特丁硫磷在环境中的迁移性研究

采用室内模拟试验方法,研究了有机磷类农药特丁硫磷在不同环境介质中的挥发性以及在3种不同类型土壤中的吸附性、移动性及其影响因素。结果表明:特丁硫磷具有较强的挥发性,其在空气、土壤表面和水中的挥发率分别为87.1%、38.6%和2.51%;在江西红壤、太湖水稻土与东北黑土中的吸附性较好地符合Freundlich方程,3种土壤中的吸附系数Kd值分别为6.56、11.34和15.80;薄层层析试验显示,当溶剂展开至12.0 cm时,特丁硫磷在江西红壤、太湖水稻土与东北黑土中最远可分别移至6~8、4~6和6~8 cm处,土柱试验结果显示,江西红壤、太湖水稻土与东北黑土淋出液中特丁硫磷质量分数分别为5.77%、1.13%和1.22%,表明特丁硫磷具有一定的移动性。影响特丁硫磷在土壤中吸附性和移动性的主要因素为土壤有机质含量,其次为土壤质地。特丁硫磷具有高挥发性及一定的移动性,其对人畜的安全以及地下水的危害应引起高度重视。

Migration characteristics of terbufos in the environment

The volatility in different media,the adsorption and mobility of terbofus in three different soils were studied in laboratory in accordance with the criterion for chemical pesticide environmental safety assessment.The results showed that terbofus had high volatility,the volatilization rate were 87.1%,38.6% and 2.51% in atmosphere,soil surface and water,respectively.The adsoption of terbufos in Jiangxi red soil,Taihu paddy soil and Northeast China black soil were better fitted by the empirical Freundich adsorption isotherm.The adsorption constant (K_d) in Jiangxi red soil,Taihu paddy soil,Northeast China black soil were 6.56,11.34 and 15.80.TLC results showed that when the solvent expanded to 12.0 cm,terbufos in Jiangxi red soil,Taihu paddy soil and the Northeast black soil can be moved to the location of 6-8 cm,or 4-6 cm and 6-8 cm.Soil column test showed that,mass percentages of terbufos in the leachate of Jiangxi red soil,Taihu paddy soil and the Northeast black soil were 5.77%,1.13% and 1.22% ,respectively.The result of the mobility test showed that terbufos can move in the test soils.The content of organic matter was the primery factor which affected the adsorption of terbufos in soils,and the soil texture was the secondary one.It showed that terbufos is a pestivide with removable and highly volatile characteristics and the potential risks for groundwater pollution and the safety of human and domestic animals,to which should continue to pay close attention.