Persistent Organic Pollutants: An Overview

Abstract

Persistent organic pollutant s ( POP s) are a class of organic compounds that are characterized by their ability to resist degradation through environmental processes, remaining intact for long periods of time. They are semi -volatile and capable of traveling as vapor or being absorbed to particulate matter in environmental media, facilitating long -range transport. Their persistence and mobility have resulted in their ubiquitous presence in the environment, as well as biota, including humans. These chemicals are found even in the most remote areas of the world, such as deserts, open ocean, and the poles, where there is no human activity nor chemical sources, demonstrating their ability to travel such long distances. POPs also are mostly lipophilic, bioaccumulating in fat tissues, and subsequently amplifying in concentration in biota occupying the upper spectrum on the food chain.Common types of POPs include polychlorinated biphenyl s ( PCB s), polychlorinated dibenzo -p -dioxins and furan s ( PCDD/F s), and polybrominated diphenyl ether s ( PBDE s), as well as organochlorine pesticides and fl uorinated compounds. Many are still and/or were intentionally used as pesticides or manufactured for a variety of consumer or industrial applications, whereas others are byproducts of industrial activities. Some examples include DDT, which is still used to control mosquitoes carrying malaria in certain regions of the world, and PCBs, which were used as cooling insulating fl uids for transformers and capacitors as well as paint and cement additives. These chemicals provided benefi cial and economical solutions, and thus were applied in a

Plant–bacteria partnerships for the remediation of persistent organic pollutants

“…The stability is further increased by increasing the number of chlorine atoms in the compound. Therefore, the compounds with higher halogenation are more resistant to degradation as compared to the compounds with lower halogenation (Wikoff et al 2012). …”

Maternal dioxin exposure and pregnancy outcomes over 30 years of follow-up in Seveso

“…The environmental contaminant 2,3,7,8-tetrachlorodibenzo- p -dioxin (TCDD) is a known carcinogen and potent endocrine disruptor, and is produced as an unintentional byproduct of several industrial processes (Baan et al 2009; Birnbaum 1995; Birnbaum 1994; IARC 1997; Wikoff et al 2012; Zook and Rappe 1994). TCDD is the most toxic congener of a group of structurally related compounds including polychlorinated dibenzodioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs) that bind with varying strengths to the aryl hydrocarbon receptor (IARC 1997).…”

Serum TCDD and TEQ concentrations among Seveso women, 20 years after the explosion

“…Polychlorinated dibenzo- p -dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) constitute a group of polyhalogenated aromatic hydrocarbons produced by chemical reactions and combustion processes (1, 2). These environmental contaminants are highly lipophilic, resist metabolism, and bioaccumulate; the general population of most countries has some level of background exposure (1–3).…”