The calculation method of acute effect threshold for toxic pollutants in water pollution accident

In recent years, China´s water pollution accidents, resulting in acute aquatic ecological risk and security issues become a focus of the study. However, in our country, the surface water quality standards and drinking water health standards ware used to determine the safety of waters or not when pollution incidents happen, and lacking safety effect threshold for protection of aquatic life. In foreign countries, although predicted no effect concentration (PNEC) of pollutants were provided for protection of aquatic organisms, the calculation of the PNEC is based on chronic toxicity data NOECs (no observed effect concentrations), and its ecological risk value is also based on the risk of long-term exposure. The effect thresholds of chemicals ware lack under short-term and high dose exposure in water pollution incident. For the short-term and high dose exposure in pollution incident, ecological effects tthreshold calculation method were discussed according to the conventional PNEC calculation method and the water quality criteria establishment method of the U.S. EPA for the protection of aquatic organisms under short-term exposure, and had practical application.