The acute and chronic toxicity of technical chlordane to bluegill (Lepomis macrochirus), fathead minnow (Pimephales promelas), brook trout (Salvelinus fontinalis), Daphnia magna, Hyallela azteca, and Chironomus No. 51 were determined with flow-through conditions. The purpose was to estimate concentrations producing acute mortality and those having no effect on the long-term survival, growth, and reproduction of the various species. Whole body residues of technical chlordane components were measured in the three invertebrate species at the end of the chronic exposure tests. Concentrations of technical chlordane causing 50% mortality in 96 hr were 36.9 micrograms/1 for fathead minnow, 47 micrograms/1 for brook trout, and 59 micrograms/1 for bluegill, while that causing 50% immobilization in the cladoceran, D. magna, was 28.4 micrograms/1. The amphipod, H. azteca, was only slightly affected at 96 hr by the chlordane concentrations tested, and the 168-hr LC50 was 97.1 micrograms/1. Acute mortality of midges, Chironomus No. 51, was not successfully evaluated.

Prepared for the U.S. Environmental Protection Agency, Office of Research and Development, Environmental Research Laboratory, Duluth, Minn., under contract no. 68-01-0187. Includes bibliographical references (pages 81-89). Microfiche.