Polychlorinated Biphenyls (PCBs)

EPA Maximum Contaminant Level (MCL)

0.0005 mg/L

PCBs can often still be found in old power transformers.

PCBs are a group of organic chemicals formerly used in a wide range of industrial and commercial products until their United States ban 1979. Products that may contain PCBs include electronics, fluorescent light ballasts, insulation, paints, caulk, plastics and carbon-free copy paper.

PCBs arrive in water primarily through runoff from landfills and discharge from chemical waste.

Health Effects of PCBs

PCBs are carcinogens that can lead to a wide range of health problems. According to the EPA:

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Some people who drink water containing polychlorinated biphenyls well in excess of the maximum contaminant level (MCL) for many years could experience changes in their skin, problems with their thymus gland, immune deficiencies, or reproductive or nervous system difficulties, and may have an increased risk of getting cancer.

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Water Treatment for PCBs

The EPA recommends granular activated carbon (GAC) for the treatment of PCBs.

Sources: EPA, EPA (2), Photo: WikiMedia, author: Sturmovik