Fate of hexachlorocyclopentadiene in water and goldfish

Fingerling goldfish were exposed to 4 and 5 ppb Hex in a renewable and a static system, respectively. In the former the rate of absorption was greater than the rate of elimination. Estimated momentary steady-state (SS) occurred at 8 days, the bioconcentration factor (KB) at steady-state was 1354 with a half-life (t1/2) of 14 days. In the static system SS reached in 2 days with a KB of 323 and t1/2 of 2 days, with the rate of uptake being greater than rate of clearance. Large goldfish were injected, i.p., with 40 μg of 14C-Hex and the radioactivity in water and tissues followed with time. In experiment 1 with water renewed every 4 days, 3 phases of elimination were detected with 50 and 95% clearance in 7 and 211 days, respectively. In experiment 2 without renewing the water, 2 phases of elimination were detected with 50 and 95% clearance in 9 and 107 days, respectively. Analyses of various tissues of goldfish 2, 4, 6, and 8 days following 14C-Hex injection showed 0.2 and 0.3 ppm equivalents, respectively, in gills and spinal cord. The residues in kidney and bile increased while those in other tissues, except liver, decreased with time. Pretreatment of fish with enzyme inhibitors or followed by exposing fish to Hex did not alter its toxicity indicating that biotransformation may not play an important role in Hex toxicity