Study On Characteristics And Risk Assessment Of Pesticide Non-point Pollution In The Typical Drinking Water Of Guizhou

Based on the investigation of pesticides used in guizhou and the drinking water source, determine researched on 666s(α-666, β-666, γ-666, δ-666), Chlorothalonil, Chlorpyrifos, Glyphosate, Pythium, Triadimefon, Fenpropathrin 10 kinds of pesticides, in the Hongfeng lake, Baihua lake and Aha reservoir, analyzing the characteristic of the target pesticides and the pollution sources in the water, studiing the gap with environmental standards limit, analysising of the literature results with the study, modifing the model parameters in combination with the practical situation of Guizhou, use it assess health risk assessment and ecological risk assessment for the preliminary. The main conclusions of this paper are as follows:⑴The objective analysis of pesticides is detected in “the two lakes and a reservoir”, and Hongfeng lake checked out kinds of pollutants much more than Baihua lake, Aha reservoir.But the content of different pesticides are difference, and detected pesticide content in spring is higher than the wet season and the dry season.At the same time, the detection rate of 666 s is higher than other pesticides.The order of the detected rate is β-666, α-666, γ-666, δ-666,concentration range of nd~35.1μg/L, nd~35.6μg/L, nd~34.2μg/L, nd~16.2μg/L, the highest concentration are in the spring, the three drinking water source have been polluted of varying degrees.Tributaries is mainly detected 666 s, Triadimefon and Procymidone.⑵The value of α/γ- 666 is range of 0.61~1.08, far less than 3, show that 666 s mainly come from the use of Lindane, a few comes from environmental residue; Chlorothalonil, Triadimefon, Pythium, Fenpropathrin, Chlopyrifos, Glyphosate’s detection rate and content is related to its used season, is derived from the part of not be used pesticide sprayed on the crops and tributary contribution.⑶ Chlorothalonil exceeds the Environmental quality standard for surface water(GB3838-2002) 1.12 times in H2 section of Hongfeng lake in wet season.The rest of the target analytes in the sample section are below the limits.⑷The highest personal annual total health risk value is in spring of drinking water source, is 10-4 orders, far more than the Dutch ministry of construction and environmental protection, The royal society, Swedish EPA maximum acceptable risk level 1×10-6a-1, US EPA maximum acceptable risk level 5×10-5a-1, The international radiation protection committee maximum acceptable risk level 1×10-4a-1, at a higher level of risk. Wet season is higher than dry season, but all are below 5×10-5a-1 and 1×10-4a-1, swings around 1×10-6a-1, existing some risks. Detection of pesticide personal annual total risk from high to low in turn for α-666, β-666, γ-666, Chlorothalonil, Triadimefon, Fenpropathrin, Glyphosate.⑸The detected pesticide has certain ecological risk in fish, amphibians and aquatic organisms in the study, but all the detected pesticide of chronic RQ are less than 1, for the fish, amphibians acute RQ are different. Ecological risk from high to low in turn for γ-666, Chlorpyrifos, Chlorothalonil, Triadimefon, Fenpropathrin, Clyphosate.