Fish low in contaminants are an important part of a healthy diet. PCBs in fish and shellfish PCBs, or polychlorinated biphenyls, are highly toxic industrial compounds.
What are PCBs and where do they come from? What are the health risks associated with consuming PCB-contaminated fish? For example, some recent studies found that: Children of mothers who ate fish with large amounts of PCBs from the Great Lakes had smaller head size, reduced visual recognition and delayed muscle development. A mother's exposure to PCBs and other chemicals was linked to slight effects on her child's birth weight, short-term memory, and learning.
Older adults 49 to 86 years old who ate fish containing PCBs and other contaminants had lower scores on several measures of memory and learning.
How can I reduce the risks of eating seafood contaminated with PCBs? PCBs build up in fish and animal fat, and therefore proper cooking methods can help reduce your exposure: Before cooking, remove the skin, fat found along the back, sides and belly , internal organs, tomalley of lobster and the mustard of crabs, where toxins are likely to accumulate. When cooking, be sure to let the fat drain away and avoid or reduce fish drippings.
Serve less fried fish; frying seals in chemical pollutants that might be in the fish's fat, while grilling or broiling allows fat to drain away. For smoked fish, it is best to fillet the fish and remove the skin before the fish is smoked. Most significantly, PCB exposures were found to reduce the birth weight, conception rates and live birth rates of monkeys and other species; and PCB exposure reduced sperm counts in rats.
Effects in monkeys were long lasting and were observed long after the dosing with PCBs occurred. Studies of reproductive effects have also been carried out in human populations exposed to PCBs. Children born to women who worked with PCBs in factories showed decreased birth weight and a significant decrease in gestational age with increasing exposures to PCBs. Studies in fishing populations believed to have high exposures to PCBs also suggest similar decreases.
This same effect was seen in multiple species of animals exposed to PCBs, and suggests that reproductive effects may be important in humans following exposures to PCBs. Proper development of the nervous system is critical for early learning and can have potentially significant implications for the health of individuals throughout their lives.
Effects of PCBs on nervous system development have been studied in monkeys and a variety of other animal species. Newborn monkeys exposed to PCBs showed persistent and significant deficits in neurological development, including visual recognition, short-term memory and learning. Some of these studies were conducted using the types of PCBs most commonly found in human breast milk. Studies in humans have suggested effects similar to those observed in monkeys exposed to PCBs, including learning deficits and changes in activity associated with exposures to PCBs.
The similarity in effects observed in humans and animals provide additional support for the potential neurobehavioral effects of PCBs. There has been significant discussion and research on the effects of environmental contaminants on the endocrine system "endocrine disruption". While the significance of endocrine disruption as a widespread issue in humans and animals is a subject of ongoing study, PCBs have been demonstrated to exert effects on thyroid hormone levels in animals and humans.
Thyroid hormone levels are critical for normal growth and development, and alterations in thyroid hormone levels may have significant implications. It has been shown that PCBs decrease thyroid hormone levels in rodents. Research has also shown that these decreases result in developmental deficits in rodents, including deficits in hearing. PCB exposures have been associated with changes in thyroid hormone levels in infants in studies conducted in the Netherlands and Japan. Additional research will be required to determine the significance of these effects in the human population.
Each IRIS assessment can cover a chemical, a group of related chemicals, or a complex mixture. Some substances are generally excluded from TSCA, including but not limited to, food, drugs, cosmetics and pesticides. TSCA addresses the production, importation, use and disposal of specific chemicals including polychlorinated biphenyls PCBs , asbestos, radon and lead-based paint.
The Federal Register Notices listed below include PCB-related rules proposed and final , notices of public meetings, responses to official comments, etc. This is not a comprehensive list of current regulations. Petition for Exemption. However, it is possible that PCBs may be incidental contaminants in listed hazardous waste e. In these cases, wastes that otherwise meet a listing criteria or are characteristically hazardous are still subject to RCRA regulation regardless of PCB content.
Section States may also have a regulatory program which is more stringent or broader in scope than the Federal program. Many state have expanded their universe of regulated wastes to cover additional waste e. Individuals should check with their state to see if they are subject to any state requirements.
EPA updated and clarified several sections of the PCB regulations associated with the manifesting requirements. The comment period closed November 5, No adverse comments on the rule were received, so the direct final rule took effect December 5, EPA issued this direct final rule to update and clarify several sections of the PCB regulations associated with manifesting requirements.
This update streamlined regulations for the safe management of PCBs making it easier for industry to understand and follow PCB manifest regulations. Since the promulgation of the PCB manifest regulations, several updates have been made to the RCRA manifest regulations where the corresponding changes have not been made to the PCB manifest regulations.
PCB waste handlers and generators must also adhere to the more recent RCRA hazardous waste manifest regulations, while still accounting for certain unique PCB manifest regulations.
This does not include the exemption to manifest waste transported on a right-of-way 40 CFR Like the other changes in this rule, explanations for the changes below are included in the subsequent sections in this direct final rule. Skip to main content. Polychlorinated Biphenyls PCBs. Contact Us. Due to their non-flammability, chemical stability, high boiling point and electrical insulating properties, PCBs were used in hundreds of industrial and commercial applications including: Electrical, heat transfer and hydraulic equipment Plasticizers in paints, plastics and rubber products Pigments, dyes and carbonless copy paper Other industrial applications Inadvertent PCBs In the United States, PCBs were commercially manufactured from until production was banned in by the Toxic Substances Control Act TSCA.
Products that may contain PCBs include: Transformers and capacitors Electrical equipment including voltage regulators, switches, re-closers, bushings, and electromagnets Oil used in motors and hydraulic systems Old electrical devices or appliances containing PCB capacitors Fluorescent light ballasts Cable insulation Thermal insulation material including fiberglass, felt, foam , and cork Adhesives and tapes Oil-based paint Caulking Plastics Carbonless copy paper Floor finish The PCBs used in these products were chemical mixtures made up of a variety of individual chlorinated biphenyl components known as congeners.
Release and Exposure of PCBs Today, PCBs can still be released into the environment from: Poorly maintained hazardous waste sites that contain PCBs Illegal or improper dumping of PCB wastes Leaks or releases from electrical transformers containing PCBs Disposal of PCB-containing consumer products into municipal or other landfills not designed to handle hazardous waste Burning some wastes in municipal and industrial incinerators PCBs do not readily break down once in the environment.
What new regulations are involved in this change? Language on non-empty containers and residues is not relevant to PCB waste. The facility must send the waste to another facility or back to the generator within 60 days of the rejection. While making arrangements for the rejected waste, the facility must ensure that the transporter retains custody or the facility provides secure, temporary custody of the waste.
Contact Us to ask a question, provide feedback, or report a problem. Manifesting exemption for the transport of waste on a public or private right-of-way within or along the border of contiguous property.
A retrospective study found statistically significant increased liver cancer mortality rates among the males compared to national liver cancer mortality rates [Kuratsune et al. A retrospective mortality study of Yu-Cheng cases found no statistically significant increased mortality from liver and intrahepatic bile duct cancers [Hsieh et al.
Before the comprehensive study conducted by Mayes et al. The Mayes et al. Data from animal studies have shown that PCBs cause gastrointestinal tract tumors, hepatocarcinomas, leukemia, lymphomas, and pituitary tumors [ATSDR ]. The Working Group considered more than 70 independent epidemiological studies with informative data for carcinogenicity of PCBs in human beings.
Occupational and epidemiologic studies have suggested or demonstrated other adverse health effects from exposure to PCBs.
These health effects can involve the:. These neurological deficits were directly related to the frequency of fish consumption [Mergler et al. In the Yusho and Yu-Cheng populations, the immunosuppressive effects of PCB exposure were associated with an increased incidence of persistent respiratory infection and enhanced responsiveness to mitogens [Guo et al.
Appetite loss has been reported in transformer and electrical equipment manufacturing workers exposed to various PCB-containing mixtures. Other nonspecific gastrointestinal symptoms experienced by workers exposed to PCBs include nausea, epigastric distress and pain, and intolerance to fatty foods [Emmett et al.
A recent study has indicated that several PCB metabolites induce gene mutations, chromosome breaks, chromosome loss and polyploidization in cells in culture and even provided the first evidence that a PCB congener is mutagenic in vivo [Robertson and Ludewig ].
Skip directly to site content Skip directly to page options Skip directly to A-Z link. Environmental Health and Medicine Education. Section Navigation.
Facebook Twitter LinkedIn Syndicate. Minus Related Pages. On This Page. Learning Objective. Upon completion of this section, you will be able to Describe adverse health effects associated with exposure to PCBs. Occupational exposure to PCBs can result in a broad spectrum of effects that includes Increased levels of some liver enzymes, with possible hepatic damage, Chloracne and related dermal lesions, and Respiratory problems [Alvares et al.
In animal studies, commercial PCBs elicit a broad range of toxic responses including: Acute lethality, Body weight loss, Carcinogenesis, Dermal toxicity, Fatty liver, Genotoxicity, Hepatomegaly, Immunosuppressive effects, Neurotoxicity, Porphyria, Reproductive and developmental toxicity, Thymic atrophy, and Thyroid hormone-level alterations.
This adverse health effects section addresses PCBs as a whole. Mechanism of PCB Toxicity. Dermatologic Effects. Key Points. Conclusive evidence that exposure to PCBs induces adverse dermal effects in humans exists. A typical dermal sign of exposure is chloracne.
Reproductive and Developmental Effects. Developmental effects in this population included statistically significant decreases in Gestational age 4. At four years of age, these children still had deficits in Weight gain, Depressed responsiveness, and Reduced performance on the visual recognition-memory test. At 11 years of age, the children of highly exposed mothers were Three times more likely than controls to have low full-scale verbal IQ scores, Twice as likely to lag behind at least 2 years in reading comprehension, and More likely to have difficulty paying attention [Jacobson JL et al.
Reproductive function may be disrupted by exposure to PCBs. Neurobehavioral and developmental deficits have been reported in newborns exposed to PCBs in utero. Endocrine Effects. These findings are dependent on the: Specific type of analysis for exposure to PCBs, Age of the cohort, and Specific exposure scenario [Emmett et al. The epidemiological studies suggest a link between exposure to PCBs and thyroid hormone toxicity in humans.
Studies in animals provide evidence of thyroid hormone involvement in the mechanism of PCB toxicity. Hepatic Effects. Liver effects characteristically include Fat deposition, Fibrosis, Hepatic microsomal enzyme induction, Increased serum levels of liver-related enzymes indicative of possible hepatocellular damages, Liver enlargement, and Necrosis [ATSDR ]. Although liver damage is common in animals exposed to PCBs, overt hepatotoxicity is uncommon in humans. Exposure to PCBs can increase serum levels of hepatic enzymes and can induce microsomal enzyme function.
Carcinogenic Effects. Epidemiologic studies have raised concerns about the potential carcinogenicity of PCBs. The report pointed out that PCBs alone or in combination with other chemicals could be associated with increased risks for Liver or biliary, Stomach, intestinal, and Thyroid cancers [Mallin et al. Other Effects. These health effects can involve the: Cardiovascular, Gastrointestinal, Immune, Musculoskeletal, and Neurological systems.
0コメント