Effect of toxaphene on reproduction of fish.

The effect of Toxaphene on fish reproduction was investigated in sexually mature female zebrafish fed for two weeks with food contaminated with three different concentrations of the Pesticide (0.02, 0.23 and 2.2 micrograms/g fish/day). No overt differences were observed in reproductive success as assessed by examination of (a) total number of eggs spawned by each female, (b) percentage of fertilized eggs 24 hours after fertilization, (c) percentage of embryo mortality 72 hours after fertilization and (d) percentage of hatching 72 hours after fertilization. By contrast Toxaphene produced distinct effects of a dose response nature on oviposition. This observation is not only of interest with respect to Toxaphene, but also points to the importance of evaluating other pesticides for their effect on the oviposition of feral species that might be even more sensitive than zebrafish. Toxicity of Toxaphene was manifested both in the parent fish (skin discoloration, subcutaneous hemorrhages, particularly around the gill areas and backbones curved in the vertical plane) and in hatching embryos (half hatched).