The toxicity of mixtures of metals and surfactants to rainbow trout (Salmo gairdneri rich.)

The toxicity to rainbow trout of two metals (copper and mercury) and three detergents (two anionics and one non-ionic) were determined with an exposure period of 14 days. Each compound was tested separately and as a metal-detergent pair. The results show that for the mixtures of anionic detergents and metals a “more-than-additive” effect exists, while for the mixture of non-ionic detergent and metal the toxic effect is probably “less-than-additive”. These findings are compared with existing data in the literature and the underlying reasons for these effects are discussed.