7234

• UCREFRP Catalog Number: 7234
• Author: Kurey, W. J.
• Title: Organochlorine Contaminants in Fish of the Grand Valley ‎(Grand Junction Area of Colorado)‎.
• USFW Year: 1985.
• USFW - Doc Type: Grand Junction.
• Copyright Material: NO

1983 and 1984 attempts at sampling Reedwash at N Road failed to produce any
fish. There was nothing from that site with which to compare the 1982 high of
61.5 ppm toxaphene in viscera. None of the 1983 samples exceeded 1 opm.
Because 1 ppm is also the level of detection for toxaohene in the 1984
samples, and because the 1984 samples were whole fish and the 1983 samples
filets, comparison of data between years are of limited value.
If the ambient-level of toxaphene was constant, one would expect residues in
whole fish to fall between the higher levels in viscera and lower levels in
filets. The fact that 1984 whole fish residues of toxaphene are in or below
the range of values from 1983 filets (less than 1 ppm), one could expect that
the ambient toxaohene levels are the same or lower than 1983 levels.
The Colorado Department of Health analyzed 1984 composite filet samples from
Highline Reservoir (white crappie, 2 samples; largemouth bass, 2 samples;
channel catfish, 2 samples) and found no toxaphene at a level of detection of
0.1 ppm. They also found no toxaphene in the filet of a bluehead sucker taken
from the Colorado River at Skipper's Island near. Loma, Colorado.
The high toxaphene residue levels in fish from the Reed Wash area in 1982
could have resulted from some use of toxaphene in areas adjacent to Reed Wash
just below or, more probably, above the confluence with Peck and Beede Wash
(assuming fish residues were accurate reflections of local ambient concentra-
tions).. The lower toxaohene levels in fish from Peck and Beede (9.9 ppm) and
East Reed (6.4 ppm) Washes could have resulted from lower ambient levels or
from fish spending time in Reed Wash and then moving back to cleaner water.
In any event, the toxaphene source detected in 1982 appears to have been
transient. The uniformly low organochlorine levels and the apparent absence
of toxaphene in the 1984 samples are not indicative of any fishery contaminant
problem.
Summary
No toxaphene was detected in any of the fish from the Grand Valley of Colorado
(level of detection 1 ppm) in 1984. No other organochlorine pesticide
residues of significance were found.
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