Determination of the acute toxicity of rotenone and Bayer 73 to selected aquatic organisms

Abstract

The acute toxicity of Bayer 73 to carp (Cyprinus carpio) and green sunfish (Lepomis cyanellus), the effects of sediment and ultraviolet radiation, and the standard curve for Bayer 73 were determined. The toxicity of Bayer 73 to carp increased with the increase in exposure time. The toxicity to carp and green sunfish decreased with an increase in harness and pH. The presence of sediment particles does not appear to affect the efficacy of Bayer 73. Exposure of Bayer 73 to ultraviolet light for 96 hours did not affect its toxicity to carp. Fifty ug/1 of Bayer 73 reduced the growth of Chlamydomonas sp. and Chlorella vulgaris by 50%. No growth of either species occurred when exposed to 100 ug/1 of Bayer 73. The toxicity of two formulations of rotenone, (Nox fish and Dri-Noxfish) were tested on frogs (Rana pipiens), crayfish (Orconectes immunis), scuds (Gammarus limnaeus), caddisflies (Hesperophylax sp.), and clams (Lampsilis sp.). Both formulations of rotenone are less toxic to the non-fish organisms than to fish. The effect of total hardness, pH, and exposure time varied with the organism tested. The toxicity of Dri-Noxfish was generally greater than Noxfish.