Effects of Temperature on the Acute Toxicity and Uptake of Lindane by Chironomus riparius (Meigen) (Diptera: Chironomidae)

Effects of temperature on toxicity of lindane to the midge Chtronomus riparius (Meigen) were studied. The toxicity of lindane increased from 13.43 ppm to 6.63 ppm as temperature increased from 15 to 25°C (positive temperature coefficient). An LC50 of 6.77 ppm was obtained when temperature was increased to 35°C. Since the toxicity of lindane did not change significantly when temperature was increased from 25 to 35°C, the temperature coefficient for this interval is neutral. Uptake studies using 14C-Iindane demonstrated that differential toxicity is attributable in part to differential absorption and, in part, to altered susceptibility of the target site at temperature extremes.