Environmental chemistry of pentachlorophenol

Abstract

Pentachlorophenol (PCP)a is a major industrial chemical and a general biocide used throughout the world. PCP, itself, is corrosive and toxic, but it also is readily degraded by sunlight, animals, plants, and soil microorganisms. Several analytical methods — especially gas chromatography — have become established which permit routine detection and measurement at environmental levels below 1:109, and PCP residues have been detected widely in food, water, and human urine in approximately the 1:108 to 1:1010 range (and higher under occupational conditions). However, technical PCP contains many neutral impurities including hexa-, hepta-, and octachlorodibenzodioxins, chlorinated dibenzofurans, phenoxyphenols, and hexachlorobenzene, which are more slowly metabolized or environmentally degraded and some of which are extremely toxic. Sophisticated analytical methods to detect the presence of the dibenzodioxins and dibenzofurans have not yet received wide application, and evidence of the environmental occurrence of these substances is fragmentary. Although commercial PCP can be partially purified, the toxicity and mobility of both the parent compound and its impurities suggest that indiscriminate use of PCP products and the exposure of humans and domestic animals should be minimized. In addition, PCP occurs as a metabolite of several common pesticides which may contribute substantially to both observed environmental residues and human exposure. © 1981 IUPAC