Polychlorinated biphenyls adverse health effects

High-level exposure to polychlorinated biphenyls can cause adverse health effects ranging from developmental effects in children to increased risk from cancer. Children born to exposed mothers have exhibited long-term adverse effects on cognitive development. 

Swanson GM, Ratcliffe HE, Fischer LJ. 1995. Human exposure to polychlorinated biphenyls (PCBs) a critical assessment of the evidence for adverse health effects. Regul Toxicol Pharmacol 21(1) 136-50. 

Polychlorinated biphenyls are moderately toxic substances that have been found to cause cancers in animals and to induce birth defects. Occupational exposure to PCBs exhibit a broad range of adverse health effects on the skin, eyes, mucous membranes, and digestive and neurological systems. The... 

Using traditional methods of whole-water analysis, concentrations of these HCs are usually underestimated. Indeed, by these methods HCs may not even be detected, although they may occur on sediment at concentrations likely to have toxic effects on biota. The conventional approach for determining the concentration of HCs on suspended sediment is to analyze a whole-water sample and a filtered water sample and to assume that the difference between the two represents the fraction sorbed to suspended sediment. The major problem with this approach is that the amount of suspended sediment and associated contaminant in the whole-water sample may not be sufficient to produce a detection by whole-water analysis methods. This is particularly true if the suspended sediment concentration in the sample is small, as is generally the case for springs relative to surface water. For example, if a sample contains 50 mg/L of suspended sediment, and the sediment contains 300 pg/kg of polychlorinated biphenyls (PCBs) (a concentration likely to adversely affect biota health (Environment Canada, 1998)), the concentration of PCBs in the whole-water sample will be 0.015 pg/L. This concentration is well below most laboratory method detection limits—for example, the USGS National... 

These chemicals are considered in a pollution category because both deliberate and accidental release to the environment of several of these types of compounds, for example the industrial chemicals such as PCBs (polychlorinated biphenyls) and the chlorinated pesticides p,p DDT (dichlorodiphenyl-trichloroethane formal chemical name l,l -(2,2,2-trichloroethylidene)-bis (4-chlorobenzene)), have had unintended adverse environmental effects on diverse plants and animals and on people. Initially, chemicals such as PCBs and DDT were beneficial to human civilization PCBs as industrial chemicals allowing economical, safe delivery of electricity, and DDT as a pesticide eradicating vector pests of human health concern and agricultural crop pests. Only after these chemicals had entered widespread use did it become apparent that there were environmental problems, although in hindsight there was evidence of potential problems early in the history of their manufacture and use. 

With few exceptions (c.g., DES), a causal relationship between exposure to a specific environmental agent and an adverse effect on human health operating via an endocrine disruption mechanism has not been established. Short-term screening studies could be developed and validated in an effort to elucidate the mechanism. Through controlled dose-response studies, it appears that these compounds (e.g., alkyl phenol ethylates and their degradation products, chlorinated dibenzodioxins and difurans, and polychlorinated biphenyls) can induce irreversible induction of male sex characteristics on females (impo-sex), which can lead to sterility and reduced reproductive performance. 

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