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PCBs may play a role in the development of cancers of the immune system because some tests of laboratory animals subjected to very high doses of PCBs have shown effects on the animals' immune system, and some studies of human populations have reported an association between environmental levels of PCBs and immune response.
Because current human evidence is incomplete, there is only data suggesting the carcinogenic effects of PCBs in humans. [15] While little research has been done on the toxic effects of 2,2’,3,3’,4,4’-hexachlorobiphenyl, PCBs have been found to cause irritation in the eyes and when inhaled also in the airways.
PCBs are human carcinogens, and can also have a negative effect on the human immune, reproductive, and endocrine systems. [4] PCBs in the Kalamazoo River adhere to the fatty tissue of fish, and over time a process of bioaccumulation takes place, meaning that the PCBs appear in increasing concentrations in organisms higher up on the food chain ...
Ortho-PCBs may alter hormone regulation through disruption of the thyroid hormone transport by binding to transthyretin. [8] Coplanar PCBs are similar to dioxins and furans, both bind to the aryl hydrocarbon receptor (AhR) in organisms and may exert dioxin-like effects, in addition to the effects shared with non-coplanar PCBs.
The PCB oil leaked to rice bran oil consumed by thousands of people in Japan (Yusho disease 1968) and Taiwan (Yu-cheng disease 1979). The toxic effects have been attributed to dioxin-like PCBs and PCDFs. Their daily intake was up to 100,000 times higher than average intake presently. [1]
Test results conducted in the fall showed the presence of PCBs, or polychlorinated biphenyls — toxic, man-made chemicals that were banned from being produced in the United States in 1979.
Immediate effects of PCB exposure include pigmentation of nails and mucous membranes and swelling of the eyelids, along with fatigue, nausea, and vomiting. Effects are transgenerational, as the chemical can persist in a mother's body for up to 7 years, resulting in developmental delays and behavioral problems in her children. Food contamination ...
In 1994, the US EPA reported that dioxins are a probable carcinogen, but noted that non-cancer effects (reproduction and sexual development, immune system) may pose a greater threat to human health. TCDD , the most toxic of the dibenzodioxins, is classified as a Group 1 carcinogen by the International Agency for Research on Cancer (IARC).