Effects of Neutral Sulfite Semichemical Pulp Mill Effluent in the Mummichog (Fundulus heteroclitus.) Adult Fish Reproductive Test

Abstract

Short-term adult fish reproductive tests using freshwater species have demonstrated negative impacts on egg production in fish exposed to complex pulp and paper mill effluents. In an effort to address the ability of laboratory tests to predict effects on wild fish, mummichog (Fundulus heteroclitus) were exposed in saltwater conditions for 21 days to 3 and 30% final effluent of a neutral sulfite semichemical pulp mill that discharges into an estuarine environment in eastern Canada. Although no effects on gonad size, liver size, or condition factor were found, egg production was significantly increased by 31% and decreased by 30% when fish were exposed to 3 and 30% final effluent, respectively. This study i) is the first to demonstrate a decrease in egg production when fish are exposed to complex effluents under estuarine conditions and ii) provides the first linkage of effects on gonad size in wild fish to egg production from laboratory testing in the same species. In so doing, this study also demonstrates the utility of egg production measurements to further investigate the causes and solutions to the effects of mill effluents in both freshwater and marine wild fish.

Transgenerational effects of polycyclic aromatic hydrocarbon exposure on sheepshead minnows (Cyprinodon variegatus)

“…Although low HEWAF exposure increased F 0 egg production, the eggs that were produced experienced developmental deficits, which may affect survival in a natural habitat. The biphasic dose–response pattern (“hormesis”) observed in F 0 egg production in the present study is a well‐documented phenomenon in toxicology (Calabrese et al ) and has been demonstrated in fish reproduction studies (Pawlowski et al ; Tilton et al ; Bosker et al ; van den Heuvel et al ). High variability between tanks lowered statistical power and limited interpretation of F 1 egg production data.…”