred, appropriate action
would be taken.
(8) Discharge of pesticide into a stream. A licensed appli-
cator reported to the board that excess 2,4,D-urea 45 mixture had been
dumped by mistake into a stream by a crew for which he was responsible.
No attempt by the board was made to investigate the results of this dump-
ing. However, a hearing was held to consider the incident by the board.
The applicator explained that the crew had violated his in-
structions, dumping the excess pesticide into the stream where they usually
took on water instead of into a gravel pit as instructed. He argued that
the incident was not a reflection on his competence, but a case of a sub-
ordinate not following instructions.
The board, in executive session, decided to send a letter to
the applicator and did so, stating that disposal of pesticides was an
important aspect of the proper use of pesticides and that further violations
of the rules and regulations of the board could lead to the loss of the
applicator's license.
(9) Application of pesticides without Massachusetts license.
An applicator licensed in Connecticut applied to the board to be licensed
in Massachusetts. His application was denied, but no reason for the denial
was given. The applicator asked for a hearing before the board, the
request was granted and the hearing date set, but was postponed because
the applicator's attorney could not be available.
163
-------
A complaint was then received by the board from a Massachusetts
citizen that the spraying of a crop by this same applicator in Massachusetts
had damaged cucumbers not located in the spray target area.
The next day the executive officer of the board investigated the
applicator in Connecticut and found him to be licensed there. On that same
day the complainant made another complaint to the board regarding a second
spraying by the same applicator. This time, the complainant called the
state police. The applicator told the police he was working under the
license of a Massachusetts firm which had licensed personnel.
Three days later, an officer of the applicator's firm in
Connecticut called the executive officer and stated that the applicator
had made an honest mistake because the Massachusetts firm had told him
that he was working under their license. However, the Massachusetts firm
denied they had ever implied that the applicator could work under their
license. On the same day, the applicator sprayed again in Massachusetts
and the complainant called a local constable to have the spraying stopped.
Two days later, the board was informed that the same applicator
had been hired to spray the Suffolk Downs Racetrack property. The
executive officer indicated that he was not licensed and thus could not
carry out the program. As a result, the management of Suffolk Downs ob-
tained another contractor to do the spraying.
After discussion with the Chairman of the Board, the case was
referred to legal counsel for the Department of Public Health for prese-
cution. Subsequently, the applicator again made formal application for a
Massachusetts license. Apparently, no action has ever been taken on
either matter.
164
-------
(10) Aerial spraying of potatoes and disposal of pesticide
containers. Several citizens complained to the board by
letter and phone about drifting spray materials and the nuisance of a low-
flying airplane being used to spray potato fields near their homes.
The executive officer visited the site and noted herbicidal
effects at the field edges and well onto property of adjacent landowners.
He found the pesticide storage area used by the potato grower unlocked. Many
pesticide containers were on the ground, including three parathion bottles
with significant amounts of concentrated parathion remaining in each one.
Water in a nearby ditch leading to other streams and ponds was a deep
yellow color, having been contaminated with dinitrophenol, a potato-top
killer.
The executive officer write a strong letter to the potato grower
regarding these findings and requested a meeting to discuss them personally.
(11) Fire in a pesticide storage area. A barn at a country
club in which pesticides were stored burned, and water hosed over the burn-
ing building ran into a nearby private pond killing all or nearly all the
fish in the pond. A series of wells serving as a public water supply was
located about 3/4ths of a mile downstream from the pond.
The executive officer helped arrange for a laboratory analysis
of the water which showed that the pesticides in the barn were amanate,
thiram, actidione, and one other that could not be named by the laboratory.
(12) Truck accident causing pesticide spillage. The board
received a report of a pesticide spill as a result of a truck accident.
The executive officer contacted the witness and found the accident had
occurred at 8:30 p.m., causing one drum to break open. He then contacted
the trucking company. The company said the accident involved one drum of
165
-------
parathion, 98%, for manufacturing use. The drum fell from the truck onto
its top and came to rest leaking. Only one pound of material was lost as
determined by weighing the drum. The spill on the pavement was wet down
with a bleach solution, adsorbed into chlorinated lime, and swept up. The
spill on the highway median was covered with chlorinated lime. The truck
was not contaminated.
The executive officer visited the site of the accident and
found no odor nor any remaining evidence of parathion. The area was still
liberally sprinkled with lime at the time of his visit.
(13) Cranberry spray program. Fish kill in two ponds was re-
ported by town officials to the Division of Fish and Game. Investigation
by the division indicated that DDT and Guthion had been used in cranberry
bogs on tributaries of the ponds and that accelerated runoff had resulted
from substantial rainfall at the time of the fish kill.
j
The next day and on subsequent days, water and fish samples were
taken for analysis. About 500-600 pounds of dead fish were observed
(bluegills, brown bullheads, yellow perch, white perch), and fish were ob-
served in shallow areas exhibiting nervous spasms. They could easily be
caught by hand. The duration of the kill was about two days.
Laboratory analysis showed negative results at 1 ppb sensitivity
for chlorinated hydrocarbons including DDT in water samples. However,
Guthion, an organophosphate showed concentrations of as high as 12.57 ppb
in water samples. The 96-hour TL, of Guthion for bluegill is 5.2 ppb,
and two of four samples from one pond and two of three samples from the
other showed concentrations higher than these. Consequently, the Division
of Fisheries and Game concluded that Guthion caused the fish kills in both
ponds.
166
-------
C. OTHER NEW ENGLAND STATE'S REGULATION OF PESTICIDES
1. ORGANIZATIONS
a. Connecticut
Connecticut has a State Board of Pesticide Control with the
following members:
Voting
Commissioner of Agriculture and Natural Resources
Cor tnissioner of Health
Director of the Connecticut Agricultural Experiment Station
Non-voting
Chairman of the State Board of Fisheries and Game
Chairman of the State Park and Forest Commissions
Chairman of the Water Resources Commission
Chairman of the Shellfish Commission
Highway Commissioner
Three members appointed by the governor
One of the members is appointed by the governor as chairman of the board.
b. Maine
Maine has established a Board of Pesticides Control with the
following members:
Commissioner of Agriculture
Commissioner of Health and Welfare
Commissioner of Forests
Commissioner of Inland Fisheries and Game
Commissioner of Seas and Shore Fisheries
Chairman of the Public Utility Commission
167
-------
Highways Commissioner
Water Improvement Commissioner
The board elects a chairman from its own membership each year.
Commissioners of the state departments may appoint agents to serve in
their absence.
c. New Hampshire
New Hampshire has established a Pesticide Control Board with the
following members:
Commissioner of Agriculture
Director of the Division of Public Health Services
Director of the Division of Resources Development
Director of the Fish and Game Department
State Entomologist
Executive Director of the Water Pollution Commission
Four (A) members appointed by the Governor.
The Governor makes his appointments as follows: one member from
the general public, one member from the slate of three persons presented by
the New Hampshire Horticultural Society, one member from a slate of three
persons presented by the Hew Hampshire Arborists Association, and one member
who is a recognized ecologist, preferably holding a doctorate in ecology.
The board selects its own chairman. However, the Executive Director
of the Water Pollution Commission is the Executive Secretary of the board
and coordinates the information and data developed by the Water Pollution
Commission and the Department of Agriculture under the statute.
d. Rhode Island
Rhode Island established a Technical Pesticide Advisory Board
with seven members:
168
-------
The Director of Natural Resources (ex-officio and chairman)
The Director of Health (ex-officio)
Two members representing the public and appointed by the Governor
Two members representing the disciplines of ecology and acquatic
biology appointed by the Chairman of the Board of Regents
One member from the Agricultural Experiment Station appointed
by the administrative head of the station
The board is responsible for advising the Director of Natural
Resources concerning policies, plans and goals to be attained in administering
pesticides control legislation, and to make recommendations to the Director
at least annually. The board is also to review, comment and present recom-
mendations on all regulations proposed by the Department of Natural Resources
before public hearings are held on such regulations or before they go into
effect, whichever is earlier.
e. Vermont
Vermont has established a Pesticides Advisory Council, the
membership of which is constituted by representatives with knowledge of
pesticides from the following:
Fish and Game Department
Department of Water Resources
Department of Agriculture
Department of Forests and Parks
Department of Health
Aeronautics Board
Physician from College of Medicine, University of Vermont
Person engaged in Pesticide Research from Vermont Agricultural
Experiment Station
Person engaged in entomology from Vermont Agricultural
Experiment Station
169
-------
The Chairman of the Council is designated by the Governor, serves as his
personal representative, and coordinates the activities of the council.
2. LAWS, REGULATIONS, AND REGULATORY PROCESSES
As indicated in the section above, all northeast states (Con-
necticut, ;i,-n a •„• :.',,,apshire , Rhode Island, Vermont) including Massachusetts
have some type 01 pesticide control board. The purpose of the pesticide
control boards is similar in all states. Basically, it is to safeguard
<•
the public health, welfare, and environment from harmful effects caused by
hazardous pesticides.
The substance of the legislation establishing these pesticide
control boards is also similar. Included are the registration of licensing
of commercial applicators and of other personnel who deal with pesticides.
In most states the board can require an examination before a person is
licensed as a pesticide applicator. Such licenses may have restrictions
or may be limited to certain uses. The licenses may be suspended by the
boards either before or after hearing and the boards are all authorized to
revoke or modify the licenses if the licensee has violated the rules,
regulations, or laws governing pesticides or for other reasons. Recip-
rocity is given by all states to other states who have similar licensing
procedures and vivo also grant reciprocity. Exemptions from the licensing
procedure usually include experimental uses of pesticides by universities
and other scientific personnel and property owners when applying pesticides
in or immediate around buildings which they own. Exemptions are sometimes
given for bona fide farmers and arborists. Arborists in most states,
however, are licensed to care for trees, shrubs, and other similar plants
under a separate statute, often with separate rules and regulations. In
170
-------
most states the arborist is required to have a license from the Pesticide
Control Board before he can apply pesticides in the course of his work.
Many states require a proof of financial responsibility from
commercial applicators in the form of a certain amount of liability insurance,
In all states members or personnel of the board may inspect
equipment and techniques used to apply pesticides and are permitted to
go onto property at reasonable times to do so. In some states they may
require repairs before equipment can be used for pesticide applications.
In nearly all states the board requires records to be kept by
commercial and other applicators and to be made available to the board upon
request. In some states, such as New Hampshire, such records are mandatory
under the law and not discretionary with the board. In fact, the New
Hampshire law requires the board to keep the list of licensed applicators,
permit holders, and of the quantities of pesticides used in the state.
All states require that one licensed member must be with each
applicator crew during spraying.
All pesticides boards are authorized to adopt regulations, and
rules as necessary in order to control the sale, use and application of
pesticides.
The enforcement of the law and the rules and regulations of
the pesticides boards varies from state to state. In New Hampshire the
board is authorized to enforce its rules and regulations and the law which
created and gave the board its powers. In other states, such as Maine,
the personnel of the state agencies represented on the pesticide control
board are authorized to enforce the laws, rules and regulations of the board
as seen to be most appropriate by the members of the board.
171
-------
Most boards can suspend the regulations in order to better or
more effectively combat an emergency.
The law in some states provides a mechanism for persons ag-
grieved by any board action to appeal the action. In Maine, a person
may appeal a board action directly to the courts.
The penalties for violation of the laws, rules, and regulations
governing pesticide sale, transportation, use, and application of pesticides
vary from $100 per violation for the first violation, to $500 for such
first violation but do not go higher that $500 for each violation except in
the case of aerial applications of pesticides for which, in some states,
the fine is as high as $1,000 per violation.
The responsibilities of the pesticide boards vary from state
to state. In the case of Vermont, there is a pesticide advisory council
whose responsibilities include advising the executive branch on legislation
and suggesting programs, policies, and legislations to the executive branch.
In addition, the council prepares a summary of hazardous pesticides needing
control. It also reviews control programs using pesticides for safety and
efficiency and serves as an advisory board to the aeronautics board on
aerial applications of pesticides. These duties are more general and more
policy oriented than are the duties of most other boards. Usually, the
boards regulate the sale, transportation, use, and application of pesticides
through means of registration, labeling, and licensing, by promulgating
rules and regulations, and by making provisions for enforcing these regulations,
In Maine, for example, the board regulates all applications of pesticides
and charged by law with designating critical pesticide use situations, limit-
ations on the use of pesticides, and spelling out what constitutes unsafe
172
-------
practices in using and applying pesticides.
In the Vermont statute the Commissioner of Agriculture is
charged with the responsibility of regulating the sale and use of pesticides,
He only acts upon the advice of the pesticide advisory council and with the
approval of the Governor. The powers spelled out in the act are the powers
of the Commissioner and not of the board. However, powers are very similar
to those given to pesticide boards in other states.
The regulations promulgated by the pesticide boards in the
northeastern states are similar in many respects. Applicators under most
regulations are charged with cooperating with the board and its personnel
who are investigating, sampling, and otherwise observing pesticide applica-
tion techniques used by applicators.
Safety is handled under most board regulations by a statement
indicating that the licensee will instruct himself and all personnel as to
the dangers and problems of pesticide use and will supply the safety equip-
ment required to safeguard personnel against hazards from the use of
application of pesticides.
Reports of pesticide use are only required in states of Maine
and New Hampshire. In other states such reports can be requested by the
board but they are not required as a part of the normal course of events
in utilizing or applying pesticides.
Most regulations indicate that the use of any pesticide not
registered by the state and sometimes also by the Environmental Protection
Agency or the U.S. Department of Agriculture are prohibited in the state.
A significant number of circumstances is set out in board regula-
tions in the northeast states requiring the approval of the boards before
173
-------
specific pesticides can be used in certain ways or applied in certain areas
within the states.
In Maine, for example, there is no pesticide application allowed
on or in any water or water supplies within the state without approval
of the board. Application for such approval must be made in writing with
ample detail for the board to justify a decision to allow such pesticide
applications to proceed. There can be no machine applications, overflow,
spilling, or washing from any machine used to apply pesticides into any
water supply in the state without approval by the board.
The disposal of empty containers and surplus pesticides is not
covered by rules and regulations in all northeast states. In Maine a recent
revision of the pesticide control regulations indicates that empty containers
should be returned to the manufacturer or to a reconditioning company and
that empty containers which cannot be returned or reconditioned should be
stored in a safe place or buried or returned to the manufacturer.
In Vermont, pesticide drift is to be minimized, and pesticide
operators should buy marerials and conduct operations under conditions
known to minimize the contamination of other than target land and target
organisms. A statement on standard operating procedures is also included,
indicating in a general way that all persons engaged in the business of
pesticide uses should use only methods and equipment which insure proper
application of the materials, should operate in a careful manner, and only
when pest and crop conditions are proper for controlling pests in the locality.
Only in Vermont is the protection of bees and other pollinators
specifically provided for in the regulations.
174
-------
In New Hampshire, board regulations state that no pesticide can
be applied on water, public watershed areas, or on marsh land for mosquito
control without board approval. No surface water application for any reason
is allowed without board approval in New Hampshire, nor is any application
by plane.
D. DEGREE OF ENVIRONMENTAL PROTECTION PROVIDED BY EXISTING LAWS, REGULATION'S.
AND PROCEDURES
1. Introduction
The existing laws and regulations governing the sale and use of
pesticides in the study area are generally adequate. They provide broad powers
for establishing regulations and authority to monitor and otherwise control
activities dealing with pesticides. However, the powers created by law are
not excercised because of lack of money, facilities, and personnel. The
result is that the requirements of the law are not well known by those who
use pesticides, there is virtually no knowledge of how well the sale and
use of pesticides conforms to the laws and regulations, there is little done
to monitor or control pesticide activities under the laws and regulations,
and little effort is devoted to monitoring developments in the pesticides
field and to the integration of these developments into state programs
and practices. Consequently, the degree of environmental protection that
could be provided by existing laws and regulations is not attained because
an insufficient level of effort is devloted to assuring that procedures
and practices conform to these laws and regulations. The Massachusetts
Pesticide Reclamation Boards each have one executive person to carry out
monitoring, investigation, and other control activities, correspondence,
and other actions under the laws governing pesticides. The executive officer
175
-------
working for the Pesticide Board is the official source of pesticide control
information in the state and must maintain all records, files, and carry
out nearly all other administrative duties of the Pesticide Board. He has
no lavoratory facilities, technicians, or other skilled personnel to assist
him. The person working for the Reclamation Board is in a similar situation.
In addition, he faces directors in the mosquito control districts who are
used to operating without supervision or control. As a result, the public
interest in the sale, transportation, use, application, or effects of pesticides
is not adequately protected.
There are two basic approaches that could be used to solve this
problem. First, the law governing pesticides could be made very specific
so as to require certain activities on the part of the executive agencies of
state and local government. Second, the present broad and flexible legal
authority could be utilized better by more adequately financing and staffing
the executive arms charges with responsibility for pesticide and vector control.
The second option would be preferable because it can meet public
and individual needs more precisely and speedily. It is not clear what exact
confluence of events is necessary to attain it. However, it will likely
require a clear presentation of the needs for additional funds, the request
of such funds as a part of the executive budget request, a sympathetic
legislature, and perhaps a higher degree of public awareness and reaction to
the pesticides control issue so as to alter its priority among other public
interests requiring funds.
2. Regulation of Sales
The sale of pesticides at the wholesale and retail levels in Mass-
achusetts is virtually unregulated. Massachusetts legislation provides that
176
-------
no wholesaler or distributor other than a person selling at retail can sell,
offer to sell, distribute, or deliver a pesticide within the Commonwealth
unless he has a license to do so from the Department of Public Health.
In addition, the licensee shall, at the request of the pesticide
board but not more often than once a year, supply the board with information
concerning the quantities of pesticide sold which are being regulated by
the board or which are being considered for regulation by the board, including
the names and addresses of purchasers or recipients. The Department is
charged under the law with issuing a license once it has determined that rules
and regulations promulgated under its authority to regulate sales have been met.
However, these regulations have not yet been drafted, and no licenses are being
issued.
Thus, in practice no attempt is made in the Commonwealth to control
sales, to monitor them, or to determine the nature of the problems at the whole-
sale and retail sales levels. Little information is made available to retailers
about the kind of sales that can be made and about details of handling special
permit sales, experimental use sales, and other similar sales. No records are
required of the retail sale of pesticides under the law.
Certain acts are, however, unlawful. These include to distribute,
sell, or offer for sale in the Commonwealth or to deliver for transportation
or transport in interstate commerence or between points within the Commonwealth
throughout any point outside the Commonwealth any of the following:
1. Pesticides not registered or not the same when sold as when
registered.
2. Pesticides, unless they are in the registrant's or manufacturer's
immediate container and properly labeled.
3. Pesticides highly toxic to man and not properly labeled.
177
-------
4. Pesticides not discolored which are required to be discolored.
5. Pesticides which are adulterated or disbranded, or any device
which is misbranded.
However, only a few of these acts come to the attention of the Department or
the Board unless reported by a citizen or member of another governmental agency.
3. Regulations of Uses and Application Techniques
By regulation, the Massachusetts Pesticide Board has prohibited
the use of DDD (TDE), aldrine, endrine, heptachlor, and marine anti-fouling
paints which contains mercury in any form or compound.
In addition the board has restricted the use and applications of
dieldrin, chlordane, BHC, 2, 4, 5-T and its esters and salts, DDT, and toxa-
phene. Activities dealing with marine anti-fouling paint containing mercury
which is already applied are restricted also.
The regulations of the board state that no person shall apply or
use a limited or prohibited pesticide except in accordance with the permit
issued by the board and subject to such restrictions as are imposed by the
board in the permit. All such permits are revocable and may be revoked with-
out a hearing by the board at any time.
The permit or proof that such a permit is held by a person must be
exhibited or furnished when purchasing such prohibited or restricted pesticides.
No one can sell or distribute any pesticide listed as a prohibited or restricted
pesticide except to a person holding such a permit and then only in accordance
with the conditions which are contained in the permit.
Despite these regulations, the board is not effectively regulating
the sale, use, or application of these pesticides. The board makes few efforts
to provide information about and to enforce these regulations. As a result,
the degree of voluntary compliance with the regulations is not clear and the
178
-------
deliverate violator is pretty much free to proceed as he desires.
4. Regulation of Containers
Regulations governing the disposal of pesticide containers are the
responsibility of the Department of Public Health, and no regulations have
been promulgated. Re-use of containers is subject to the regulations of the
Pesticide Board. No nlanned efforts are made by the board r.o control the
disposal of pesticide containers. In fact, even when a significant incident
involving container disposal has arisen (see the section above on pesticide
incidents), the board has not taken action to enforce the penalties available
under existing laws. As a result, the environmental protection afforded by
existing laws, regulations, and practices cannot be considered to be adequate.
5. Regulation of Surplus Pesticides
The disposal procedures of surplus pesticides is set out in detail
in the regulations of the Pesticide Board. However, no attempts have been made
by the board to monitor such disposal and to enforce the regulations. An example
is the pesticide incident cited above in which a surplus pesticide was dumped
into a stream. In dealing with this serious violation, the board, judging
from the available record, did not consider the fact that the applicator's
original instructions to the crew to dump the surplus pesticide in a nearby
gravel pit also violated the regulations.
6. Regulation of Pesticide Accidents and Treatements
The board has not promulgated specific regulations dealing with
pesticide accidents and their treatment. However, Massachusetts does partici-
pate in the Pesticide Safety Team Network sponsored by 12 members of the
National Agricultural Chemical Association, and it is the board's policy that
the procedures necessary to utilize the emergency system be used in the case of
179
-------
pesticide accidents. Participation in the program is voluntary, however, and
the board has no authority to make parties follow its established procedures.
As a result, adequate environmental protection is not assured in the area of
pesticide accidents and treatments.
7. Factors Influencing the Use of Available Regulations
a. Financial
Lack of adequate funds, personnel, and facilities is the most
important factor influencing the degree of environmental protection presently
attained under existing laws and regulations.
b. Institutional
Lack of coordination between governmental units involved with or
affected by pesticides is another factor diminishing the degree of environmental
control that could be attained under existing pesticide laws and regulations
A lack of awareness of their potential for identifying pesticide related problems
and solutions appears to be a common characteristics of local government
agencies and of state government agencies whose primary objective is not to
effectively utilize or to control the sale, transportation, use, or applica-
tion of pesticides.
c. Social
An increasing public awareness about the use and effects of pest-
icides has prompted increased inquiries and complaints by citizens about all
aspects of pesticide sales, transportation, use, and application. Although
often based on fear and incomplete understanding, these inquiries and complaints
are a prominent factor in influencing state and local governments to more
fully use available control mechanisms to deal with pesticides problems.
Various citizen conservation groups have been especially effective in monitor-
ing the activities of state agencies, private firms, and individuals who sell,
180
-------
transport, use, or apply pesticides, and they are often well informed about the
rules and regulations and technical aspects of pesticides.
However, the major socio-economic element influencing the use of
available controls for pesticides in the Commonwealth is the relatively low
priority given to the pesticides control issue by the general public. The
concern of the general public about pesticides and critical incidents with
respect to pesticide sales, use, transportation, and application is low. As
a result, political decisions about funding pesticide control efforts turn
on the more highly charged matter of taxes and the level of overall govern-
mental expenditures. The generally low visibility of the pesticide control
issue allows the executive and legislative branches, in attempting to balance
funding requirements with all ogvernmental priorities, to give the control
of pesticide sales, transportation, use, and application a fairly low level
of priority. The lack of crisis type pesticide incidents has allowed this
situation to continue.
d. Legal
There is not sufficient legal talent and energy at the state and
local governmental levels to effectively utilize existing control mechanisms.
New regulations, administrative hearings, court cases, brief writing, and
enforcement actions often require legal inputs. With these inputs in short
supply, decisions of the executive officers of regulatory boards such as the
Pesticide and Reclamation Boards may be faulty or may not be made at all.
E. STRENGTHENING THE ENVIRONMENTAL PROTECTION AFFORDED BY EXISTING LAWS,
REGULATIONS, AND PRACTICES
1. Regulation of Sales
The most effective mechanism for regulating the sales of pesticides
181
-------
would be to provide complete information about the rules and regulations to
all who sell or distribute pesticides, to make a significant number of
observations and spot inspection visits, to back this control procedure up
with adequate technical facilities, and to objectively and strictly enforce
the laws and regulations. This is not occuring at the present time in the
Commonwealth because of lack of finances and personnel.
Moreover, recent legislation has established a licensing system
for pesticide wholesalers and distributors in Massachusetts. Licenses are to
be granted to those who meet requirements under rules and regulations to be
promulgated by the Department of Public Health. At the time of its passage,
pesticide retailers were exempted from licensing because the administrative
burden of licensing so many retail outlets was thought to be too great. Since
this passage in 1970 no rules and regulations governing the licensing have
been promulagated by the department. It is the feeling of some in the depart-
ment that the licensing procedure would be a complex and energy absorbing,
but sterile, process because there have never been sufficient personnel in
the department to monitor any of the standards set out for pesticides
registration, labeling, sale, transportation, use, and application. As a
result, the approach for regulating sales has shifted somewhat in the, department
from an emphasis on licensing to an emphasis on monitoring sales activities.
To that end, the department has had legislation filed for consideration in
the next legislative session that would authorize them to use local boards
of public health for monitoring pesticide sales in certain circumstances.
2. Regulation of Uses and Application Techniques
The Pesticide Control Board is attempting to promulgate regulations
that, if followed, will properly control the use and application of pesticides.
However, it requires a core of personnel to disseminate information, to
182
-------
monitor and spot check pesticide use, and to instigate pesticide enforcement
proceedings. The Board also needs personnel who can take samples and carry
out other technical tasks. It requires ready access to laboratory personnel
and facilities for testing samples and for the technical analysis of pesticide
related problems. Without these, the pesticides control law and regulations
dealing with uses and application techniques are empty except in so far as
investigation of reported incidents and voluntary compliance combine to make
the laws and regulations effective.
3. Regulations of Containers
The disposal of used pesticide containers is virtually uncontrolled
in the Commonwealth because there are no laws or regulations that govern it.'
The Department of Public Health is authorized to promulgate regulations in
this area. Such regulations should be written because of their value in
educating persons using pesticides as to the appropriate methods of disposal.
Also, a significant amount of voluntary compliance with such regulations is
likely.
Additional resources, as in the case of pesticides use and appli-
cations, are required, however, before the degree and precision of control
desired in this area will be forthcoming. Especially important would be the
designation of state approved sites and methods for disposing of used pesticide
containers, to include sites for treating such containers to render them
harmless before disposal.
The regulation of containers filled with pesticide material is
limited under existing law. Additional standards as to the type and speci-
fications of pesticide containers would help assure safe transport, handling
and marketing. i
183
-------
4. Regulation of Surplus Pesticides
The regulations governing the storage or disposal of surplus
pesticides appear adequate. The gap between the regulations on paper and
actual practices, however, it unknown. Additional efforts must be made to
monitor this area under the existing regulations to assure that the storage
and disposal procedures that are actually being used will not endanger people
or the environment. Again, these efforts hinge upon sufficient personnel,
finances, and facilities for strengthening information inflows and outflows
in this area and for instigating any necessary investigation and enforcement
procedures.
5. Regulation of Pesticide Accident and Treatments
More emphasis by the state government, especially the Pesticide
Board, on individuals or firms that manufacture, transport, distribute, sell,
use, and apply pesticides as to the importance of appropriate pesticide accident
reporting and treatment procedures is necessary. Fire Departments must be
trained in how to respond when dealing with pesticide fires. Common carriers
should know how to report and treat pesticide accident cases. Individuals
dealing with pesticides in any way should be more cognizant of the dangers
involved in a pesticide accident and of the way in which such accidents
should be handled. Regulations to the effect that mandatory reporting of such
accidents to the Pesticide Board be required, might be appropriate for accidents
involving common carriers. Other types of accidents, such as those which
cause waterways, food supplies, or similar items to be contaminated could be
included as accidents for which mandatory reporting would be required^
6. Control Mechanisms,
Control mechanisms written into the laws or regulations governing
pesticides include the following:
184
-------
1. Labeling
2. Registration
3. Inspection of records, equipment, and pesticide use and
application activities
4. Licensing
5. Detention, embargo, and condemnation
6. Equity proceedings
7. Fines and prison sentences
8. Bonding
9. Public notice and hearings
10. Appeals procedures
11. Civil or equity proceedings
Items one through eight are mechanisms operated by state or local
government in an attempt to attain the objective of protecting the public and
environment from harm caused by pesticides. Items nine and ten are mechanisms
operated by the government, but with the intent of providing all who have
standing with an opportunity to be heard and to challenge decisions made
by the various levels of government dealing with pesticides. Item 11 is a
mechanism for dealing with disputes between parties, often between two indi-
viduals or private firms, but sometimes between a public servant or institution
and a private individual or firm. In 1971, an act was passed an signed in
Massachusetts authorizing 10 or more persons to petition the Superior Court
it they have reason to believe that a person has damaged or is about to
damage the environment. This new liberalized policy granting any interested
parties standing to bring a cause of action on environmental matters should
increase the public visibility of pesticide incidents and force a clearer
resolution of some of the specific issues that have been handled only by the
executive personnel of the Pesticides Control and Reclamation Boards and by
185
-------
other state and local government agencies. These resolutions arrived at in
the glare of the public limelight, should have a credibility in the eyes of
the media and the public that has never been given to the less visible decisions
of the Pesticide Board. It is likely that this mechanism will become an
important means of controlling pesticide uses and application if more active
state and local monitoring and enforcement does not occur.
In the Commonwealth, these available control mechanisms are not
well used. Some, such as a labeling, registration, and licensing are formally
exercised, but their accomplishment tends to give an aura of "everything is
all right now," when, in fact, the process of receiving and logging labels,
registrations, and licenses creates a mere shell. The nature of the labels
and content of pesticides that are actually being sold in the Commonwealth
and the actual practices used by licensees in applying pesticides is not
monitored. As a result, there is little knowledge about what is really
happening with respect to pesticide sales, transportation, use, and application.
Although it is likely that there is a substantial amount of
voluntary compliance with the laws and regulations, there are circumstances
where it is in the individuals' or firms' best economic interest to violate
the laws and regulations governing pesticides activities. Where there is
little likelihood of ever being apprehended by state authorities, these
situation are likely to result in violations. Thus, the lack of knowledge
and effective control of pesticides in Massachusetts leaves the door wide
open for one or more critical pesticide incidents that might have otherwise
been avoided and for significant, but untraceable to a certain pesticide use
or incident, effects in both the short and long run on people and their
environment.
186
-------
State and local governments need to expand their use of control
mechanisms and to combine it with a larger program for providing information
to those who use pesticides and those who are affected in some way by pest-
icides. This would probably cause more use of other control mechanisms such
as detention, embargo, and condemnation proceedings, equity proceedings, and
fines. To date in Massachusetts these control mechanisms have not been used
for purposes authorized by the act regulating pesticides.
7. Coordination
There should be a significant increase in coordination between all
state and all local government agencies and individuals concerned with the
effect of pesticides on the public and the environment. For example, an
inter-departmental group including all the personnel who actually carry out
the execution and technical aspects of pesticide control policy, could be
designated at the state level. The group could meet v.'hen necessary to coord-
inate activities and to adjust practices and procedures so as to more effec-
tively attain the state's objectives in controlling pesticides. This group
should develop and implement plans to coordinate their activities and programs
with counties, cities, towns, and local agencies, such plans to be approved
by the Pesticide and Reclamation Boards.
The activities of state governmental agencies and local governments
or governmental agencies should be better coordinated. The state Reclamation
Board, for example, does not have control of or complete knowledge of the
program of mosquito control districts in practice, although it is supposed
to have such control and knowledge under the law. Board appointed commissioners
select the director of the mosquito control districts without guidelines as to
their qualifications. Moreover, the directors do not feel directly responsible
187
-------
to the board. Several directors have held their positions for some time, and
find it difficult now to openly submit their procedures for review by personne
of the board.
Cities and towns have also conducted mosquito control efforts on
an individual basis for a long time without submitting their programs to the
board for approval as required by law. Early in December 1971, the board
sent a letter to each city and town in Massachusetts explaining the existing
laws and pointing out the obligation to obtain board approval of any mosquito
abatement efforts before they are undertaken. Strong follow-up efforts are
necessary to assure that all mosquito control programs are consistent with
pesticide control policies. Such efforts, however, are unlikely because
the board has only one person to deal with all the programs and problems of
existing mosquito control districts and the activities of the individual towns.
188
-------
— ALTERNATIVE (NONPESTICIDE) METHODS OF MOSQUITO CONTROL
^ LIFE HISTQRY QF MOSQUITOES AND ITS EFFECT ON CONTROL
All species of mosquitoes undergo complete metamorphosis with four
stages of development: egg, larva, pupa and adult (imago). The large number
of species and their diversity, however, allow for great differences in the
conditions necessary for development.
1. Development Stages of the Mosquito^1'2'3'*
• Egg
The adult female mosquito selects the habitat required for the
aquatic stages of the mosquito. Some species place the eggs in permanent
bodies of fresh water, others utilize salt water, and still others lay eggs
in small temporary pools or in dry grass which will eventually be subject to
flooding. Eggs which are laid in moist areas but which do not have sufficient
water may remain dormant for months and may not hatch until the following year.
• Larva
Under the proper conditions of moisture and temperature, the eggs
hatch and the larva cuts its way out of the egg. The larva molts (sheds its
skin) four times during its growth period and the stages between molts are
called instars. Except for larvae of the genus Mansonia, all mosquito larvae
must come to the water surface co obtain oxygen. Mansonia larvae and pupae
attach themselves to the submerged roots and stems of plants and obtain oxygen
from the plant tissue. Most larvae eat small plants and animals by sweeping
them into the mouth with mouth brushes or by nibbling on the material; A few
larvae are predacious and feed on other species of mosquito larvae. The time
spent in the larval stage may be as short as A to 6 days or as long as several
months, but typically is approximately a week to 10 days.
189
-------
• Pupa
After the fourth molt, the pupal stage appears. The pupa normally
r<;sts at the water surface. When frightened, the pupa can dive with a tumbling
motion but it must return to the surface for air. Typically the pupal stage
lasts for 3 or 4 days but in some species may be 2 weeks or more.
• Adult
The adult breaks the pupal skin and emerges slowly, using the
cast-off skin as a float until its body dries and hardens. Female mosquitoes
are able to suck blood from an appropriate host organism. Male mosquitoes are
not equipped to suck blood. Many species of mosquitoes attack man but others
attack wild and domestic animals, and some attack nonmammalian species, such
as birds, amphibia and reptiles. Depending on the species of mosquito, mating
between males and females may take place at rest on some object, such as a
shrub or grass, or while flying. Females of several species may pass the winter
in hibernation in a protected place whereas others overwinter in the egg stage
or even in the larval stage.
2. Effect of Life Cycle on Mosquito Control
The life cycle of the mosquito is illustrated in Figure IX-1.
Depending on the species of mosquito and the temperature, the total time for a
complete life cycle may typically vary from 16 days to 45 days if environmental
conditions are reasonably satisfactory for all stages of the life cycle. On
the other hand, lack of suitable conditions may lengthen the life cycle dramati-
cally. For example, Aedes species may lay eggs in places which are above the
existing water line and which may not be flooded until the following year.
Thus, instead of hatching in a few days, the fertilized egg will remain dormant
for several months until it is covered with water. Water temperature has an
effect on the time required for hatching of eggs and development of the larvae.
190
-------
V
EGG (Approximately 3 days to hatch.)
"
LARVA (1st, 2nd, 3rd and 4th INSTAR stages. Larval stages
usually last a total of 4 to 10 days.)
Y
PUPA (Pupal stage usually lasts 3 or 4 days but may be two
weeks in some species.)
ADULT (Male and female mating; fertilized female takes blood
J
meal and in a few days is ready to lay eggs.)
FIGURE IX-1. LIFE CYCLE OF THE MOSQUITO. (Typical life cycle
requires 16 to 30 days but cold weather may extend
it to 45 days or even over winter in some species.)
191
-------
Low temperatures inhibit the development of larvae, sometimes to such an
extent that some species overwinter in this stage. Extremes of temperature
both high and low can kill the mosquito in the egg, larval or adult stage.
While mosquitoes are subject to attack by predators, parasites
and diseases both in the aquatic stages and as adults, control by natural
enemies or by artificial means is extremely difficult. In an area such
as Cape Cod there may be 25 or more species of mosquitoes all with different
life cycles, breeding places, and seasonal preference. In addition, the rate
of hatching and growth of various species may be dependent on uncontrollable
conditions, such as temperature and rainfall.
B. NATURAL ENEMIES OF THE AQUATIC STAGES OF THE MOSQUITO
• Plants
Certain aquatic carnivorous plants will trap mosquitoes and other
plants may inhibit mosquitoes by covering the surface of the water and blocking
access to air or by producing toxic by-products. Sometimes the inhibition may
simply be due to an excess liberation of oxygen which can change the microflora
of the water and may also bring in predacious fish.
Two algal species (Chara elegans and Cladophora glomerata) have
[4]
recently been described which produce inhibitory substances that prevent the
growth of mosquito larvae, possibly by attacking the lining of the larva's
alimentary canal. While Dr. Reeves indicated that the algae apparently control
mosquitoes in streams in xrtiich they grew, much additional research is required
to elucidate the structures of the inhibitory substances, their mode of action
and the feasibility of making and using the substances in practical mosquito
control.
Garlic extracts have been shown to be larvicidal and two substances,
diallyl disulfide and diallyl trisulfide, have been isolated and identified as
the larvicidal principles .
192
-------
• Lower Forms of Animal Life
Hydra may destroy larvae and Vorticella may cause the death of
larvae by excessive growth on their bodies.[2] Water snails may feed
on mosquito eggs and water fleas (Daphne) may destroy larvae.[2]
• Arthropod Predators
Arthropod predators such as Limnesia have been reported to attack
young mosquito larvae. In the order of Coleoptera (beetles) larvae of
Hydrophilidae and Gyrinidae. as well as both adults and larvae of
Dytiscidae, ' ' are natural predators. Dragonf lies' •* (Odonata) are
well-known predators on adult mosquitoes but their larvae also attack certain
mosquito larvae. Various bugs1 ' ^ (Heroiptera) are also active in destroying
mosquito larvae.
• Cannibal Mosquito Larvae
[2]
The larvae of a number of mosquito species, such as Psorophora,
Lestiocampa, Corethra, Eucorethra, Mochlonyx, and Chaoborus, have cannibalistic
habits and eat larvae of other mosquito species.
• Fish
Among the most effective of all natural enemies of mosquitoes are
small larvivorous fish. The tropical or semitropical mosquito fish (Gambusia)
has received the most attention. However, other fresh water and brackish water
fish are also instrumental in the natural control of mosquito populations.
Because fish have been used fairly successfully in the control of mosquito
populations in certain areas, the subject will be discussed at greater length
in a following section.
• Other Vertebrates
Frogs and toads and their tadpoles are not usually larvivorous but
strc
[2]
[2]
some species have been known to destroy mosquito larvae. Ducks and other
aquatic birds also destroy larvae.
193
-------
C. NATURAL ENEMIES OF THE ADULT MOSQUITO
[8]
Spiders capture the adult mosquito by catching them in their webs.
[12]
Dragonflies and certain wasps are able to capture flying mosquitoes on the
f 21
wing. Among the vertebrates, frogs and lizards have been observed to feed
[ 2]
on adult mosquitoes. Bats and many species of birds such as swallows and
[2]
martins can capture mosquitoes in flight.
D. NATURAL PARASITES
Because the eggs, larvae and pupae of most species develop in highly
contaminated water which contains a rich flora and fauna, mosquitoes are usually
exposed to a variety of natural parasites at the various life stages. These
parasites include microorganisms such as molds and bacteria, gregarines,
flagellates, microsporidia, ciliates, trematodes, nematodes, and even mites
[21
and diptera. While the effects of these organisms are a definite burden to
the mosquito, they usually are not sufficient to eliminate mosquitoes except
in a very highly localized condition. However, their major effect is to prevent
population explosions, and well-conceived control programs will promote their
growth.
E. EMPLOYMENT OF NATURAL ENEMIES FOR MOSQUITO CONTROL
1. Fish
Prior to the development of effective chemical pesticides, (and more
recently in atvampting to avoid their ecological effects), attempts have been
made to employ various natural enemies of the mosquito in managed mosquito
control programs. To date, fish have been the most successfully employed natural
enemy of the mosquito. Gerberich prepared an annotated bibliography of
papers relating to the control of mosquitoes by the use of fish, and it con-
tained 298 references that had appeared in the literature up to 1942. The
1966 revision by Gerberich and Laird contained 686 references. According
194
-------
to Bay, 41% of the papers deal largely or exclusively with Gambusia,
8.6% with the Southeast Asian fish, Panchax. 6.5% with the common guppy and
"after that few of the remaining 200 to 300 species occupy more than 2%."
The mosquitofish, Gambusia. is a natural inhabitant of fresh water
in southern areas of the United States. (The taxonomy of the mosquitofish
is somewhat confused but is well-discussed by George.)^17] Species of
Gambusia have been transferred from the South and introduced into other areas
of the country. A cold-adapted variety of G_. affinis has been successfully
introduced into northern regions including Ohio, Michigan and Illinois.
Under proper conditions, Gambusia may give almost complete control of mosquito
[14]
population. However, in its native habitat in southern U.S., large numbers
of Gambusia have been observed to live together with also large numbers of
mosquito larvae, indicating that a natural balance has been reached. In the
appendix to his thesis, George also describes the dissemination of the
mosquitofish in North America and its utilization in mosquito control.
In New England and other northern areas where the winters are too
cold for Gambusia to survive, certain native fish are also effective in reducing
mosquito populations. In brackish water (including some areas on Cape Cod in
this study), the salt water killifish or mummichog, Fundulus heteroclitus, is
used to destroy mosquito larvae. The effectiveness of mummichogs in controlling
mosquitoes can be greatly increased by the presence of natural or artificially
produced holes several feet in diameter and a few feet deep which can retain
water and offer sanctuary to the population of mummichogs as the tide recedes
from the salt marshes. When the tide returns, the fish are in good position to
resume activity.
2. Plants
While the use of plants in mosquito control has been studied for
195
-------
risi
many years, J the subject is a complicated one because some species are
themselves pests and others can increase production of mosquitoes instead of
decreasing them. However, Bay' ^ believes that "next to fish, aquatic
plants, where applicable, probably hold the most important practical potential
for naturalistic mosquito control."
3. Other Predators, Parasites and Pathogens
The release of large numbers of bats or predacious arthropods also
does not seem practical at this time and much additional research is required.
Likewise most naturally occurring pathogens of mosquitoes usually attack
[ 191
relatively small proportions of wild populations. J Despite these problems
research is proceeding and promising laboratory results are being obtained
[211
with microsporidia and nematodes by USDA researchers at Gainesville, Florida,
and Lake Charles, Louisiana. Additional laboratory and field work is required
before these potential control measures can be practically evaluated.
F. CONTROL BY ALTERATION OF LIFE CYCLE
1. Sterile Male Release
The release of sterile males has been successful with a limited number
of other insect pests, such as the screwworm and tropical fruit flies. However,
the control of mosquitoes by this method is complicated by the large numbers of
species, the variation in length of life cycle, and the effects of temperature
and rainfall on the time of emergence. Much more research will be needed in
order to raise a large number of mosquito species economically and separate
the sexes. Large numbers of sterile males have to be released to overwhelm
the natural populations even when that population has been reduced by prior
use of pesticides. The released males must be competitive with the males
in the natural populations. At the present time it does not appear practical
to control all species of mosquitoes in a given area by sterile male release
196
-------
but one or two especially troublesome species might be controlled in this
t20»
manner.
2_._ Sterilization of Males or Females in Natural Habitat
While chemical or radiation sterilization in the natural habitat
is theoretically possible, we do not yet have safe and innocuous methods that
would not endanger other species. Also, safe and specific attractants will
be necessary to attract the wild species to the place at which they would be
sterilized.
Chromosomal translocations have been studied as a method of intro-
F231
ducing sterility into a natural population. L J Double translocations appear
to be much more effective than single translocations and have approximately
the same theoretical effectiveness in reducing mosquito populations as the
sterile male technique. Again much laboratory and field work remains to
be done.
3. Hormones
Synthetic materials which mimic hormone activity have recently
been reported. '' These products may stop the growth of mosquitoes in
the larval stage or in the pupal stage and thus break the life cycle. While
these materials show great promise, they are still in an experimental stage,
some are easily destroyed by sunlight and it will take time to assess their
true value.
A. Attractants
Sex attractants or oviposition attractants may possibly be useful
in attracting adult mosquitoes to traps. Again these materials have only
been partially investigated and to date no commercially available products
are known which are useful with mosquitoes.
197
-------
G. MECHANICAL METHODS OF MOSQUITO CONTROL
1. Drainage and Flooding
One of the most effective ways of controlling mosquito populations
has been the selective and partial drainage of swampy areas to remove standing
pools of water J2?] Often the number of breeding places for mosquitoes can
be drastically curtailed while still not interfering with other wild life,
such as ducks, fish, etc., that inhabit marshes and swamps. Conversely,
where a large flow of water is obtained, either fresh water or that from
tides, mosquito larvae may be swept out of the area by rapid flooding of
[27]
the breeding area.
2. Traps
Traps for female mosquitoes have not been well-developed, probably
because of a lack of information on the specific attractants required in order
to entice them into traps.
3. Screening
While screening is usually thought of as keeping female mosquitoes
away from their human victims, screening can keep the female of house-dwelling
mosquitoes away, from areas for egg-laying.
4. Insoluble Monolayers
Biodegradable lipids or lecithin spread at the extremely low
concentration of approximately .1/2 ounce per acre of water has been shown to
r 28i
smother pupae of several mosquito species. Larvae are not asphyxiated
because the lipid film is easily penetrated by the small larval spiracle,
but pupae cannot pierce the film. If a cheaper source of lecithin, such as
cottonseed lecithin, can be used, the method may be attractive since the
material would be nontoxic and does not interfere with the transfer of
oxygen from the air to water. Its use seems most appropriate for small,
198
-------
protected still water sites, and not for open bodies of water where wave
action or tidal flow would tend to destroy the film.
H. PESTICIDE USES CONSIDERED ESSENTIAL FOR ACCEPTABLE CONTROL
In New England, control programs using natural means are already
well-developed, and have reduced mosquito populations in many areas. Care-
fully planned and maintained ditches are used to reduce the number of pools
and puddles where female mosquitoes lay their eggs. In salt marshes, holes
are dug for predacious fish to provide sanctuary far from normal water
channels during low tide and to insure their presence at high tide. Nesting
boxes are provided for birds which prey on mosquitoes, in areas of high popula-
tion probability, and encourage them to stay in the area.
Even with the use of all these methods, it is still necessary to
use pesticides to gain acceptable control of mosquitoes that will prevent
spread of EEE. In the critical areas of Southeastern Massachusetts, weather
patterns in some seasons minimize the effects of natural controls and require
frequent application of pesticides. In extreme cases wide areas need to be
treated, but in normal situations only spot treatment of selected swamps and
marshes is necessary. We believe that a good larvaciding program, properly
conducted, will control most mosquito populations and preclude the need for
adulticiding programs.
A significant feature of developing good larvaciding programs is
the potential for use of nonchemical, degradable mineral oils (such as Flit MLO)
which have only minor acute effects on nontargel species and minimum residual
effects. Larvaciding with such products will kill or prevent larvae from
developing properly by sealing off their oxygen supply. By thus breaking the
life cycle, control of several generations can be effected and the control of
several species potentially can be realized with one application. The major
199
-------
drawback of mineral oils is their tendency to disappear in 2-3 days, making
retreatment necessary in periods of rainy weather.
In more difficult cases, it may be necessary to use rapidly de-
gradable, nonresidual chemical insecticides (such as Abate, malathion,
naled, carbamates) in larvaciding programs. Slow-release formulations of
these materials will provide extended control for longer periods during rainy
weather and reduce the number of applications necessary for acceptable control.
The slow-release feature means that only small quantities are solubilized at
any given time, reducing the danger of harming other organisms and not over-
loading the degradation system.
200
-------
BIBLIOGRAPHY
1. Carpenter, S.J., LaCasse, W.J., "Mosquitoes of North America,"
Univ. of California Press, Berkeley, 1955.
2. Christophers, S.R., "Agdes Aegypti (L.)," University Press,
Cambridge, 1960.
3. Bates, M., "The Natural History of Mosquitoes," The Macmillan
Company, New York, 1949.
4. Reeves, E.L., Amonkar, S.V., Sci. News, 100, 63 July (1971).
5. Reeves, E.L., private communication.
6. Amonkar, S.V., Reeves, E.L., J. Econ. Entomol., 63, 1172 (1970).
7. Amonkar, S.V., Banerji, A., Science, 174, 1343 (1971).
8. Laird, M., Trans. Roy. Soc. N.Z., 7^L> 453 (1947).
9. Twinn, C.R., Can. Entomol., 63^ 51 (1931).
10. Baldwin, W.F., James, H.G., Welch, H.E., Can. Entomol., £17, 350 (1955).
11. James, H.G., Can. J. Zool., 43, 155 (1965).
12. Corbet, P.S., "A Biology of Dragonflies," Witherby, London, 1962.
13. Hinman, E.H., J. Trop. Med. Hyg., 37, 129 (1934).
14. Bay, E.C., Calif. Mosq. Cont. Assoc. Proc., 35., 34 (1967).
15. Gerberich, J.B., Amer. Midi. Natur., _36, 87 (1946).
201
-------
16. Gerberich, J.B., Laird, M., An annotated bibliography of papers
relating to the control of mosquitoes by the use of fish
(revised and enlarged to 1965). WHO/EBL/66.71, WHO/Mal/ 66.562.
17. George, C.J.W., Ph.D. Thesis, "Behavioral Interaction of the Pickerel
and the Mosquitofish," Harvard University, Cambridge, Mass., 1960.
18. Matheson, R. , Arner. Natur., 64, 56 (1930).
19. Kellen, W.R., Calif. Mosq. Cont. Assoc. Proc., 3,1, 23 (1963).
20. Weidhaas, D.E., personal interview, USDA, A.R.S., Gainesville, Florida,
January, 1972.
21. Hazard, E.I., Lofgren, C.S., J. Invertebr. Pathol., 1£, 16 (1971).
22. Patterson, R.S., Weidhaas, D.E., Ford, H.R., Lofgren, C.S.,
Science, 168, 1368 (1970).
23. Laven, H., Nature, 221, 958 (1969).
24. McElheny, V.K., Technol. Rev., July/August, 12 (1971).
25. Anon., Chem. & Eng. News, Nov. 29, 9 (1971).
26. Anon., Chem. & Eng. News, Nov. 29, 33 (1971).
27. Springier, P.F., Mosq. News, 24, 50 (1964).
28. McMullen, A.I., Hill, M.N., Nature, 234, 51 (1971).
U.S GOVERNMENT PRINTING OFFICE: 1972 484-487/3511-3 202
------- |