Latimer, D.L., A.S. Brooks & A.M. Beeton. (1975). Toxicity of 30-minute exposures of residual chlorine to the copepods Limnocalanus macrurus and Cyclops bicuspidatus thomasi. Journal of the Fisheries Research Board of Canada. 32(12):2495-2501, tabs. 1-3. (xii-1975).
Toxicity of 30-minute exposures of residual chlorine to the copepods Limnocalanus macrurus and Cyclops bicuspidatus thomasi.
Journal of the Fisheries Research Board of Canada
32(12):2495-2501, tabs. 1-3. (xii-1975)
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The intermittent chlorination of power plant cooling waters often results in the appearance of residual chlorine in the receiving waters. Laboratory bioassays were conducted at 5, 10, 15, and 20 C to determine the toxicity of residual chlorine exposures of 30 min to the copepods Limnocalanus macrurus and Cyclops bicuspidatus thomasi. The 30-min TL-50 was 1.54 mg/liter for L. macrurus at both 5 and 10 C. For C. b. thomasi, the 30-min TL-50 values for exposures at 10, 15, and 20 C were 14.68, 15.61, and 5.76 mg/liter, respectively. The concentrations of residual chlorine causing 5% mortality (30-min TL-5) were used to predict "safe" levels for 30-min exposures. The predicted "safe" concentrations were 0.9 mg/liter for L. macrurus and 0.5 mg/liter for C. b. thomasi. These concentrations roughly coincide with the maximal chlorine levels characteristic of most power plant effluents.