7942

• UCREFRP Catalog Number: 7942
• Author: Schmitt, C. J., et al.
• Title: National Pesticide Monitoring Program
• USFW Year: 1983.
• USFW - Doc Type: Organochlorine Residues in Freshwater Fish, 1976-79.
• Copyright Material: NO

17
Table 7. Continued.
DDT homologs PCB's Other insecticides
Stationa p,p'-DDT p,p'-DDD p,p'-DDT EDDTb Aroclor 1254 EPCBc Dieldrind Toxaphene
80 0 0 + 0 0 0 0 -
81 0 0 0 0 0 0 0 +
83 0 0 0 0 - 0 - +
85 0 - - 0 - - 0 0
86 0 0 0 0 0 0 0 0
87 0 0 0 0 0 0 0 +
89 0 0 0 0 0 0 0 +
90 0 0 - 0 0 0 0 +
91 0 0 0 0 0 0 0 0
93 0 0 0 0 0 0 0 0
96 0 0 0 0 0 0 0 +
97 - - 0 - 0 0 0 0
98 0 0 0 0 0 0 0 0
99 0 0 0 0 0 + - 0
100 0 0 + 0 0 0 - 0
101 0 - 0 0 0 0 0 0
105 0 0 - - - 0 0 +
106 0 0 0 0 0 0 0 +
107 0 0 0 0 0 0 0 0
108 0 0 0 0 0 0 0 0
111 0 0 0 0 - - 0 0
113 + + 0 + 0 + 0 +
aSee Fig. 1 for locations of stations.
bHomologs of p,p'-DDT.
cAroclors 1254 and 1260 for 1974; 1248, 1254, and 1260 for 1976-79.
dIncludes aldrin for 1976-77.
cross-check analyses of the 1974 samples (Schmitt et al.
1981) suggests that the changes detected in mean residues
of Aroclors 1254 and 1260 between 1974 and 1978-79 were
artifacts of analysis. Most likely, the results for total PCB
best represent the national trend in PCB residues in fresh-
water fish: no significant change from 1974 through
1978-79.
Total PCB residues also changed little on a sta-
tion-by-station basis from 1974 (Schmitt et al. 1981) to
1978-79 (Table 7). Significant declines in lipid weight total
PCB residues occurred at stations 18, 39, 67, 85, and 111.
At all of these sites the residues exceeded 1.0µg/g wet weight
in 1974. Significant increases were restricted to stations
14, 29, 63, and 113. Aroclor 1254 residues declined signifi-
cantly at 14 stations, increasing only at stations 5, 8, 14,
and 44 (Table 7). At none of the four stations showing sig-
nificant increases did the residues exceed 1.5 µg/g wet
weight.
Because Aroclor 1248 residues were not measured in
1974, no station-by-station analysis of temporal trends could
be performed. However, the lower chlorinated components
present in Aroclor 1248 are less persistent in the environ-
ment than are the more highly chlorinated components that
dominate the Aroclor 1254 and 1260 mixtures. Therefore
the presence in fish of PCB's that resemble Aroclor 1248
may indicate the influx of "fresh," unweathered PCB's. Lab-
oratory studies have consistently shown that mixtures con-
taining these less-chlorinated components, like Aroclor
1248, are considerably more toxic to fish than are mixtures
composed predominantly of more highly chlorinated com-
ponents (Stalling et al. 1979). Significant Aroclor 1248 resi-
dues (? 1.0 µg/g wet weight) were found at stations 2, 3,
5, and 53 in the Northeast; stations 23, 24, 68, and 69 in
the Ohio River system; stations 83 and 89 in the Missouri
River system; station 72 in the Mississippi River at Wood-
man, Wisconsin; station 100 in Manoa Stream, Honolulu,
Hawaii; and at all of the active stations in Lakes Michi-
gan, Huron, St. Clair, and Ontario (17, 18, 20, 21, 1059
106, 107, and 109) except station 104 (Lake Michigan at
Beaver Island, Michigan).
Among the PCB residues examined, the station-year
interaction term in the overall ANOVA for 1976-79 (Ta-
ble 5) was significant only for Aroclor 1248. Significance
of this term implies that all the stations were not displaying
the same temporal trends (Schmitt 1981)-suggesting that
some stations were continuing to receive PCB residues con-
taining early eluting components, whereas most received
none, or only material that was weathered or that eluted
later.
The geographic distribution of stations with the highest
PCB residues did not change from that in 1970-74 (Schmitt
et al. 1981); concentrations still tended to be highest in the