禁限用有机磷农药持久性、生物累积性和毒性评估

Assessment of Persistence, Bioaccumulation and Toxicity of Restricted Organophosphorous Pesticides

采用EPI Suite计算和数据检索的方式对比评估了农业农村部禁限用25种有机磷农药(OPPs)的持久性、生物累积性和毒性(PBT)。结果表明,已禁用OPPs中,甲胺磷和磷胺的环境持久性最强;蝇毒磷和特丁硫磷的logBCF值>2.7,生物累积效应明显;甲基对硫磷的水蚤急性毒性最强,48 h-LC50值为0.14μg/L;特丁硫磷和对硫磷对大鼠的毒性最强,LD50(经口)均为2 mg/kg;对硫磷浓度为0.2 mg/L时可使人体淋巴细胞的姐妹染色单体发生交换,有潜在遗传毒性。部分禁用的乙酰甲胺磷在25种OPPs中环境持久性最强,而毒死蜱的生物累积性最强(logBCF值为3.3);毒死蜱的水蚤48 h-LC50为0.1μg/L,内吸磷对大鼠的LD50(经口)为1.7 mg/kg;毒死蜱、甲拌磷和乐果引起姐妹染色单体交换的浓度均为2 mg/L。PBT特性评估结果表明,25种OPPs均具有一定环境风险,其中甲基对硫磷、乙酰甲胺磷、毒死蜱、甲拌磷等应考虑作为优先污染物从水体、土壤等环境介质中予以去除。

The persistence,bioaccumulation and toxicity(PBT)of 25 OPPs restricted by the ministry of agriculture and rural affairs are assessed via applying EPI Suite calculation and database query.The results show that for the banned OPPs,methamidophos and phosphamine have the strongest environmental persistence.The logBCF value of muscarinate and terbutafo are both>2.7,which indicates obvious bioaccumulation effects;the 48 h-LC50 of methyl parathion to daphnia magna is the highest;terbutafo and parathion are the two most toxic OPPs to rat(oral)with LD50 of 2 mg/kg.Parathion could cause sister chromatid exchange to human lymphocyte at 0.2 mg/L,which implies potential genotoxicity.For partially banned OPPs,acephate has the highest environmental persistence and the bioaccumulation of chlorpyrifos is the strongest(logBCF 3.3),among 25 OPPs.The 48 h-LC50 of chlorpyrifos to daphnia magna is 0.1μg/L.LD50 of demeton to rat(oral)is 1.7 mg/kg.Chlorpyrifos,phorate and dimethoate all could cause sister chromatid exchange of human lymphocyte at 2 mg/L.The assessment results of PBT characteristics shows potential environmental risks of all 25 OPPs,among which methamidophos,acephate,chlorpyrifos and phorate should be treated as priority pollutants to be removed from waters,soils and other environmental media.