By Sara Hamidovic
Polychlorinated biphenyls (PCBs) were produced commercially in the United States between 1929 and 1979. It is estimated that 600,000 tons were produced in the U.S. alone. PCBs were determined to be toxic as early as 1940 based on industrial incidents involving injury to workers – today they are suspected to cause cancer. Manufacturing of PCBs peaked in the 1960s and in 1973 the use of PCBs was banned, except in totally enclosed systems. Congress banned production of PCBs in the U.S. in 1979 to prevent further environmental contamination.
PCBs were mass produced in numerous applications due to desirable chemical properties including low flammability, electrical insulation and chemical stability. These properties were crucial in insulating fluids and coolants in transformers, capacitors and electric motors. The widespread use of PCBs in countless products resulted from how well PCBs do their job. After the ban, commercial manufacturers were faced with the challenge of finding a PCB replacement that works as well with less risk to the environment.
Many of the chemical properties that make PCBs desirable in commercial applications make them harmful in the environment. High chemical stability prevents PCBs from breaking down – they hang around for a long time. They are hydrophobic and lipophilic, meaning that they do not dissolve in water, but readily dissolve in fats. PCBs are denser than water – they sink. These tendencies cause PCBs to sink to the bottom of a body of water and cling to the sediment; therefore, wherever the sediment goes, the PCBs go.
Bottom feeding animals are generally where PCBs enter the food chain. Each time a large fish eats a smaller fish that is contaminated with PCBs, the concentrations in fat deposits are passed upward. Contamination passes to the critters at the top of the food chain – water birds, bears, humans, etc.
While this is all interesting, you are probably wondering “how does this apply to me and my facility?” Good question! There are a range of answers based on how your yard operates and what you have for inventory. Let’s divide recyclers into three categories for purposes of explanation. If you are buying only late model cars (insurance auctions, rebuildables, etc.), Category 1, you do not have much to worry about concerning PCBs. If you are a yard that purchases late and early model cars, Category 2, you may have inventory (manufactured pre-1973) that contains small amounts of PCBs. If you are a scrap processor that purchases scrap metal for recycling, Category 3, you are likely to come across materials that contain PCBs – potentially in large quantities and at high concentrations.
PCBs are Workhorses.
They are second to none as insulators. The list of products that contain PCBs is long and distinguished: insulating fluids, fluorescent lights, paints, cements, polyvinyl chloride (PVC) electrical wire coating, pesticides, cutting oils, lubricating oils (transmission fluids), hydraulic fluids, sealants (grain silo and windshield sealants), window caulking, de-dusting agents, water-proofing compounds, adhesives, wood floor finishes, vacuum pump fluids, carbonless copy paper, insecticides, resins, gaskets and roofing materials. The bolded products are what Category 2 may come in contact with in vehicles predating the legislation of 1973 that prohibited use of PCBs in open systems. Most of the products listed above could reasonably show up in Category 3.
For those of you in Category 2, an open system is one such as window caulk or electrical wire coating where the PCBs are not encapsulated and are able to escape as the product breaks down. While concentrations of PCBs in these products was often quite high, quantities of these products is relatively low (there is only so much windshield sealant and electrical wiring in a car). Be aware of your inventory. Minimize the risk of releasing PCBs to the environment by handling old cars gingerly – don’t shatter the windshield, don’t leave wires laying on the ground and ensure you have the appropriate secondary containment when the vehicle is crushed.
For those of you in Category 3, train your employees on PCB component identification, handling, storage and disposal, and carefully inspect incoming materials. Informing employees of what items are likely to contain PCBs can greatly reduce the risk of PCB contamination on your yard. The items that are most likely to contain large quantities of PCB contaminated oil are closed systems such as capacitors (contained in white goods), hydraulic systems and electric motors. PCB capacitors were generally encased within a soldered or welded metal case. Newer PCB free capacitors often had a plastic case. The U.S. Environmental Protection Agency (USEPA) required that all non-PCB capacitors produced between July 1, 1978 and July 1, 1998 be labeled “No PCBs.” If an item appears older than 1998 and there is not a “No PCBs” label, research the origin, use and contents before you buy it. If you do buy a PCB containing component handle it appropriately.
PCBs are nasty.
A little bit of PCB contamination goes a long way and allowable concentrations on PCBs in the environment are extremely low. You have heard of gifts that keep on giving – PCB contamination is one. Not only is PCB contamination extremely expensive to dispose of, there is a stigma associated with PCB contamination that is very hard to live down. For profitability of your business it behooves you and your people to be knowledgeable about PCB component identification. One large component containing PCBs, if handled improperly, can cause contamination that could cost significantly more to clean up than you stand to make from the metal.
I urge you to protect your business by educating yourself about PCB containing materials, proper handling, storage and disposal. If you do not know the answer to a question, there are environmental professionals that can help you. Train yourself and your employees, then hold them to a high standard of care. As always, if you have any questions or would like any further information, please do not hesitate to contact VET at (812) 822-0400.
Sara Hamidovic is President/Principal Engineer of VET Environmental in Bloomington, Indiana. She is a Licensed Professional Engineer (PE) in the State of Indiana and a Certified Hazardous Materials Manager (CHMM). She graduated from the U.S. Military Academy at West Point in 2004 and served as an engineer officer in the Army until 2009. While in the Army, she completed a two-year tour in Iraq with the 54th Engineer Battalion (Combat Mechanized). Sara also has a Master’s degree in Environmental Science from Indiana University’s School of Public and Environmental Affairs.