Agricultural and Environmental Chemistry Graduate Group and Department of Civil and Environmental Engineering, University of California at Davis, Davis, California 95616, USA.
Environ Sci Technol. 2010 Jul 1;44(13):4951-7. doi: 10.1021/es100094f.
Controlled rainfall experiments utilizing drop-forming rainfall simulators were conducted to study various factors contributing to off-target transport of off-the-shelf formulated pyrethroid insecticides from concrete surfaces. Factors evaluated included active ingredient, product formulation, time between application and rainfall (set time), and rainfall intensity. As much as 60% and as little as 0.8% of pyrethroid applied could be recovered in surface runoff depending primarily on product formulation, and to a lesser extent on product set time. Resulting wash-off profiles during one-hour storm simulations could be categorized based on formulation, with formulations utilizing emulsifying surfactants rather than organic solvents resulting in unique wash-off profiles with overall higher wash-off efficiency. These higher wash-off efficiency profiles were qualitatively replicated by applying formulation-free neat pyrethroid in the presence of independently applied linear alkyl benzene sulfonate (LAS) surfactant, suggesting that the surfactant component of some formulated products may be influential in pyrethroid wash-off from urban hard surfaces.
利用滴形降雨模拟器进行了控制性降雨实验，以研究导致市售拟除虫菊酯杀虫剂从混凝土表面非目标迁移的各种因素。评估的因素包括有效成分、产品配方、施药后到降雨的时间（设定时间）和降雨强度。根据产品配方，施用到表面的拟除虫菊酯有多达 60%和少至 0.8%可能随地表径流流失，而产品设定时间的影响较小。在一小时暴雨模拟过程中，根据配方可以对冲刷曲线进行分类，使用乳化表面活性剂而不是有机溶剂的配方会产生独特的冲刷曲线，总体冲刷效率更高。在独立施加线性烷基苯磺酸盐（LAS）表面活性剂的情况下，施加无配方的纯拟除虫菊酯可以定性地复制这些更高的冲刷效率曲线，这表明一些配方产品中的表面活性剂成分可能会影响城市硬表面上拟除虫菊酯的冲刷。
