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

14
Table 6. Mean wet-weight and lipid-weights residues (whole fish) based on 102 stations (1976-79) and 78 stations
(1974-79). Within each set of two columns for 1976-79 and three columns for 1974-79, means in italics are not
significantly different. See text for description of transformations used.
Wet-weight means Lipid-weight means
1976-79 1974-79 1976-79 1974-79
1976-77 1978-79 1974 1976-77 1978-79
1976-77 1978-79 1974 1976-77 1978-79
DDT Homologs
p,p'-DDE 0.28 0.26 0.41 0.27 0.26 3.01 3.08 4.52 3.09 3.09
p,p'-DDD 0.09 0.09 0.15 0.09 0.10 1.04 1.08 1.38 1.08 1.14
p,p'-DDT 0.06 0.04 0.06 0.05 0.04 0.49 0.40 0.40 0.50 0.41
EDDTb 0.40 0.37 0.57 0.38 0.37 4.34 4.46 6.39 4.46 4.53
PCB's
Aroclor 1248 0.14 0.14 - - - 0.58 0.74 - - -
Aroclor 1254 0.47 0.47 0.96 0.53 0.50 4.07 4.99 7.84 4.95 5.40
Aroclor 1260 0.37 0.38 0.06 0.39 0.41 3.34 3.68 0.29 3.92 4.39
EPCBc 0.87 0.86 1.09 0.97 0.97 8.00 9.56 10.52 9.71 11.03
Others
Toxaphene 0.37 0.33 0.16 0.38 0.32 2.02 1.94 0.47 2.19 2.03
HCB 0.01 <0.01 - - - 0.09 0.03 -
a-BHC 0.02 <0.01 - - - 0.27 0.05 - - -
,y-BHC 0.01 <0.01 - - - 0.06 0.01 - - -
Dieldrind 0.06 0.05 0.09 0.06 0.06 0.51 0.44 0.67 0.59 0.59
Endrin 0,01 <0.01 <0.01 0.01 <0.01 0.10 0.03 0.01 0.12 0.04
Heptachlore 0,04 0.02 <0.01 0.01 0.03 0.11 0.19 <0.01 0.12 0.22
cis-Chlordane 0,06 0.07 - - - 0.61 0.71 - - -
tram-Chlor-
dane 0.03 0.03 - - - 0.28 0.26 -
cis-Nonachlor 0.01 0.03 - 0.12 0.34 - - -
trans-Nona-
chlor 0.03 0.05 0.29 0.57 - - -
ePercent lipid, 1976-79: 1 976-77, 6.7 1; and 1978- 79, 6.24. Percent lipid, 1974-79: 1974, 6.08; 1976-77, 6.41; and 1978-79, 6.12.
Within each combination of years, these means were not significantly different.
bp,p'-homologs.
eAroclors 1254 an d 1260 for 1974; and 1248, 1254, and 1260 for 1976-79,
dIncludes aldrin for 1976-77.
eIncludes heptach lor epoxide.
lipid weight reported for the period 1970-74. This decline
in the annual total DDT maxima was reflected in corre-
sponding decreases for all three p,p'-homologs (DDE,
DDD, and DDT), Our ANOVA showed that differences
in mean residues of the DDT homologs between 1976-77
and 1978-79 were not significant (Tables 5 and 6). Both
lipid-weight and wet-weight residues for the period 1976-79
averaged significantly lower than corresponding values for
1974 for total DDT and for all p,p'-homologs except
p,p'-DDT (Tables 5 and 6). However, p,p'-DDT residues
in years after 1972 were approaching the limits of detec-
tion. Consequently, there were no significant time-period
differences for p,p'-DDT. The homolog DDE represented
70% of the total p,p'-DDT homologs for both 1976-77 and
1978-79 (Fig. 3) - a percentage that was unchanged from
1974 (Schmitt et al. 1981). Before 1974, a steady increase
in the relative amount of DDE accompanied an overall
decline in total DDT residues.
1.2
DDT
1'0 DDD
w 0.8 DDE
?y
0.6 EtCC9 P'P'- homolog
0
7/7
0.4
0
0Us/ 757 01'
.2 m
0
u o.a
1969 1970 1971 1972 1973 1974 1976-77 1978-79
Year
Fig. 3. Contributions of three p,p'-DDT homologs to total
p,p'-DDT, 1969-79.
Analysis of covariance revealed that most of the 78 sta-
tions with continuous data since 1974 showed unchanging