Polychlorinated Biphenyl. (CPB's). Jessica MacDonald Bio 2A: Environment and Human Health 5/04/05. What Are PCB’s?. Mixtures of up to 209 individual chlorinated compounds (known as congeners).
Polychlorinated Biphenyl (CPB's) Jessica MacDonald Bio 2A: Environment and Human Health 5/04/05
What Are PCB’s? • Mixtures of up to 209 individual chlorinated compounds (known as congeners). • PCB’s are a fat-soluble, water-insoluble hydrocarbon containing 1 to 10 chlorine atoms. • Common Structure C12H10-xClx: • PCB mixtures are known in the U.S. by the trade name Aroclor.
Polychlorinated Biphenyl • PCB’s are either oily liquids or solids, some exist as a vapor in air. • Colorless to light yellow • PCB’s have no smell or taste • Extremely stable, withstanding temperatures of up to 1,600°F (870°C). • PCB’s are fire-resistant and an electrical insulator.
Uses of PCB’s • PCBs were used in heat-transfer, lubricants and insulation fluid in cooling systems and electrical equipment. • Also used in sealants, rubber,paints, plastics, printing ink and insecticides. • Products including old fluorescent lighting fixtures and electrical devices and appliances, such as television sets and refrigerators made before 1977 may contain PCBs. • Manufacture of PCBs was stopped in the U.S. in 1977 because of evidence showing large amounts in the environment can cause harmful health effects.
PCBs in the Environment • PCBs entered air, water and soil during their manufacture, use and disposal. • Accidental spills and leaks during their transport, and from leaks or fires in products containing PCBs. • Still released from hazardous waste sites; illegal or improper disposal of industrial waste; leaks from old appliances. • PCBs are not readily biodegradable • In water, stick to organic particles and bottom sediments; binds strongly to soil. • PCBs are consumed by small organisms and fish in water.
Exposures to PCBs • Using old fluorescent lighting fixtures and electrical devices and appliances, that are over 30yrs old. • Eating contaminated food (fish, meat, and dairy products) • Breathing air near hazardous waste sites and drinking contaminated water. • Workplaces during repair and maintenance of PCB accidents, fires or spills involving products containing PCB.
Health Affects Caused by PCBs High dosage: • Skin conditions such as acne and rashes. • Changes in blood and urine, indicating liver damage. Animals (eating high amounts/short time): • Mild liver damage; some death Animals (eating small amounts/long time): • Anemia • Skin conditions • Liver, stomach and thyroid glad injuries. • PCBs are not known to cause structural birth defects.
PCBs Affect on Children • Mothers exposed to high levels of PCBs in the workplace or ate large amounts of contaminated fish: • Babies weigh less than others babies with mothers not exposed to PCBs. • Problems with motor skills and decreased short term memory. • Immune system complications • Infants most likely exposed through breast milk.
Can PCBs Cause Cancer? • Studies show, workers exposed to high doses of PCBs can develop certain kinds of cancers including liver and biliary tract cancer. • Rats that ate food with high doses of PCBs for two years developed liver cancer. • The EPA and the International Agency for Research on Cancer (IARC) have determined PCBs to be carcinogenic to humans.
Reduce the risk of exposure to PCBs • Avoid eating the fish and fish-eating wildlife that have been issued advisory warnings about PCB-contamination. • Avoid children playing with old appliances, electrical equipment, or transformers that might contain PCBs. • Discourage children from playing in the dirt near hazardous waste sites, eating dirt and putting dirty hands, toys and other objects in mouth. • If exposed to PCBs in the workplace, they could be brought home on clothes, body or tools. Shower before leaving; keep work clothes and tools separate from clean items.
Government Recommendations • The Environmental Protection Agency (EPA) has a limit of 0.0005 mg of PCBs pr liter of drinking water. • Spills and accidental releases of 1 pound or more of PCBs into the environment must be reported to EPA. • FDA requires infant food, dairy products, fish and shellfish, poultry and red meat contain no more than 0.2-3 parts of PCBs per million parts of food. • Many states have established fish and wildlife consumption advisories for PCBs.
Current Issues with PCBs Austin, Texas: State health officials urge people to limit their consumption of speckled trout from the Houston Ship Channel and Upper Galveston Bay, due to high doses of PCBs. • The area covered is 33 square miles of a 600-square-mile bay radius. • PCB levels in the sampled specked trout averaged 0.140 ppm and as high as 0.380 ppm (PCB levels in fish above 0.047 ppm may cause health risks. • Adults being advised to eat only 8 ounces per month • Allow catching the fish has not been prohibited because it is not sold in restaurants or stores.
Seafood and aquatic life specialist with the health agency, stated that black drum, red drum, flounder and speckled trout were tested for PCBs and several other contaminants. • Only health risk found was PCBs in speckled trout. Different species of fish and affected in different ways. • Texas Parks and Wildlife Department states that it is a concern but not a panic, but an issue for the people trying to catch diner.
Current Issue with PCBs Money • Costing $2.7 million to clean-up PCB from former Baldwinville Products Paper Mill (Ma). • Including cost of workers, machinery and specialists, along with PCB treatment. • Soil thermal desorption, heat to point of cooking not burning. Drives PCB off as gas into liquid form, than captured and disposed of safely.
Current Issue with PCBs • Studies done at the University of Rochester have linked PCBs to Parkinson’s disease- a progressive neurological disorder that affects about 1% of Americans over 60. • PCBs degrade nerve pathways associated with Parkinson’s. • Exposure caused by PCBs found in the food chain, inhaled, and an additive in pesticides.
Medical Tests • Medical tests exist to check the level of PCBs in your blood, body fat and breast milk. • These test are not routinely done • Most people contain small amounts of PCBs because everyone has been environmentally exposed to PCBs. • Allow test can determine the amount of PCBs present the cannot tell how long you were exposed or if health risks will develop.
Additional Information The Agency for Toxic Substances and Disease Registry (ATSDR) • Environmental Health Clinics to exam and answer questions about PCB illnesses The State Health and Environmental departments • Locate any contaminated waste and water sites in your area. Environmental Protection Agency (EPA). • Find out the legal amount of PCBs permitted.