Worldwide Regulatory Guidance Values Applied to Direct Contact Surface Soil Pesticide Contamination: Part II—Noncarcinogenic Pesticides

Abstract

Surface soil regulatory guidance values (RGVs) are available worldwide for nearly 800 pesticides. Part I of this study examined values applied to commonly used carcinogenic pesticides. Part II examines RGVs applied to 12 commonly used noncarcinogenic pesticides: 2,4-D, carbaryl, carbofuran, chlorpyrifos, diazinon, dicamba, diuron, glyphosate, malathion, MCPA, metolachlor, and picloram. The RGVs applied by 38 nations vary by as much as 9.3 orders of magnitude, but the RGV distributions do not fit the lognormal random variable model as well as those reported for other contaminants, and there are value clusters in each distribution. The largest clusters contain values similar to current or previous US Environmental Protection Agency, Australian national, and former USSR values. Because these pesticides are used worldwide, it is important that their RGVs protect human health. Analysis indicates that this goal has not yet been achieved for chlorpyrifos and MCPA.