r/EPA
United States
Environmental Protection
Agency
Great Lakes National
Program Office
536 South Clark Street
Chicago, Illinois 60605
EPA-905/3-85-001
March, 1985
Contaminant Trends
In Lake Trout
(Salvelinus namaycush)
From the Upper
Great Lakes
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-------
EPA 905/3-85-001
and
GLFL no. 639
CONTAMINANT TRENDS
IN
LAKE TROUT (Salveilnus namaycush)
OF THE
UPPER GREAT LAKES
David S. DeVault
U.S. Environmental Protection Agency
Great Lakes National Program Office
Wayne A. Willford and Robert J. Hesselberg
U.S. Fish and Wildlife Service
Great Lakes Fishery Laboratory
1451 Green Road
Ann Arbor, Michigan 48105
For
U.S. Environmental Protection Agency
Great Lakes National Program Office
536 South Clark Street
Chicago, Illinois 60605
-------
DISCLAIMER
"This report has completed the EPA peer and publications review process
and is approved for publication as an EPA document. Mention of trade
names or commercial products does not constitute endorsement or recom-
mendation by EPA."
-------
FOREWORD
The Great Lakes National Program Office (GLNPO) of the U.S. Environmental
Protection Agency was established in Region V, Chicago to focus attention
on the significant and complex natural resource represented by the Great
Lakes.
GLNPO implements a multi-media environmental management program drawing on
a wide range of expertise represented by universitites, private firms, State,
Federal and Canadian governmental agencies and the International Joint Com-
mission. The goal of the GLNPO program is to develop programs, practices
and technology necessary for a better understanding of the Great Lakes
system and to eliminate or reduce to the maximum extent practicable the
discharge of pollutants into the Great Lakes system. The GLNPO also
coordinates U.S. actions in fulfillment of the Agreement between Canada
and the United States of America on Great Lakes Water Quality of 1978.
This study was carried out under a Cooperative Agreement with U.S. Fish
and Wildlife Service, Great Lakes Fishery Laboratory, Ann Arbor, Michigan.
ii
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ABSTRACT
Contaminant body burdens in lake trout from the Upper Great Lakes have been
monitored since 1970 on Lake Michigan and since 1977 and 1978 on Lakes
Superior and Huron by USEPA, Great Lakes National Program Office and
USFWS, Great Lakes Fishery Laboratory.
Analysis of the Lake Michigan data shows that mean PCB concentrations de-
clined from a maximum of 22.91 mg/kg in 1974 to 5.63 in 1982. Mean total
DDT concentrations declined from 19.19 mg/kg in 1970 to 2.74 mg/kg in 1982.
The decline in both contaminants closely followed first order loss kinetics.
If the current declines continue, PCB concentrations will decline to the
USFDA tolerance of 2.0 mg/kg in 1988. Mean total DDT concentrations
will fall to the IJC objective of 1.0 mg/kg by 1991. Mean dieldrin con-
centrations increased significantly from 0.20 mg/kg in 1971 to 0.58 mg/kg
in 1979 before declining to 0.21 mg/kg in 1982. The decline from 1979-
1982 followed first order loss kinetics. As this decline is not reflected
in other species (bloater chubs, smelt) it will require additional years of
monitoring to determine if the decline in dieldrin concentrations between
1979 and 1982 truly represents a declining trend.
Contaminants in lake trout from Lake Superior and Lake Huron generally de-
clined over the study period. The only statistically significant trend
other than in Lake Michigan was for total DDT which declined significantly
in Lake Superior lake trout. Large data variance and the short time frame
covered (1977-1982) interfered with detection of trends on Lakes Superior
and Huron.
111
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CONTENTS
Foreword i i
Abstract , iii
Tables and Figures v
Introduction .1
Methods 2
Results 8
Discussion and Conclusions 19
References 21
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Table and Figures
Table 1 - Sample Collection Data 6
Table 2 - PCB and Pesticide Detection Limits 7
Table 3 - Mean Contaminant Concentrations in Lake Trout from
Lake Michigan 9
Table 4 - Mean Contaminant Concentrations in Lake Trout from
Lake Huron 16
Table 5 - Mean Contaminant Concentrations in Lake Trout from
Lake Superior 17
Figures
Figure 1 - Lake Trout Collection Sites 3
Figure 2 - PCB Concentrations in Lake Michigan Lake Trout 11
Figure 3 - Total DDT Concentrations in Lake Michigan Lake Trout 12
Figure 4 - Dieldrin Concentrations in Lake Michigan Lake Trout.... 13
Figure 5 - Oxychlordane Concentrations in Lake Michigan Lake Trout.........14
Figure 6 - Total DDT Concentrations in Lake Superior Lake Trout 18
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INTRODUCTION
The presence of toxic organic contaminants, many of which bioaccumulate in
fish, is one of the most serious environmental problems in the Great Lakes.
During the past decade, contaminants such as PCB, DDT and dieldrin have
been found in Great Lakes fish at concentrations exceeding U.S. Food and
Drug Administration action levels. Bans and restrictions on the use of
these compounds have been implemented in an effort to control these problems.
In response to its responsibilities under the U.S. and Canadian Great Lakes
Water Quality Agreements of 1972 and 1978, the International Joint Commission
(IJC) has assisted in the development and implementation of a coordinated
surveillance and monitoring program "to assess compliance with pollution
control requirements and achievement of objectives, to provide information
for measuring loads and whole lake response to control measures, and to
identify emerging problems." As part of the coordinated surveillance
program, the U.S. Environmental Protection Agency's, Great Lakes National
Program Office (GLNPO) and U.S. Fish and Wildlife Service (USFWS), Great
Lakes Fishery Laboratory have cooperated in a program to monitor contami-
nant trends in fish collected from each of the Great Lakes and Lake St. Clair,
In this first report resulting from the Cooperative Program we present
the results of the analysis of lake trout (_Sa_1l_ve_1Li.nu.% namaycusn) collected
in Lakes Michigan, Superior, and Huron in 1977-1982.
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METHODS
Lake Trout were collected by gillnet from Lakes Michigan, Huron, and Superior
(Figure 1) in the fall of the year by USFWS personnel. The fish (60 per
collection site) were put into plastic bags, frozen whole, and transported
to the USFWS, Great Lakes Fishery Laboratory in Ann Arbor, Michigan where
they were sorted into small (300-450 mm), medium (451-650 mm), and large
(>650 mm) size categories (20 fish per category) for each collection site and
year. Within each size category the fish were grouped into four composite
samples consisting of five fish each and homogenized in a Hobarf" vertical
chopper/ mixer. Subsamples of the homogenized tissue were weighed and stored
frozen at <-30°C in solvent-washed glass jars with foil -lined screw caps until
analyzed by the USEPA Central Regional Laboratory (CRL), Chicago, Illinois.
At CRL, the samples were thawed, dried with Na2S04, and lipids and contaminants
were column extracted with two 50-ml aliquots of 10% ethyl acetate in petroleum
ether (Hesse! berg and Johnson 1972). Lipids were separated from the extract by
gel permeation chromatography (Stalling e£ al_. 1972). Pesticides and PCB were
separated on a column of silica gel (Snyder and Reinert 1971). Final separation
and quantisation of pesticides and PCBs was by a Varian 3700 dual column gas
chromatograph with Ni63 electron capture detectors (CRL 1982) under the follow-
ing operating conditions:
Column A Column B
Column length 2.4mx2mm i.d. 2.4mx2mm i.d.
Column materials 4% SE-30/6% SP2401 on 3% OV-101 on Supelcoport
Supelcoport 100-120 mesh 80-100 mesh
Injection temperature 270°C 270°C
Oven temperature 200°C 200°C
Detector temperature 320°C 320°C
N2 carrier gas flow ca. 30 ml/min ca 30 ml/min
Range (amps/mv) lO"10 amp 10'10 amp
All results were computed on a mg/kg wet weight basis, and were not corrected
for extraction or recovery efficiency.
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Figure 1. Lake trout collection sites
3
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As initially designed, the sampling program was intended to compare contaminant
levels in fish, both temporally and spatially, in the three size categories
of fish collected from each location. The results were to be compared by
using analysis of covariance techniques. This approach requires that a signifi-
cant correlation exist between contaminant concentrations and the size of
fish. If differences are to be tested for, the regressions of contaminant levels
and fish size must also have similar slopes. The data for 1977-1979 from
Lakes Michigan, Huron, and Superior were initially analyzed by using this approach,
Since data for three years, 13 organic contaminants and three sites were included
in the analysis, 117 regressions between contaminant concentration and fish
size were possible. Of these, 63 were significant at the 95% confidence level.
Among the significant regressions, several exhibited significant (p<0.05)
differences in slopes, either between years or collection sites. Thus, less
than half of the available data met the requirements for the test. We there-
fore, decided that although the analysis of convariance technique may be
worthy of further evaluation, the use of mean statistics with specific size
ranges of fish was the most appropriate approach for analyzing available data
and determining differences in contaminant concentrations between sites and
within sites over time.
To achieve a comparable size range of fish from 1977 through 1981 and into future
years (current collections consist of fish 600-700 mm long) we used the following
procedure. The mean length of all medium and large size group composite samples
from each site and year was calculated. When this mean was below 620 mm or
above 640 mm, the composite sample with the smallest or largest length was
dropped and the mean recalculated. This procedure was repeated until we arrived
at a mean length within the 620 mm to 640 mm range. The composite samples
-------
thus selected were then treated as environmental replicates and mean statistics
were used to compare contaminant concentrations. Table 1 presents the fish size
and lipid data for the samples thus developed.
For purposes of statistical analyses and graphical display, we calculated
concentrations of contaminants detected, hut below quantitation limits, as
1/2 of the limits given in Table 2.
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TABLE 1
SAMPLE COLLECTION DATA
Lake and Year
Length (mm)
Mean SE
Weight (g)
Mean SE
Lipid %
Mean SE
Lake Michigan*
Saugatuck
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
Lake Huron
Rockport
1977
1978
1979
1980
1981
1982
Lake Superior
Apostle Island
1977
1978
1979
1980
1981
1982
18
20
9
30
30
29
30
3
8
6
6
3
10
6
5
6
6
10
7
7
6
7
5
10
613 ( 9)
579 ( 8)
648 (15)
602 (10)
616 (10)
613 ( 8)
606 ( 9)
636 (53)
631 (27)
630 (40)
637 (18)
620 (37)
612 ( 4)
NO
637 (18)
640 (21)
633 (18)
628 (28)
623 ( 7)
640 (27)
638 (27)
630 (24)
636 (24)
634 (29)
619 ( 7)
2084 (149)
2314 (125)
2576 (178)
2353 (120)
2516 (130)
2581 -( 92)
2337 (103)
2888 (681)
2447 (311)
2844 (461)
2843 (296)
2646 (497)
2466 ( 47)
25.63 (1.69)
18.03 (0.68)
18.52 (1.81)
16.00 (0.70)
16.50 (0.56)
19.10 (0.55)
16.80 (0.49)
16.59 (0.88)
17.50 (0.76)
16.78 (1.10)
17.68 (0.74)
17.96 (0.88)
16.53 (0.33)
SAMPLE
2522 (210)
3017 (308)
2674 (230)
2775 (343)
2527 ( 84)
2927 (425)
3080 (400)
2797 (312)
2868 (360)
2762 (386)
2479 (103)
19.19 (0.65)
21.30 (0.78)
19.03 (1.10)
18.88 (0.64)
18.10 (0.71)
16.46 (1.80)
21.14 (1.20)
21.80 (1.80)
15.10 (1.30)
15.92
15.67
(0.93)
(0.43)
Data for 1970-76 from the U.S. Fish and Wildlife Service, Great Lakes Fishery
Laboratory, collected before the Cooperative Program began, and are based
on analyses of individual, whole fish.
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Table 2
PCB and Pesticide Detection Limits
Compound Quantisation
Limits mg/kg
o.p'-DDE 0.002
p.p'-DDE 0.002
o,p'-ODD 0.005
p.p'-DDD 0.005
o.p'-DDT 0.020
p.p'-DDT 0.002
Dieldrin 0.002
Total Aroclor (as 1254) 0.030 - 0.050
Heptachlor 0.001
Oxychlordane 0.005
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RESULTS
PCBs were the dominate contaminant at all sites reflecting its once wide spread
use (Durfee 1976), environmental persistance, and tendency to bioacumulate
(EPA 1983). The continued presence of DDT residues illustrates the duration
of contaminant problems long after measures to ban manufacture and use are
inacted. Lake Michigan lake trout generally contained the highest contaminant
concentrations and Lake Superior the lowest. Clark et al. (1984) found a
similar pattern in the relative contaminant levels in coho salmon. Studies
by Frank \et al. (1980) and Frank et al. (1981) found the sediment concen-
trations of PCB, chlordane plus heptachlor and DDT to be similar in Lake
Michigan and Huron and substantially lower in Lake Superior
La ke Mi chi^gan
Table 3 presents the annual means and 95 percent confidence intervals for
contaminants in lake trout off saugatuck, Michigan in 1970-19R2. Before
1977 individual fish were analyzed by the Great Lakes Fishery Laboratory
by the analytical methodology described in Willford et^ a\_. (1976). Since
1977 five fish composite samples were analyzed by USEPA.
Mean PCB concentrations (mg/kg) increased from 12.86 in 1972 to 22.91 in
1974, and the declined to 6.49 in 1981.
Mean PCB concentrations from 1974 - 1981 declined, generally following
first order loss rate kinetics in the form of the following equation:
Ct =C0e'*T (1)
where C^ = concentration at time, Cg = initial concentration, K = rate
constant, and T = Time
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Table 3. Mean Contaminant Concentrations in lake trout from
Lake Michigan off Saugatuck, mg/kq wet weight
(95% confidence intervals in parenthesis)
Year
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
Wfl ^ IMnt
PCB*
NA
NA
12.86
( 8.11,
18.93
(16.85,
22.91
(19.18,
22.28
(19.38,
18.68
(16.02,
11.58
(-2.30,
8.18
( 5.50,
8.82
( 5.20,
9.93
( 2.00,
6.49
( 4.51,
5.63
( 5.36,
Anal V7pd
17.61)
21.01)
26.64)
25.18)
21,34)
25.4 )
10.90)
12.50)
17.80)
8.46)
5.89)
DDT
19.19
(15.90,
13.00
(11.24,
11.31
( 8.05,
9.96
( 8.60,
8.42
( 6.68,
7.50
( 6.25,
5.65
( 4.61,
6.34
(-0.40,
4.58
( 2.32,
6.91
( 2.80,
4.74
( 1.90,
3.22
( 2.11,
2.74
( 2.34,
22.46)
14.76)
14.57)
11.32)
10.16)
8.75)
6.69)
13.10)
6.83)
11.00)
7.50)
4.34)
3.14)
Oxychlordane
NA
NA
NA
NA
NA
NA
NA
0.230
(-0.71, 0.531)
0.175
( 0.072, 0.278)
0.240
( 0.136, 0.344)
0.160
( 0.039, 0.280)
0.061
( 0.049, 0.073)
0.075
( 0.057, 0.093)
Dieldrin
0.27
(0.22,
0.20
(0.17,
0.20
(0.14,
0.27
(0.24,
0.30
(0.27,
0.35
(0.32,
0.30
(0.28,
0.40
(0.35,
0.44
(0.28,
0.58
(0.25,
0.335
(0.20,
0.26
(0.24,
0.21
(0.16,
0.32)
0.23)
0.26)
0.30)
0.33)
0.38)
0.32)
0.45)
0.61)
0.91)
0.47)
0.28)
0.28)
Number of
Samples
18
20
9
30
30
29
30
3
8
6
6
3
10
._.- — !„„ „•„ 1Q77 ri
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Figure 2 illustrates the loss trajectory based on the least squares fit (r2 =
89.6, P<0.01) to the mean yearly PCB concentrations. The rate constant is
-0.18/yr.
Mean total DDT concentrations (mg/kg) declined from 19.19 in 1970 to 2.74
in 1982. The observed decline in mean total DDT concentrations also followed
first order loss rate kinetics (equation 1). Figure 3 illustrates the loss
trajectory from 1970 to 1982. The rate constant is -0.13/yr with r2 = 90.9
Mean dieldrin concentrations (mg/kg) decreased from 0.27 in 1970 to 0.20
in 1971, then increased to 0.58 in 1979 after which concentrations declined
to 0.22 in 1982. The increase in mean concentrations between 1972 and
1979 was highly significant (P<0.01, R2 = 86.6) following the linear equation:
Ct = 0.045 (Y) - 3.02 (2)
Where C^ = mean dieldrin concentration (mg/kg) in year t and Y = year
(1900's) from 72-79
From 1979 to 1982 mean concentrations declined, following first order loss
kinetics (equation 1), with a loss rate of -0.32/yr. The curve on Figure 4
illustrates the loss trajectory based on a least squares fit to the data
(r2 = 93.2, P<0.05).
The chlordane metabolite, oxychlordane, increased from 1977 through 1979
and decreased from 1979 through 1982. The decrease (Figure 5) in mean
concentration from 1979 to 1982 was significant (P<0.05, R2 = 85.1) following
the 1 inear equation.
Ct = 0.059 (y) + 4.92 (3)
Where C^ = mean oxychlordane concentration (mg/kg) in year t and y = year
(1900's) from 79 to 82.
10
-------
30 r
28 -
26
24
22
20
18
D)
— 14
CD
o
a
12
10
8
6
„
I
-23
I
I
I
1972
1974
1976 1978
YEAR
1980
1982
Figure 2. PCB Trends in Lake Michigan Lake Trout
11
-------
1970
1972
1974
1976
YEAR
1978
1980
1982
Figure 3. Total DDT trends in Lake Michigan lake trout.
12
-------
a>
1 00 -
095 -
0.90 -
0.85
0.80
075
0.70
0.65
0.60
n
0 55
0.50
2
"e
6 0.45
0.40
0.35
0.30
0.25
0.20
0.15
0 10
005
0.00
-
I
1970
1972
1974
1976
YEAR
1978
1980
1982
Figure A. Dieldrin trends in Lake Michigan lake trout.
13
-------
.54
.50
.46
.40
.36
O)
-0
.32
O)
~ .28
0)
c
CO
I-24
JC
O
X* .20
O
.16
.12 -
.08
.04
••
0.0 -
-.071
I
"
1
1
1
1977
1978
1979 1980
YEAR
1981
1982
Figure 5. Oxychlordane trends in Lake Michigan lake trout.
14
-------
j-a_ke_Jju.rgjl_
Unlike Lake Michigan, where comparable trend monitoring begain as early as
1970, the Lake Huron data base began in 1978 (Table 4). Despite general
declines in the mean concentrations of PCB and DDT from 1979 to 1982 no
statistically significant (P<0.05) trends were observed for any of the
monitored compounds. Annual mean total DDT and PCB concentrations exceeded
the IJC (1978) objectives (1.0 mg/kg and 0.1 mg/kg, respectively) in each
year of the study.
Lake Super101r
Contaminant concentrations in Lake Superior lake trout are given in Table 5.
The relatively low levels of PCB, dieldrin, and oxychlordane did not exhibit
trends nor statistically significant (P<0.05) differences over the study
period.
Total DDT concentrations in Lake Superior lake trout (Figure 6) declined
significantly (P<0.05, r2 = 78.9) from 1977 to 1982, following the equation:
Ct = -0.162 (y) + 13.7 (4)
Where C^ = mean total DDT concentration (mg/kg) in year t and y = year (1900s)
from 77 to 82.
The annual mean PCB concentration exceeded the IJC (1978) objective in each
year of the study. The IJC (1978) total DDT objective was exceeded by the
mean concentrations in 1977 through 1979, but not from 1980 to 1982.
15
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Table 4
Results of Contaminant Monitoring of Lake Trout
From Rockport, Lake Huron
Mean (95% Confidence Interval)
All data mg/kg wet weight
Year
1978
1979
1980
1981
1982
PCB*
2.92
(2.32,
3.66
(1.57,
3.44
(2.46,
3.51
(2.31,
2.10
(1.72,
3.52)
5.75)
4.42)
4.72)
2.49)
DDT
2.19
(2.05,
2.85
(1.94,
1.53
(1.10,
1.79
(1.15,
1.31
(1.13,
Oxychlordane
2.33)
3.76)
1.96)
2.43)
1.49)
0.038
(0.033,
0.060
(0.024,
0.056
(0.039,
0.058
(0.040,
0.059
(0.044,
0.043)
0.097)
0.073)
0.076)
0.074)
Dieldrin
0.16
(0.14,
0.19
(0.14,
0.13
(0.10,
0.14
(0.12,
0.15
(0.11,
0.17)
0.24)
0.15)
0.16)
0.18)
Number of
Samples
6
5
6
6
10
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Table 5
Results of Contaminant Monitoring of Lake Trout
From the Apostle Island, Lake Superior
Mean (95% Confidence Interval)
All Data mg/kg Wet Weight
Year
1977
1978
1979
1980
1981
1982
PCB*
1.87
(0.95,
0.93
(0.65,
0.88
(0.59,
1.89
(0.41,
1.40
(0.37,
0.48
(0.36,
2.80)
1.21)
1.17)
3.36)
2.44)
0.60)
DDT
1.2
(0.76,
1.02
(0.66,
1.095
(0.61,
0.62
(0.13,
0.81
(-0.09,
0.288
(0.214
Oxychlordane
1
1
1
1
1
,0
.80)
.39)
.57)
.11)
• 71)
.47)
0.120
(0.059,
0.402
(0.110,
0.136
(0.102,
0.026
(0.018,
0.056
(0.001,
0.041
(0.036,
0.180)
0.700)
0.375)
0.035)
0.111)
0.047)
Dieldrin
0.05
(0.03,
0.06
(0.05,
0.07
(0.05,
0.045
(0.02,
0.05
(0.03,
0.05
(0.04,
0
0
0
0
0
0
.06)
.07)
.08)
.06)
.07)
.05)
Number of
Samples
7
7
6
7
5
10
*PCB quantitated as Aroclor 1254
-------
20 r-
1.8
1.6
1.4
1.2
e>
1 1.0
O
O
0.6
0.4
0.2
I
I
1977
1978
1979 1980
YEAR
1981
1982
Figure 6. Total DDT trends in Lake Superior lake trout.
18
-------
Discussion and Conclusions
Of the data sets for the three upper lake monitoring sites reported here,
only that for Lake Michigan, was sufficient to allow rigorous statistical
evaluation of trends with time. This is principally because FWS had collected
data for 6 years before the current U.S. EPA/U.S. FWS cooperative program was
begun in 1977. As a result of these extra years of data, we were able to
demonstrate that mean PCB and mean total DDT concentrations in lake trout off
Saugatuk declined in a manner that approximated first order loss kinetics.
Rodgers and Swain (1983) reported that the decline of PCB concentrations in
bloaters (Coregonus hoyi) from Lake Michigan (off Saugatuck) from 1972 to
1980 also approximated first order loss kinetics with a rate constant of
-0.12/yr. They used the trend data for bloaters to hindcast loads and then
used their loading estimates to forecast concentrations in other fish species.
They estimated that PCB concentrations in Lake Michigan trout would reach 2
mg/kg in 1987. By solving equation (1) for t, we calculate that PCB concen-
trations will drop to 2 mg/kg in 1988. This estimate is in excellent agreement
with the projections of Rodgers and Swain (1983), particularly when the
difference in approach and the uncertainties of such projections are considered,
These projections presuppose that PCB loading into Lake Michigan will continue
to decrease at a rate at least equal to that before 1982. As atmospheric
deposition now contributes will over 50 percent of the total load (Murphy and
Rzesutko 1977), this decrease may not be affected.
A similar projection of total DDT concentration suggests that mean con-
centrations will reach the IJC objective of 1.0 mg/kg in about 1991.
19
-------
Despite cancellation of most uses of aldrin and dieldrin in 1974 (EPA 1980),
mean concentrations in lake trout in Lake Michigan off Saugatuck increased
from 0.27 mg/kq in 1970 to 0.58 mg/kg in 1979. From 1979 to 1982 mean
dieldrin concentrations declined in a manner approximating first order loss
kinetics. However, other species such as bloater chubs and rainbow smelt
have not exhibited the decline observed in lake trout. Dieldrin concentrations
in bloaters in Lake Michigan increased from a mean of 0.27 (mg/kg) in 1970
to 0.43 in 1982 (Willford 1982), while rainbow smelt remained relatively
constant (range 0.046 - 0.071 mg/kg) from 1977 to 1982 (GLNPO-unpublished data).
Elevated dieldrin concentrations resulted in seizure of commerical catches of
Lake Michigan bloaters by the U.S. Food and Drug Administration in 1984
(David Crockett, U.S. Food and Drug Administration, Chicago, Illinois,
personal communications, 1984). Therefore, while the apparent decline in
lake trout is encouraging, it will require additional years of monitoring
to test this trend.
With the exception of DDT which declined significantly in Lake Superior lake
trout from 1977 to 1982, no significant changes in contaminant concentrations
were observed in lake trout from Lake Huron or Lake Superior. The combination
of limited data sets, large data variance, and relatively lower contaminant
concentrations interfered with the detection of trends. The ineffectiveness
of the study design used from 1977 to 1981 (sampling three size ranges of
fish), and the resulting requirements to select fish over a large size range
and greatly reduce the number of yearly samples, was partly responsible for
the large variance associated with the 1977 to 1981 data. Although the
covariance approach will be further evaluated, the monitoring protocol
used since 1982 for this cooperative program utilizes mean statistics
on results from 10 composite samples of 5 fish each, all of which are 600
to 700 mm long. The reduced variance under this more stringent sampling
protocol will greatly enhance the likelyhood of detecting significant differences
between any two sites or years when contaminant concentrations are changing.
20
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References
Clark, J.R., D.DeVault, R.J. Bowden, and J.A. Weishaar. 1984. Contaminant
"analysis of fillets from Great Lakes coho salmon, 1980.
J. Great Lakes Res. 10:38-47.
Central Regional Laboratory (CRL). 1982. Standard operating procedure for
the analysis of contaminants in fish for the open lake program Great Lakes
fish contaminant dynamics project. USEPA. Chicago, Illinois.
DeVault, D.S., and J.A. .Weishaar. 1984. Contaminant analysis of 1982 fall
run coho salmon. U.S. Environmental Protection Agency, Great Lakes
National Program Office. EPA 905/3-84-004.
Durfee, R.L. 1976. Production and usage of PCBs in the United States. In:
Proceedings of the National Conference on Polychlorinated Biphenyls.
U.S. Environmental Protection Agency, Office of Toxic Substances,
Washington,D.C. pp 103-107, EPA-560/6-75-004.
EPA. 1980. Ambient water quality criteria for dieldrin. U.S. Environ-
mental Protection Agency, Office of Water Regulations and Standards,
Washington, D.C. EPA 440/5-80-019.
EPA. 1983. Environmental transport and transformation of polychlorinated
biphenyls. U.S. Environmental Protection Agency, Office of Pesticides
and Toxic Substances, Washington, D.C. EPA 560/5-83-025.
Frank R., R.L. Thomas, H.E. Braun, J.Rasper, and R. Dawson. 1980. Organo-
chlorine insectides and PCB in surficial sediments of Lake Superior
(1973). J. Great Lakes Res. 6:113-120.
Frank R., R.L. Thomas, H.E. Braun, D.L. Gross and T.T. Davies. 1981.
Organochlorine insecticides and PCB in surficial sediments of Lake
Michigan (1975). J. Great Lakes Res. 7:42-50.
Hesselberg R.J., and J.L. Johnson. 1972. Column extraction of pesticides
from fish, fish food, and mud. Bull. Environ. Contam Toxicol.
7:115-120.
International Joint Commission. 1978. Status Report on persistent-toxic
pollutants in the Lake Ontario Basin. Great Lakes Water Quality Board,
Windsor, Ontario, Canada.
Murphy, T.J. and C.P. Rzeszutko. 1977. Precipitation inputs of PCBs to
Lake Michigan. J. Great Lakes Res. 3:305-312. *
Rodgers, P.W., and W.R. Swain. 1983. Analysis of polychlorinated biphenyl
(PCB) loading trends in Lake Michigan. J. Great Lakes Res. 9:548-558.
21
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Snyder, D. and R. Reinert. 1971. Rapid separation of polychlorinated biphenyls
from DDT and its analogues on silica gel. Bull. Environ. Contam. and T-oxicol
6:385-390.
Stalling, D.L., R.C. Tindle, and J.L. Johnson. 1972. Cleanup of pesticide and
polychlorinated biphenyl residues in fish extracts by gel permeation
chromatography J. Assoc. Off. Anal. Chen. 55:32-38.
Willford, A., J. Hesselberg, and W. Nicholson. 1976. Trends of polychlorinated
biphenyls in three Lake Michigan fishes. I^n: Proceedings of the National
Conference on Polychlorinated Biphenyls. U.S. Environmental Protection
Agency, Office of Toxic Substances, Washington, D.C. pp 177-181,
EPA-560/6-75-004.
Willford, A. 1982. Evaluating the presence and effects of contaminants in
fish of the Great Lakes. Minutes of the Great Lakes Fishery Commission
Annual Meeting, Green Bay, Wisconsin, June 9-10, 1982, Agenda Item 14.C.,
Appendix XXVI:273-284.
Zar, J. 1974. Biostatistical Analysis. Prentice Hall. Inc., Englewood
Cliffs, N.J.
22
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TECHNICAL REPORT DATA
(Please read fauructions on the reverse before completing)
1 REPORT NO.
EPA-905/3-85-001
3. RECIPIENT'S ACCESSIOWNO.
4. TITLE AND SUBTITLE
Contaminant Trends In Lake Trout
(Salvelinus namaycush) of the
Upper Great Lakes
5 REPORT DATE
April 1985
6. PERFORMING ORGANIZATION CODE
5GL
7. AUTHOR(S)
David S.
8. PERFORMING ORGANIZATION REPORT NO.
De Vault
9. PERFORMING ORGANIZATION NAME AND ADDRESS
U.S. Fish and Wildfile Service
Great Lakes Fishery Laboratory
1451 Green Road
Ann Arbor, Michigan 48105
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS
U.S. Environmental Protection Agency
Great Lakes National Program Office
536 South Clark Street, Room 958
Chicago, Illinois 60605
13. TYPE OF REPORT AND PERIOD COVERED
Fish Monitoring 1977-1982
14. SPONSORING AGENCY CODE
Great Lakes National Program
Office-USEPA. Region V
15. SUPPLEMENTARY NOTES
16. ABSTRACT
Contaminant body burdens in lake trout from the Upper Great Lakes have been
monitored since 1970 on Lake Michigan and since 1977 and 1978 on Lakes Superior
and Huron by USEPA, Great Lakes National Program Office and USFWS, Great
Lakes Fishery Laboratory.
Analysis of the Lake Michigan data shows that mean PCB concentrations declined
from maximum of 22.91 mg/kg in 1974 to 5.63 in 1982. Mean total DDT concentra-
tions declined from 19.19 mg/kg in 1970 to 2.74 mg/kg in 1982. The decline in
both contaminants closely followed first order loss kinetics. If the current
declines continue, PCB concentrations will decline to the USFDA tolerance of 2.0
mg/kg in 1988. Mean total DDT concentrations will fall to the IJC objective of
1.0 mg/kg by 1991. Mean dieldrin concentrations increased significantly from
0.20 mg/kg in 1971 to 0.58 mg/kg in 1979 before declining to 0.21 mg/kg in 1982.
The decline from 1979-1982 followed first order loss kinetics. As this decline
is not reflected in other species (bloater chubs, smelt) it will require additional
years of monitoring to determine if the decline in dieldrin concentrations between
1979 and 1982 truly represents a declining trend.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS C. COSATI Field/Group
Contaminants
Monitoring
Toxic organic
Pesticides
Lipids
Lake Trout
is. DISTRIBUTION STATEMENT Document is available
to the public through the National Techni-
cal Information Service, Springfield, VA
22151
19. SECURITY CLASS (ThisReport)
21. NO. OF PACES
20. SECURITY CLASS (Thispage)
22. PRICE
EPA Form 2220-1 (9-73)
GOVERNMENT PRINTING OFFICE: 1985-557-017
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