Toxicological profile of chlorophenols and their derivatives in the environment: the public health perspective

Abstract

Chlorophenol compounds and their derivatives are ubiquitous contaminants in the environment. These compounds are used as intermediates in manufacturing agricultural chemicals, pharmaceuticals, biocides, and dyes. Chlorophenols gets into the environment from a variety of sources such as industrial waste, pesticides, and insecticides, or by degradation of complex chlorinated hydrocarbons. Thermal and chemical degradation of chlorophenols leads to the formation of harmful substances which constitute public health problems. These compounds may cause histopathological alterations, genotoxicity, mutagenicity, and carcinogenicity amongst other abnormalities in humans and animals. Furthermore, the recalcitrant nature of chlorophenolic compounds to degradation constitutes an environmental nuisance, and a good understanding of the fate and transport of these compounds and their derivatives is needed for a clearer view of the associated risks and mechanisms of pathogenicity to humans and animals. This review looks at chlorophenols and their derivatives, explores current research on their effects on public health, and proffers measures for mitigation.

Figure 1

Commercially the most important chlorophenols. 2,4-dicholorophenol (2,4-DCP) (1); pentachlorophenol (PCP) (2); 2,4,5-trichlorophenol (2,4,5-TCP) (3); 2-chlorophenol (2-CP) (4) and 4-chlorophenol (4-CP) (5).