Toxicity of binary chemical mixtures: effects on reproduction of zebrafish (Brachydanio rerio).

A complete life-cycle test with zebrafish was carried outwith different concentrations of the binary mixture 3,4-dichloroaniline andlindane under flow-through conditions. Length and weight of fish of theF1-generation were reduced, even in the lowest test concentrationof 2 microg/L 3,4-dichloroaniline and 40 microg/L lindane. The same effects werefound in the early life stage test for the F2-generation. In themixture of 100 microg/L 3,4-dichloroaniline and 40 microg/L lindane, fish whichwere exposed for their whole life time stopped spawning, irreversibly; thefish population will become extinct. In an additional experiment, fish wereexposed to the same xenobiotic concentrations after reaching maturity. Inthis case, egg production was reduced. Cessation of egg production occurs ina concentration of 200 microg/L 3,4-dichloroaniline and 40 microg/L lindane.Nevertheless, effects on spawning are influenced by duration of exposure andthe life stages of exposure.