You are here:
Organohalogen Pollutants and Human Health
Kodavanti, P. AND B. Loganathan. Organohalogen Pollutants and Human Health. Chapter 12, Encyclopedia of Public Health. ELSEVIER, AMSTERDAM, Holland, , 359-366, (2017).
It is axiomatic that human activities change the quality of the environment on a global scale, which can adversely affect life on earth. A prototypical example of such environmental damage and harmful biological effects is that caused by persistent human-made chemicals, particularly organohalogen compounds. Organohalogens are organic compounds that contain chlorine, bromine, fluorine atoms [named chlorinated (Figure I ), brominated (Figure 2), and fluorinated (Figure 3) compounds, respectively]. Due to their extreme persistence in the environment, bioaccumulative nature, and long term health effects in humans, some organohalogen compounds such as polychlorinated biphenyls (PCBs, an industrially versatile compound), insecticides such as DDTs, HCHs (BHC), chlordane (CHLs), and industrial byproducts such as chlorinated/brominated dioxins/dibenzofurans are wel l-known global environmental contaminants. Although the use of some of these synthetic chemicals has been banned or severely restricted in most developed countries more than four decades ago, these organohalogens are still found in almost all components of the global ecosystem and pose a threat to life on earth. Following the ban on their production and use, residue levels of those organohalogens have declined, but in some cases at a relatively slow rate. Nevertheless, new organohalogens continue to be discovered in the environment. Perfluorinated compounds (PFCs), polybrominated diphenyl ethers (PBDEs), triclosan, triclocarban, tetrabromobisphenol A (TBBPA) and hexabromocyc lododecanes (HBCDs) are widely used in a variety of industrial and consumer products and are considered as chemicals of emerging environmental concern on the global scale.
During the past century, a vast number of organic chemicals have been manufactured and used in industrial, agricultural, public health, consumer products and other applications. Widespread use of organohalogens, including chlorinated, brominated and fluorinated compounds, lead to environmental contamination and human exposures occurring through multiple pathways such as direct skin contact, inhalation, drinking water, and food. Exposure to these persistent organic pollutants (POPs) has been implicated in myriad huma n health effects including reproductive, neurotoxic, immunotoxic, endocrine, behavioral, and carcinogenic effects in both wildlife and humans. In addition, polybrominated diphenyl ethers (PBDEs), the perfluorinated chemicals (PFCs), triclosan, triclocarban , tetrabromobishphenol A (TBBPA) and hexabromocyclod odecane (HBCD) are considered as chemicals of emerging environ mental concern. Based on their use pattern and their persistent chemical properties, it can be predicted that human exposure to these compounds will continue. Human health effects due to such exposures also continue to be an issue of concern.