PCBs 101: Understanding Polychlorinated Biphenyls
Polychlorinated biphenyls, or PCBs, are man-made organic chemicals originally used for various industrial and consumer applications. As the name suggests, these chemicals are composed of carbon, hydrogen, and chlorine, varying in structure. The location of the chlorine atom(s) determines the physical and chemical properties of the material, and thus its use.
PCBs were first made in the United States in 1929. They often appear clear to light yellow in color and are oily liquids or wax-like solids. This family of chemicals was revered for its nonflammable, stable, and insulating properties. PCBs remained in production until they were banned in the United States by the Toxic Substance Control Act in 1979 due to their suggested link to cause adverse health effects to both humans and the environment.
Where are PCBs found?
PCBs are most often found in the following materials:
- Electrical transformers and capacitors
- Voltage regulators, switches and bushings
- Oils used in some motors or hydraulic systems
- Caulking
- Fluorescent light ballasts
- Oil-based paints
- Thermal insulation materials
A total of 209 PCB congeners exist in the production of these various materials. Congener in this case means a related molecule. Each will vary based on the number and location of chlorine atom(s) in the PCB molecule. While various trade names exist for each, the most common PCB mixture is called the Aroclor series. Other common trade names include Inerteen, Pyranol, and Askarel.
Who is affected by PCBs?
PCBs can affect anyone, but those with the highest risk of PCB exposure include individuals who maintain capacitors or transformers built before 1977, along with firefighters and emergency response crews responding to an electrical system fire or a spill containing PCBs. Notably, the risk of exposure can be greatly mitigated with the use of personal protective equipment (PPE).
In addition to occupational exposure, environmental interactions affect people worldwide and are more common. PCBs make their way into the environment by poor waste management and accidents resulting from incidental releases. Other times, they are released from transformers due to improper recycling or mishandling by those trying to extract the copper transformer core. Once they find their way into the environment, they are extremely persistent. With their longevity, they can cycle from air, to water, to soil over and over as they spread across the globe. They have even been detected in the wildlife in the Arctic!
How are we exposed to PCBs?
We have all likely been exposed to PCBs in one form or another. Exposure can occur through the following four routes:
- Ingestion – Ingestion can occur from eating or drinking contaminated food or beverages. One of the most common food sources that is affected by bioaccumulation of PCBs, or the gradual increase in chemical levels in an organism over time, is fish. In a fish-eats-fish world, organisms higher up in the food chain accumulate more of these toxins in their environment such as PCBs, DDT, and mercury. Larger fish, as well as those with high fat content, present the highest risk, such as tuna, shark, swordfish, mackerel, and wild salmon.
- Adsorption – Exposure can also result from adsorption on your skin if you were to be splashed with PCB oil. These oils are frequently found in old transformers or ballasts, and once exposed, PCBs are stored in your fatty tissue.
- Injection – Injection of PCBs could occur from sustaining a cut from a contaminated material such as an old fluorescent light ballast.
- Inhalation – PCB particulate matter can be inhaled from indoor air in schools, offices, and homes that hold older PCB-made items, including caulk, fluorescent light ballasts, and insulation. Exposure can also occur by inhaling PCB-impacted soil transported by the wind.
Why do PCBs need to be abated?
PCBs must be properly managed and disposed to limit environment impact and prevent adverse health effects.
Animal studies have linked PCB exposure to adverse health effects with the immune system, reproductive system, nervous system, endocrine system, and other specific organs. Human exposure has been linked to possible carcinogenic effects in addition to negative implications to other organ systems.
For these reasons, effective abatement processes must be taken to eliminate or minimize the exposure to PCBs.
PCB abatement assistance
For more information on PCB abatement, reach out to EnviroServe today. Our Team specializes in “where you need us, when you need us” waste management, emergency response, and environmental remediation services. Contact (800) 488-0910 for all your environmental needs!