Toxicity of Diazinon 60 EC for Cyprinus carpio and Poecilia reticulata

摘要

Diazinon 60 EC (chemical insecticide, organophosphate, active substance diazinon at a concentration of 600 g lu-1) is used in fish-farming in well-founded cases as a biocide to suppress excessive propagation of coarse Daphnia zooplankton. At the concentration of 10 ^kg lu-1 (i.e., 100 g per 1 ha at a mean depth of the pond of 1 m), Diazinon 60 EC can highly selectively eliminate Daphnia zooplankton, causes no harm to fish, and relatively quickly decomposes in the aquatic environment. This has been corroborated by results of acute toxicity tests in fish: the 96 h LC50 is 3 mg lu-1 for the guppy (iPoecilia reticulata) and 10-25 mg lu-1 for the common carp (iCyprinus carpio). As demonstrated by embryonic and larval tests of toxicity for the common carp (iC. carpio), Diazinon 60 EC at the concentration of 10 ^kg lu-1 causes no harm to the tested, individuals even in these sensitive (critical) stages of ontogeny.