The Aquatic Organism Criteria Deltamethrin And Atrazine In The Yangtze River Delta Region

Pesticides can get into surface water by runoff and get into groundwater by leaching, which cause water pollution and harmful effects to aquatic organisms and human health. Water quality standard play an important role in environmental management, while water quality criteria can provide scientific basis for water quality standard formulation. Pesticides were widely used in China and water pollution caused by pesticides has become more and more serious, however research of water quality criteria is still at the early stage in China, especially the research of water quality criteria for pesticides.The sensitivity of aquatic organisms to pesticide in different regions is different. Aquatic organism criteria for pesticide should be based on toxicity data of the representative aquatic species in a particular area. The Yangtze River Delta Region is one of the regions with the maximum usage and production of pesticide in China.In this paper, the Yangtze River Delta Region was selected as the study area, and studies were conducted as following:(1) Systematic comparision were conducted among the assessment factor method, species sensitivity distributions, toxicity percentile rank method and ecological toxicology model method. Different model fitting results of pesticide toxicity data sets on the species sensitivity distribution method were compared, and then the fitting curve model of pesticide toxicity data set species sensitivity distribution were purposed. (2) Acute and chronic toxicity test for Deltamethrin were conducted using 14 kinds of representative of aquatic organisms of the Yangtze River Delta Region so as to obtain acute and chronic criteria value. (3) As a herbicide, Atrazine having endocrine disrupting effects. Acute, chronic and endocrine disrupting toxicity test for Atrazine were conducted. Aquatic organisms criteria of Atrazine were derived using the derivation method.The results showed:(1) when use species sensitivity distributions method to derive criteria for pesticides, Sigmoid, Gaussian, Gompertz and Exponential Growth should be selected to get fitting curves firstly, then the most optimal model which was used to derive the final value of water quality criteria could be determined, so as to ensure the scientificity of water quality criteria. (2) Eventually, we suggested water quality criteria values that those were derived by species sensitivity distribution. The acute and chronic criteria value of Deltamethrin were 0.0052,0.00038μg/L; For Atrazine, endocrine disrupting effects criteria value served as chronic criteria value. Therefore the acute and chronic criteria value of Atrazine were 2.60,0.0071μg/L.