Chemicals in the class:
Found in these people:
Baby #1, Baby #2, Baby #3, Baby #4, Baby #5, Baby #6, Baby #7, Baby #8, Baby #9, Baby #10, Anonymous Adult 1, Kathy Fowler, U.S. Representative Louise Slaughter, Sara Corbett, Cord Blood Sample 11, Cord Blood Sample 12, Cord Blood Sample 13, Cord Blood Sample 14, Cord Blood Sample 15, Cord Blood Sample 16, Cord Blood Sample 18, Cord Blood Sample 19, Cord Blood Sample 20
Found in these locations:
Rockville, MD; Upstate New York, NY; NY, USA
Laboratory animals. In animal studies, PCBs cause a wide variety of effects including liver and thyroid tumors; kidney, gastrointestinal, immune, urinary tract, and reproductive toxicity; altered lipid and carbohydrate metabolism; nail and nail bed changes; reduced fertility and birth defects. Specific birth defects include reproductive tract and skeletal abnormalities. PCBs are endocrine disruptors because they alter thyroid and adrenal hormone levels and function. PCBs cause significant neurotoxicity, including decreased exploratory behavior, learning, spatial and non-spatial discrimination, auditory deficits and altered levels of brain neurotransmitters (dopamine and serotonin) (ATSDR 2000b).
Humans. The effects of PCBs have been studied in humans who were exposed through diet, work, and industrial accidents. PCBs are reasonably anticipated to be human carcinogen (NTP 2002). They are associated with skin, liver, biliary tract, and intestinal cancers. Other effects of PCBs include respiratory effects, gastrointestinal damage (nausea, vomiting, abdominal pain), eye irritation, increased susceptibility to infection, and hypothyroidism (ATSDR 2000b, Persky, et al. 2001). Other possible health effects associated with PCB exposure are menstrual irregularities and decreased fertility in women. Inconsistent associations have been noted with non-Hodgkin's lymphoma, breast cancer, cardiovascular disease, sperm and fertility in males, low birth weight and head circumference (ATSDR 2000b). PCB exposure in the womb or during lactation is also associated with decreased IQ and impaired psychomotor development, decreased immune function, altered liver enzyme and lipid levels, and skin disease (chloracne) (ATSDR 2000b).
Polychlorinated biphenyls, or PCBs, are toxic, persistent, bioaccumulative, and lipophilic ("fat-loving"). This means that PCBs build up and are stored in fatty tissues and fluids, such as breast milk, and can be passed on to fetuses and infants during pregnancy and lactation. In humans PCBs are linked to increased rates of a number of cancers, including malignant melanoma; non-Hodgkin's lymphoma; and brain, liver, and lung cancer. PCB poisonings in humans have caused fetal and infant death, birth defects, and brain damage in children exposed in the womb. PCBs are known to interfere with hormonal processes. In 1976, the manufacture of PCBs was banned in the United States because of concern for human health impacts, but are still widely found in the general population of the U.S.
In humans, PCBs are associated with skin lesions, thyroid disruption, and altered menstrual cycling, as well as damage to the nervous, immune, and cardiovascular systems. PCB exposure in the womb or during lactation is also associated with decreased IQ and impaired psychomotor development, decreased immune function and skin disease (chloracne) (ATSDR 2000b). The National Toxicology Program considers several PCB mixtures to be "reasonably anticipated" human carcinogens (NTP 2002). Likewise, EPA considers PCBs to be "probable" human carcinogens (EPA 2002b).
In laboratory animals, PCBs are known to cause cancer and damage to the reproductive, endocrine, immune, and nervous systems. In addition, PCBs damage the kidney and gastrointestinal tract, and cause birth defects.
Mono-PCB has been found in 25 of the 25 people tested in EWG/Commonweal studies.
Top health concerns for Mono-PCB (References)
|health concern or target organ||weight of evidence|
|Brain and nervous system||unknown|
|Immune system (including sensitization and allergies)||limited|
Toxicity Classifications (References)
|Limited evidence in humans - immune system toxicity||ATSDR (2000). Toxicological profile for polychlorinated biphenyls (PCBs): Health effects chapter. http://www.atsdr.cdc.gov/tfacts17.html|
|Nervous system toxicity - weight of evidence unknown/unassessed||ATSDR (2000). Toxicological profile for polychlorinated biphenyls (PCBs): Health effects chapter. http://www.atsdr.cdc.gov/tfacts17.html|