Author(s): Jinfeng Ma; Qiuwen Chen; Fei Ye; Yiping Xu
Keywords: Cute Ecological risk assessment; Contaminant fate model; Water pollutionaccidents; Ecotoxicology
Abstract: : Water pollution accidents has become a continuous concern due to its adverse effects on aquatic ecosystems, which are generally characterized by short term-high level exposures and particularly, dynamical fluctuations of exposure concentrations. Consequently, an efficient, quantitative approach to aquatic ecosystem risk assessment (ERA) remains a longstanding challenge in water pollution accidents. Although toxicity exposure ratio (TER) methodology overwhelming in ERA studies, predicted environmental concentration (PEC) determination still adopted the maximum concentration in receiving water, without taking into consideration of dynamical fluctuations of concentration and leading to a underestimation of potential risks. This studypresented a PEC determination method based on the pollutant transport modeling to reflect effect of the temporal and spatial variability of concentration field on ecological risk. The pollutant transport model employs SELFE and WASP to compute the spatial-temporal distributions of pollutant. Basing on the pollutant concentration field, the presented PEC determination method is employed tocharacterizethe ecotoxicological effects on ecosystem. The method is validated by the data collected from an accidental spill of nitrobenzene happened in November 2005 in the Songhua River, China.