Liang T T, Lichtenstein E P
Science. 1974 Dec 20;186(4169):1128-30. doi: 10.1126/science.186.4169.1128.
The synergism of parathion and p,p'-DDT [1,1,1-trichloro-2,2-bis-(p-chlorophenyl)ethane] by atrazine was investigated as a function of soil type, age of pesticide soil residues, and the presence of soils in quiet or turbulent water. Compared to previous tests in which the pesticides were applied on glass surfaces, a significant reduction of the toxicity of the insecticides to fruit flies and of the synergistic effects of atrazine was observed with soils, particularly a silt loam. The effects of atrazine as a synergist in soil declined rapidly within 4 days. The toxicity of parathion in water and its synergism by atrazine were significantly reduced by soil sediments, depending on the type and amount of soil present. Soils were highly effective in turbulent water: in water containing the relatively high parathion concentration of 0.3 part per million, 93 percent of the mosquito larvae present died within 24 hours, yet this solution was rendered nontoxic by being mixed with 5 grams of a loam soil. With atrazine present in the latter system, however, 38 percent of the mosquito larvae died. Thus, insecticides can be more or less toxic, depending on their concentrations, the presence of synergists, and the environmenetal conditions.
研究了莠去津对杀螟硫磷和p,p'-滴滴涕[1,1,1-三氯-2,2-双-(对氯苯基)乙烷]协同作用的影响，该协同作用是土壤类型、农药土壤残留时间以及土壤处于静水或动水中等因素的函数。与之前在玻璃表面施用农药的试验相比，发现土壤（尤其是粉质壤土）会使杀虫剂对果蝇的毒性以及莠去津的协同效应显著降低。莠去津作为增效剂在土壤中的效果在4天内迅速下降。土壤沉积物会显著降低杀螟硫磷在水中的毒性及其与莠去津的协同作用，这取决于沉积物的类型和数量。土壤在动水中效果显著：在含有百万分之0.3相对高浓度杀螟硫磷的水中，93%的蚊子幼虫在24小时内死亡，但通过与5克壤土混合，该溶液会变得无毒。然而，在后者体系中加入莠去津后，有38%的蚊子幼虫死亡。因此，杀虫剂的毒性大小可能会因浓度、增效剂的存在以及环境条件而有所不同。
