Abstract
Water quality guidelines have been derived to protect aquatic ecosystems in the regulatory framework of many countries. Direct toxicity assessment（DTA）or whole effluent toxicity（WET）testing has been conducted to estimate the toxicity of complex mixture such as industrial effluents using various bioassays. Most countries adopted acute and/or chronic crustacean toxicity tests in their regulations. In this paper, sensitivities and practical aspects of crustacean toxicity tests were compared for three crustacean species, Daphnia magna（OECD Guidelines 202 and 211）, Ceriodaphnia dubia（EPA/600/4-90-027F）and Mysidopsis bahia（EPA/821/R-02-013）. Results indicate that the D. magna acute toxicity test is the most appropriate method in regulatory aspects
