Effects of pulse exposure to sublethal levels of hydrogen cyanide on reproduction of American flagfish.

American flagfish (Jordanella floridae) were exposed to intermittent cyanide concentrations ranging from 0.065 to 0.15 mg/L hydrogen cyanide to determine the effects upon the embryonic, juvenile, and adult stages of development along with hatching success and fry survival of the subsequent F1 generation. The most significant effect was observed following embryonic exposure to levels as low as 0.075 mg/L hydrogen cyanide from fertilization to hatching. Hatching success was reduced to 37% when compared with controls while egg production among those embryos which successfully completed hatching and reached sexual maturity was subsequently reduced by 30%. A 5-day exposure to levels as low as 0.065 mg/L during the embryonic and juvenile stage produced a 40% reduction in egg production at sexual maturity and a further 33% reduction in the hatching success of the F1 generation. Exposure during the embryonic and adult stage produced a 27% reduction in fecundity. The results also suggest that exposure during embryonic development is responsible for the identical but shortened estrous cycle and delayed sexual maturity observed following embryonic (Group A), embryonic and juvenile (Group B) and embryonic and adult (Group C) exposure to hydrogen cyanide.