The acute toxicity of dechlorinated DDT, chlordane and lindane to the bluegill (Lepomis macrochirus) and water flea (Daphnia magna)

Abstract

In order to assess the effects of catalytic dechlorination by nickel boride upon the toxicity of chlorinated insecticides, static bioassays of DDT, chlordane and lindane, before and after treatment in a nickel boride/sodium borohydride/methanol system, were run with bluegill and daphnia. Technical and military standard formulations of each insecticide were studied. Dechlorination significantly reduced the toxicity of each insecticide. Ninety-six-hour bluegill LC50's were increased by as much as 1450-fold for lindane, 1036-fold for DDT, and 14-fold for chlordane. Forty-eight-hour daphnia EC50's were increased by as much as 149-fold for DDT, 38-fold for lindane, and 8-fold for chlordane. Catalytic dechlorination by nickel boride appears to be a practical method for detoxifying small quantities of lindane. DDT and chlordane retained a high degree of toxicity and so would require additional treatment. Further research needs are discussed.