Worldwide Regulatory Guidance Values for Chlorinated Benzene Surface Soil Contamination

Abstract

AbstractSurface soil contamination is a worldwide problem that is often addressed by the use of regulatory guidance values (RGVs) that establish the maximum amount of contamination that may exist without prompting a regulatory response. Chlorinated benzenes are a family of 12 synthetic aromatic contaminants for which at least 168 jurisdictions have promulgated guidance values. Analysis of the 973 RGVs for the eight most commonly regulated chlorinated benzenes is presented. The RGVs of chlorobenzene, 1,2-, 1,3- and 1,4-diclorobenzene, 1,2,4-trichlorobenzene, 1,2,4,5-tetrachlorobenzene, and hexachlorobenzene vary by over six orders of magnitude. The RGVs for pentachlorobenzene vary by five orders of magnitude. The RGV distributions resemble those of lognormal random variables, but contain nonrandom clusters and extreme values that deviate from the lognormal distribution model. Point clusters appear to reflect the influence of organizations such as the U.S. Environmental Protection Agency (USEPA) and the Can...