54077501
ESTABLISHMENT & REVIEWS OF ORIGINAL KEPONE ACTION LEVELS
ENVIRONMENT/I PRCTECTi'JN AGEiJCY
OFFiCZ OF ?E37:C.:i PROGRAMS
REG.STSAL'O.N' ui-.';3,C;i (WH-567)
WASHINGTON, O.C. 20460
1977
TIARY
:6!:i-^TAL PROTECTION
^ - OS317
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ESTABLISHMENT & REVIEWS OF ORIGINAL KEPONE ACTION LEVELS
Table of Contents
1. Introduction: Evolution of the Problem and Brief Chronology
of EPA Response
2. Considerations in Establishing Current Action Levels
a. Toxicological Considerations
b. Analytical and Residue Chemistry Considerations
3. New Considerations in Revising or Continuing Current Action Levels
4. Results of Reassessment and Recommendations
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INTRODUCTION:
j. Evolution of the Problem and Brief Chronology of EPA Response
In mid-1975, the Atlanta Center for Disease Control, in conjunction
with Virginia , discovered that several Life-Science Products Company (LSPC)
workers were seriously ill due to massive occupational exposure to Kepone.
Kepone residues from .02 to 60 parts per million CppmT were found in both
blood and sebum samples from all 28 hospitalized LSPC workers, in addition
to one worker's wife who had also been hospitalized.
Kepone levels of 0.1 to 4 parts per billion (ppb) were found in the
James River. Kepone residues ranging between 0.1 and 20 ppm were found
in fish and shellfish in the Games River, some from samples as far as
40 miles away. Bottom sediments, soils, and sludge were also tested with
positive results. Filters gathered between March of 1974, and April 1975,
from the State air sampler station located approximately 200 yards from
LSPC operation contained residues ranging from 0.2 to 50 micrograms per
cubic meter of air. Tap water from the Hopewell water supply was also
tested; fortunately, no detectable levels of Kepone were discovered there.
As a result of the water media samplings, Governor Godwin of Virginia
closed the James River to fishing the following day.
On August 20, EPA Region III issued an order to LSPC under the authority
of the Federal Insecticide, Fungicide and Rodenticide Act, to stop the
sale or use, of Kepone, as well as its removal from the premises. On
February 3, 1976, a similar order was 'issued to the Baltimore facility
of Allied Chemical Corporation.
EPA's Environmental Research Laboratory in Gulf Breeze, Florida,
(ERL/GB) has established the cleansing ability (depuration) of trans-
planted seed oysters. Data obtained from the State and corroborated by
ERL/GB indicate the James River seed oysters depurate Kepone. The James
River supplied 90 per cent of all the seed oysters in Virginia, of which
50 per cent of that amount is exported. Seed oysters are transplanted to
various growing areas and reach marketable size in two to three years.
In February 1976, EPA recommended to the FDA "action levels" or allow-
able temporary levels of pesticide residues used as enforcement guides,
of 0.3 parts per million (ppm) of Kepone in the edible portion of shell-
fish (oysters and clams) 0.1 ppm in finfish, and 0.4 ppm in crabs. EPA
also recommended a 0.03 ppm action level in processed oyster stew. These
recommendations were made using classical estimate procedures for threshold
effects described in the next section of this paper. At that time, EPA
committed itself to further consideration of this action level for possible
revision if new data warranted it.
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2.. Considerations in Establishing Current Action Levels
There are at least three major considerations in adoption of action
levels. First, toxicological, i.e., human safety, considerations are
overriding. Second, there are analytical and residue chemistry considera-
tions, which are necessary to establish or confirm analytical method(s)
to enforce the action level. A third consideration is economic loss,
i.e., what percentage of the fish and shellfish production will be rendered
unfit by the action level.
A. Toxicological Considerations
The procedure used by the Toxicology Branch of EPA-OPP's
Registration Division to develop recommended action levels for
Kepone in finfish, shellfish and blue crabs was analogous to
the procedure used for establishing the acceptability of pesticide
tolerances. The following data were reviewed when the Kepone
action levels were originally recommended and were rereviewed
for this reassessment:
1. Acute Stuci'es
a. Oral L05Q - Feb. 9, 1959
b. Dermal LD5Q - Feb. 9, 1959
2. Subacute Studies
a. 21-Day Oral - Rat - Feb. 9, 1959
b. 90-Day Oral - Rat - Feb. 9, 1959
t
3. Chronic Studies
a. 2-yr. Rat Feeding - July 1961
b. 2-yr. Dog Feeding - Feb. 1962
c. Mouse Reproduction - 1965
d. NCI Verbal Oncogenic Report - Fall 1975
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The initial correspondence in our files dates back to 1958 and some
reports are undated. Therefore the dates qiven above are approximations
in some cases.
In summary, the original review of the data indicated that:
1. Kepone is not acutely toxic and would be placed in toxicity
Category II for labeling purposes. This catenory classification
gives no indication of the subacute and chronic toxicity of
the chemical.
2. There is evidence that Kepone is a cumulative toxin at relatively
low levels (approx. 5 pom in rats) and that.within a three
month period 5 pom produced a ID ppm fat residue and 80 ppm
produced a 400 ppm fat residue.
3. Tremors, characteristic of chlorinated hydrocarbons, occurred
at 25 ppm in chronic feeding study. Testicular atrophy and
estrogenic effects were evident at this level in rats and mice
resulting in sterility in both sexes. Females appear more
susceptable to Kepone in all mammalian species tested. Ten
ppm is hepatotoxic in females.
4. In a two-year rat study, 10 and 25 ppm may have produced
hepatocarcinoma in both sexes. Preliminary information from
NCI lends credence to this suspicion. Kepone produced a 24%
incidence in female rats and approximately 80% in both sexes
in mice at levels from 5 to 40 ppm. It appears that Kepone
must be considered as a highly suspect carcinogen.
5. At 1 ppm in the rat a slight increase in proteinuria was noted
and the severity increased with dose. Therefore the MEL of
1 ppm in rats reported by Allied Chem. is questionable.
6. Preliminary analysis of Kepone residues in shell fish and fin
fish indicated levels near and above the questionable rat NEL.
The recommended Kepone action levels for fin fish, shell fish and crabs
were developed in the following manner using a method analogous to
tolerance acceptability calculations.
A. Determination of Maximum Permissible Intakes (MPI)
1. Using the questionable 1 ppm "no effect level" from the
two year rat feeding study and several safety factors
.(SF) a MPI was calculated for a 60 kg human. (1 ppm in
rat diet = 0.050 mg/kg body weight/day)
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Safety Factor SF Value (Rat) HPI (Man, 60K)
mg/kg bd. wt/day mg/day
TOO
500
1000
2000
0.0005
0.0001
0.00005
0.000025
0.03
0.006
0.003
0.0015
2. Sample calculations:
a. Determination of safety factor value
•
0.050 mg/kg/day » 0.00005 mg/kp/day
1000
b. .Determination of MPI
0.00005 mg/kg/day X 60 kg = 0.003 mg/day
B. Determination of Food Factors (FF) for each of the food items
in the daily diet of man. (FF = % in daily diet)
1. Fin Fish (Fresh and Frozen, edible weight)
a. Per capita consumption 1973*
5.1 Ibs/yr X453.6 gr = 2313 gr/yr
b. Per capita consumption/day
2313 •? 365 = 6.34 gr
c. % of 1500 gr total daily diet
6.34 * 1500 = 0.42%
2. Shell Fish (Fresh and Frozen, edible weight)
a. Per capita consumption 1973*.
2.1 Ibs/yr X 453.6 gr = 952.6 gr
b. Per capita consumption/day
952.6 gr * 365 = 2.61 gr
c. % of 1500 gr total daily diet
2.61 * 1500 = 0.17%
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3. Blue Crabs
a. Per capita consumption 1969**
0.213 Ibs/yr X 453.6 gr = 96.6 gr/yr
b. Per capita consumption/day
96.6 T 365 = 0.26 gr .
c. % of 1500 gr total daily diet
0.26 r 1500 = 0.02%
Pef 2
* ™S, Consumption, Prices, Expenditures Supolement for
1973 to Agn. Eco. Report .Mo. 138, USDA-Eco. Res. Ser.
Table 9, p. 17, Dec. 1974.
** USDC Nat. Marine Fisheries Ser. Circular 361 (1969).
C. Determination of the Theoretical Maximal Residue Contribution
(TMRC) of the recommended action levels to the cl.iily diet,
assuming that the maximum allowed residue will be present
in the food when consumed.
1. Fin Fish (action level 0.1 ppm= 0.0001 mg/kg of diet)
0.0042 X 1500 gr X 0.0001 mg = 0.0006 mg
2. Shell Fish (action level 0.3 ppm = 0.0003 mg/kg of diet)
0.0017 X 1500 gr X 0.0003 mg = 0.0008 mg
3. Blue Crabs (action level 0.4 ppm = 0.0004 mg/kg of diet)
0.0002 X 1500 gr X0.0004 mg = 0.0001 mg
D. Comparison of TMRC with the MPI to determine acceptability
of recommended action level (SF = 1000).
Food Item Action Level TMRC MPI
ppm mg/Total Diet mg/day
Fin Fish 0.1 0.0006 0.003
Shell Fish 0.3 0.0008 * 0.003
• Blue Crabs 0.4 0.0001 0.003
T=0.0015
In each case the recommended action level produces a TMRC lower
than the MPI derived with a 10COSF and leaves room for additional
action levels for other food items if the necessity arises (total
TMRC = 0.0015 mg/day vs 0.003 mg/day).
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b. Analytical and Residue Chemistry Considerations
The only previous tolerance actions on Kepone were a temporary
tolerance of 0.1 ppm on potatoes (expired) and a current tolerance
of 0.01 ppm on bananas. The banana tolerance represents analytical
sensitivity and was based on the Registration Division's Chemistry
Branch's assurance to Toxicology Branch that there would be no real
residues in edible parts.
(a) The Regulatory method for bananas (PP# OE0919), was published
in the Pesticide Analytical Manual (PAt ) Vol II, and validated on
banana peel and pulp. The method's estimated sensitivity is 0.005 ppm.
The principle of this method involves isopropanol/benzene extraction,
fuming sulfuric acid cleanup, base partitioning, and MC or EC gas liquid
chromatography (GLC). The procedure is said to be applicable for certain
other fruits, vegetables, milk with modifications for oily samples.
(b) HERL method(s): The HERL procedure is actually a system
of alternative extraction, cleanup, determinative, and confirmatory
procedures have been used in various combinations. For fish and
shellfish, the basic procedure was: extraction of lOg sample with
25% toluene/Et acetate, cleanup by micro Florisil column or gel
permeation, or base partitioning. Measurement is by GLC with any
of 5 optional GC columns and any of 4 detectors. Some analyses
have been confirmed by GC/Mass spectrometry with chemical ioniza-
tion.
The sensitivity of the overall procedure appeared to-be about
0.01 ppm in fish and shellfish, judging from the residue values
reported. However, based on conversation with Dr. "-loseman, Analyti-
cal Branch, HERL, this sensitivity may not always be attainable.
Raw data (chromatogram) has been requested from HERL so that it will
be possible to gauge the minimum response in relation to background.
The alternative procedures were used to provide additional assurance
through comparison of results. Reasonable agreement on replicate
samples by the alternative procedures was obtained on most samples
and there is no reason to question accuracy of results.
(c) FDA multiresidue methods: Kepone had not been sought in
any FDA regulatory program, including the Total Diet Study. Its
behavior has not been sufficiently studied in the PA1 (FDA) mul-
tiresidue method for chlorinated hydrocarbons. Preliminary studies
indicate that it is not detected by the method, either because it is
not eluted from the Florisil column or does not have a favorable
partitioning co-efficient in the acetonitrile/hexane partitioning
step. FDA Headquarters was then devising a method to be used by
the District Laboratories in the current Kepone situation. It
seemed likely that they would go with some version of the current
multiresidue method to minimize impact on their pesticide program.
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(d) Other methods: There have been a few reports in the literature
of other methods for Kepone but these appeared to be of limited interest.
(Arant, F.S.J Econ. Ent. 60:925-7, 1967)
3. Residues in fish and shellfish in James River area (HERL data)
Fin fish examined were fresh water or anadromous species only. Kepone
residues ranged from 0.01-0.2 ppm in bottom feeders and trace to 3 ppm
in predator fish. These residue values apparently art based on the
whole gutted fish. Any action level adopted would be on a similar
basis because the FDA Manual describes the fish sample to be "headed,
gutted, and scaled." Separate analyses were made by HERL on entrails
and liver with correspondingly higher residue findings.
No data were presented on salt water food fishes (flounder, striped
bass, blues, seatrout) which might be expected within the sampling
area. This omission has some practical significance in regards to
setting action levels. Consumer hazards arising from fresh water
fish could be controlled (without action levels) by imposing fishing
restrictions on local waters, the salt water acting as an effective
barrier to migration from the quarantined area. The risks from
consumption of the migratory salt water food fishes taken after
residence in the James estuary would have to be controlled by an
action level implemented in a national surveillance program since
the fish might be taken elsewhere in Chesapeake Bay or long the
East Coast. Levels found in clams and oysters were comparable and
ranged from 0.2 to 0.8 ppm. No analyses of crabs were made.
The available data (total of about 26 samples) did not permit any
statistical evaluation as to distribution of residue levels in fish
or shellfish populations within the contaminated area during the
period of sampling. Neither was the sampling adequate to indicate
residue decline rate. Both factors are important considerations
in selecting an action level because they determine the extent of
economic loss, i.e., a given action level renders x% of the fish
population violative at a given time.
We had little or no information on any alterations Kepone may
undergo in water or marine organisms. A rat metabolism study
indicates it is fairly stable in mammals. The related compound
Mirex is known to degrade under sunlight or UV light to Kepone
and further Cl 9 and Cl 10 degradation products of Kepone.* On
the basis of present information, Kepone per se must be considered
the residue of concern in fish and the action level should reflect
this.
*G.W. Ivie, H.W. Dorough, E.G. Alley, J. Ag Food Chem 22 no. 6, 1974
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4. New Considerations for Revising or Continuing Action Levels
Current Action Levels
Dsequent to the above review the Toxicology Branch received the NCI
rcinogenesis Bioassay'Report on Technical Grade Chlordecone (Kepone).
summary of the results, provided by NCI, confirming the suspicion
ised by the two year rat study follows:
"A carcinogenesis bioassay of technical grade chlordecone (Kepone)
• was conducted using Osborne-Mendel rats and B5C3F1 mice. Chlordecone
was administered in the diet for 80 weeks at two dose levels, with
the rats sacrificed at 112 weeks and the mice at 90 weeks. The
starting dose levels were 15 and 30 ppm for male rats, 30-and 60 ppm
for female rats, 40 ppm for male mice and 40 and 80 ppm for female
mice. As these dose levels were-not well tolerated, the dose levels
were reduced during the course of the experiment such that the
average dose levels were as follows: 8 and 24 pom for male rats,
18 and 26 ppm for female rats, 20 and 23 ppm for male mice and
20 and 40 ppm for female mice. Clinical signs of toxicity were
observed in both species, including generalized tremors and
dermatologic changes. A significant increase (P .05} was found
in the incidence of hepatocellular carcinomas of high dose level
rats and of mice at both dose levels of chlordecone. The incidences
in the high dose groups were 7% and 22% for male and female rats
(compared with 0 in controls for both sexes) and 88% and 47% for
male and female mice (compared with 16% for male controls and 0
in females); for the low dose groups of mice the incidences were
81% .for males and 52% for females. In addition, the time to
detection of the first hepatocellular carcinoma observed at death
was shorter for treated than control mice and, in both sexes and
both species, it appeared inversely related to the dose. In
chlordecone-treated mice and rats extensive hyperplasia of the
liver was also found. The incidence of tumors other than in the
liver for chlordecone-treated.groups did not appear significantly'
different from that in controls."
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More recent food consumption values were used for finfish and shellfish
than in the first recommendation; therefore, the figures presented than
differ slightly from previous derived quantities. The differences do
not change the recommended action levels for each food item previously
developed. With the exception of the NCI carcinogenesis Bioassay
Report, summarized below, no new toxicological data has been received
by the Toxicology Branch since the original recommendation.
In the previous evaluation it was concluded^that an action level of 0.02 ppm
for fish, clams and oysters could be supported with available analytical
methods. This represented a bottom line figure subject to increase by
toxicology and economic impact considerations. The figures which sub-
sequently issued were 0.4, 0.3, 0.1 ppm on crabs, oysters and fin fish,
respectively.
Given the present state of the methodology for Kepone, a 0.02 ppm
action level could still be supported if new toxicology information
requires such a reduction from present action levels. That is, residues
on the order of 0.02 ppm can be measured when analytical procedures are
carefully controlled. However, experience gained with the methods during
the intensive 1976 sampling program, including an inter!aboratory quality
assurance (check sample) study, suggests that a level of 0.05 ppm should
be the lowest level at which any regulatory action should be taken.
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retailed Considerations
1. Commodity definition
n
l. I Sec. 141.12
and are found in FDA RAM Vol.
(al fin fish and eel discard head, tail, fins, scales, inedible
* bones and entrails, analyze with skin (except fish with
inedible skin)
(b) oysters, clams: examine homogeneous mixture of
,-neats end liquor, (exclude shell liquor.)
(c) crabs: Discard shell and viscera, examine edible
portion including fatty deposits in wing tins.
(for soft crabs use whole crab)
2. Chemical entity measured
Although certain rearrangements of Kepone-Mirex have been reported,
there is still no information on significant metabolites occurring
in marine organisms and the residue of concern is Kepone per se.
It is measured against reference standard (EPA # 7) in tetrahydrate
form (corrected to anhydrous Kepone.)
3. Improvements in methodology
Significant advancements have been made in Kepone methodology in
1976. The advancements, however, may be characterized as refine-
ments and validation of available -methods rather than any breakthroughs.
Several analytical workshops between EPA (KTP, Gulfbreeze, and RD) ,
FDA, Virginia State laboratories, and Maryland were instrumental in
eliminating numerous and troublesome optional extraction, cleanup,
and determinative steps employed in the various labs in early 1976.
From these meetings there emerged a more or less standardized analyt-
ical method and useful agreement on sample preparation and use of re-
ference standards.
Tne method of choice for fish, shellfish, and crabs is based on the
Allied Chemical Co. method as described in PAM Vol. II for bananas.
A modification of this method was devised by Chemistry Branch, PD,
and used in the analyses of 60 fish samples for the State of Va.
A paper on this method was presented by Mr. Watts, CHM at a symposium
in Williamsburg VA. in May.
FDA was not successful in incorporating Kepone into their multi-
residue schemes. They have devised for their regulatory program a
modification of the same method (PAH II), described above (see
program circular 7320. 79A, attach. C). It is this method which
will be used to enforce Kepone action levels and it would be adequate
to enforce an action level of 0.05 ppm. Principle: isopropanol/
benzene extraction, fuming sulfuric acid cleanup, base partitioning,
and GC/EC detection.
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Analysis of 1976 residue data on^ fish. ,shellfish_r and crabs
Through the soring, summer, and fall of 1976 several major sampling
programs were carried out. The first of these was coordinated by the
Virginia Division of Consolidated Laboratory Services. The cooperat-
ing laboratories were KTP-EPA; Gulfbreeze-EPA, Registration Divison
(CHM)-EPA, Annapolis-EPA, FDA Baltimore District and Virginia Insti-
tute of Marine Sciences (VIMS). Sampling in this program was mainly
in the lower bay and tributaries. The State of Maryland established
a Kepone Task Force and conducted sampling, mostly in the upper bay.
The FDA initiated a program calling for analyses of 304 samples of
Kepone (and Mirex) through October 29, 1976. These samples were to
be collected from commercial markets, with primary emphasis on Bay
fish, but also so.me sampling of migrant bluefish along the east
coast and some in the fire ant areas (Gulf Coast) to investigate
possible Kepone residues from Mirex usage.
Much of the data from these programs seems to have been freely
interchanged, but we are not aware of any comprehensive summary of
the 1976 sampling program. Such a sum-nary could provide a base for
predicting the level of residues likely to occur in Say fish pop-
ulations in 1977, and.most importantly, what Percentage of the
catch would fall within action levels.
Certain statements in the files indicate that such statistical
analyses may have already been made. Example: Gov. Godwin "amonq
all species of finfish tested.... samples above action level ranged
from 7 to 16 ," (Richmond News Leader 10/13/76). Also, the National
Fisheries Institute and Virginia Seafood Council (letter of 10/14/76,
L.J. Weddig, Exec., Dir. in letter to J. Blanchard) says 14.2 of
all species were above action level.
Attachment A is a statistical evaluation of the distribution of residues
in fish, shellfish, and crabs. The evaluation is based on all the
data available to us as of 12/23/76. It includes all of the
residue data generated in the 1976 FDA regulatory program, data
from the Maryland Kepone Task Force, and data from the program
coordinated by the.Virginia Division of Consolidated Laboratory
Services, including 60 analyses made by our CHM laboratory,
RTP, and Gulfbreeze. The Virginia data may be incomplete.
The data base includes a total of about 470 analyses of various
portions of 25 species taken from various locations.
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4. Results of Reassessment and Recommendations
%
The Toxicology and Chemistry Branches have rereviewed all data on
which the original action level recommendations were made and have also
taken into consideration data received since those recommendations were
forwarded. The latter include additional residue data and an NCI Chlordecone
Carcinogenesis Bioassay report. The review confirms the original action
level recommendations, 0.1 oom finfish, 0.3 ppm shellfish, 0.4 pptn crab.
The toxicological review was "calculated on the original basis of a
1000-fold safety factor applied to the rat chronic feeding study data.
Some minor variations from the original were seen in the Toxicology Branch
calculations due to the use of more recently developed dietary intake
figures in the calculations. Because of the demonstrated carcinogenic
potential of Kepone in two species of test animals, the lack of a clear
cut "no-effect level" in the two year rat feeding study, and the evidence
that Kepone is a cumulative toxin, no recommendation is made to revise" trie
established Kepone action levels at the present time.
The major recommendation change from the Chemistry Branch Review, in
light of additional experience with the analytical method, is to adopt
0.05 ppm (as opposed to 0.02 ppm) as the baseline enforcement action level .
subject to modification by toxicological or benefit/risk parameters.
Acceptance of 0.02 ppm would require extremely careful control on the
analytical method.
As part of the evaluation of current action levels, an independent
study of risks and benefits was performed by scientists in the Office of
Special Pesticide Reviews (attached). Emphasis was placed on the identi-
fication, articulation and measurement of variables, either health or
economic related, which are affected by alternative regulatory options.
Specifically, the paper presents an analysis of the human health impacts
which might be associated with maximum Kepone exposure (residues equaling.
the current action levels) from Chesapeake Bay finfish, shellfish and
blue crabs. Health impacts were evaluated using two currently accepted
models for cancer assessment—the "one-hit model" and the "log-probit
model.-under several alternative patterns of human seafood consumption.
In an attempt to tie a measure of benefit to the seafood sector affected
by Kepone action levels, the study also examined the total protein pro-
duction for human consumption arising from Chesapeake Bay fisheries as
well as other economic characteristics. The information contained in the
Office of Special Pesticide Review's study will be used as input into
the decision process regarding recommendations for Kepone action levels.
(3.
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Attachment A
Sunnary And Analysis Gf The Currently
Available Kepons Residue Data
Introduction
Samples of Fin Fish and Shell Fish from the Virginia and Maryland
Maters of the Chesapeake Bay and its Tributary Rivers have been collected
1n several major sampling programs conducted by the States Maryland and
Virginia and the Food and Drug.Administration and tha Environmental
Protection Aqency. To our knowledge no cor&plete summary of all the Kepone
Residue analysis from these program is availably yet. However, the analy-
tical results from over fiOO samples collected in these programs were pro-
vided to us by Or, Paul Corneliussen of FDA and Dr. Jack Blanchard of EPA.
Of these samples adequate information concerning snecies, collection point
and how the sample was prepared for analysis was available for 470 of these
samples. These 47Q samples represented about 25 different snecies of marine
life. A discussion of these residue data are presented here.
Samples collected from the James River (up-stream from the Janes River
Bridge) were considered separately from the Chesapeake Bay (including the
Hampton Roads area). This was done because of the hich levels found in the
Oarms River samples and because the State of Virqinia has banned .fishing in the
Jar^es Rivor. Consideration of data was further divided into fin fish; clams,
oysters conch and muscles-, and crabs, because it is on these commodities that
the current action levels haw been established.
In general the data for these samples showed markedly non-normal dis-
tribution such that approximately 702 of the reported values are below their
respective arithmetic means. The third moments about the mean (a measure
of skewnsss: it equals 0 for a normal curve and less than 0.5 for approxi-
mately random distributions) ranged from 4 to 5 for raost of tho distributions.
Because of tho non-nornal distribution of' these data the statical inferences
that can be drawn are limited. However, the conclusions that can be drawn
are discussed below.
F1n_£1sh
Chesapeake Bay: Residue data and adequate background information for
193 samples representing 16 species of fin fish taken front the Chesapeake
and its tributary rivers (except the James) were available. With the pos-
sible exception of shad no significant difference between species was detected.
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Excluding the shad, the residue levels reported ranged from 0 to 0.86 ppro
and averaged 0.056 ppm with a standard deviation of 0.114 pom. The shad
averaged 0.117 ppm with a standard deviation of 0.223 ppm. However, be-
cause of the non-normal distribution of the data no definitive conclusion
can be reached as to whether this difference is significant. (See Con-
culsion below). 156 or 3035 of the reported values were below the mean.
Only 8* of the samples collected exceeded the current n.l pptn action level.
Approximately 5% exceeded the 0.2 ppm level. Mo definitive conclusion as
to what percentage of fish caught in the Bay would be expected to exceed
the 0.1 ppm level can be made. However, these data appear to indicate that
about 8-10% of the fish caught may be over the current action level.
James River: Residue data and adequate background information for 51
samples representing 10 species of F1n F1sh taken from the James River were
available. Residue levels reported ranged from 0 to 3.1 ppra. The average
value for all James River F1n Fish was .931 ppm with a standard deviation of
1.85 ppm. Again almost 702 of the reported values were below the mean. 55%
>f all sample exceeded the current 0.1 ppm action level, and approximately
1/3 of the samples exceeded the 1 ppm level. The residua levels reported
for the 25 shad samples taken from the'James River were no higher than other
species, in fact their average residue level was only 0.503 ppm. The data
:end to indicate that the average residue level in F1n Fish taken from the
James River would approach 1.0 ppm.
Hams, Oysters. Conch, and Mussels
Chesapeake Day: Residue data for 110 sanples of these shell fish taken
rom the bay were considered. Residue levels reported ranged from 0 to 0.76
pm. The average value was 0.046 ppm with a standard deviation of 0.111 ppm.
gain the distribution of residue values was badly skewed with 742J of all
eported values below the mean. Only 2 samples or about 2% bore residues
bove the current 0.3 ppm action level. The data appear to indicate that
esldue levels 1n these shell fish taken from the Bay are comparable to the
evels in Fin Fish.
Janrss River: Residue data for 55 samples of these shell fish taken from
le James River are available. The reported residue levels ranged from 0 to
.51 ppm. The average residue level was 0.209 ppm with a standard deviation
' 0.12S ppm. 222 of these samples exceeded the current 0.3 ppm action level.
je data tend to indicate that the levels 1n this class of shell fish taken
*om the James River will be less than the corresponding levels in Fin Fish.
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Irabs
Chesapeake Rls can be drawn.
Additional Kepow» residue samples wore collected by the Food and Drug
Administration.from the waters of the Atlantic Ocean and the Gulf of Mexico.
The residue data frcsi the analyses of these samples arc also available. How-
ever these data w»re not Included 1n this evaluation, because of tha rwch
lower exposure of those samples to Kepone residues.
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.Vabs
Chesapeake Bay: Residue data and adequate background information arc
vallable for 48 sairples of crabs. The edible portions of both hard and soft ,
rrabs were included. The soft crab data was included in these data because
jf the limited number of samples available. The reported reside values ranged
from 0 to 3.44 ppn. The residues averaged .261 pp?n with a standard deviation
jf 0.551 ppm. Again alrcost 70S of the reported values wer« below the wean.
however. 12?J of samples were abova the current 0.4 ppni action level and 732.
were above the 0.5 ppm level* These data tend to indicate that average resi-
due levels in crab neat from crabs taken from the bay will approach 0.3 ppn
and that about 20% of the crabs piny exceed the current action level.
James River: Only five samples of crabs taken froro tha Jaises River are
available. Residue values ranged froro 2.C4 to 3.10 ppro and averaged 2.59 ppm.
In conclusion the data demonstrate a markedly non-normal distribution;
*hust indicating that there were additional pararncters effecting the Kapone
residue levels in fish than wera included in our analysis. The first para-
BWter considered was geographical location, but further dividing of the data
into smaller areas for consideration provided little iraproveswnt in the dis-
tribution of residues. Because Kepone is a persistent compound the length
of time a specimen is exposed (generally its age) would be expected to be en
important factor. However, Information as to age or even weight of samples
was only available for a portion of the data, and thus could not be included
in our considerations. Also the season of the year a sample was taken in
sons species could significantly effect the resulting residue levels.
Thus, the data indicate that the inferences that can be dravm front these
data are vsry limited because it can not ba demonstrated that the undefined
parameters effecting the distribution of residues will be consant for any
subsequent samplings. Perhaps, when a complete sugary of all the samples
collected in the various state and federal sampling programs is available a
better delineation of parameters i?ffecting,residue levels will be possible,
and icore definitive predictions regarding residue levnls can be dravm.
Additional Kepont* residue samples were collected by the Food and Drug
Administration, from the waters of the Atlantic Ocean and the Gulf of Mexico.
The residue data from the analyses of these samples arc also available. How-
ever these data w«ro not Included in this evaluation, because of the nuch
lower exposure of tlmse samples to Kepone residues.
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