Polychlorinated biphenyls (PCBs) haven't been legally manufactured in the U.S. since the late 1970s, but they break down so slowly in the environment that they can still turn up in water supplies near older industrial sites and contaminated soil or sediment decades later.
The EPA regulates PCBs at a Maximum Contaminant Level of 0.0005 mg/L (0.5 parts per billion), with a Maximum Contaminant Level Goal of zero. Their manufacture was banned in the United States under the Toxic Substances Control Act, but PCBs were widely used for decades before that in electrical equipment, insulation, and industrial processes — and because they resist breaking down naturally, they persist in soil, sediment, and groundwater near older industrial and manufacturing sites long after the source equipment is gone.
PCBs are classified by the EPA as a probable human carcinogen, and exposure isn't something you can detect by taste, smell, or appearance — a lab water test is the only reliable way to know your level.
Illustrative water-testing concept.
Watch For This
Signs to Look For
A property near a former industrial, manufacturing, or electrical-equipment site
Known soil or groundwater contamination in your area (check your local environmental agency's records)
No reliable taste, smell, or color indicator at any level — testing is required
An older well with no recent comprehensive water test
How We Fix It
Reverse Osmosis System
Reverse Osmosis System
Reverse osmosis filtration is effective at reducing PCBs and similar legacy industrial compounds from drinking water, giving you a dependable barrier even decades after the original contamination source.
Note: this is addressed by our reverse osmosis drinking-water system specifically — our whole-house filtration systems are not designed or certified to remove it.
Curious What's In Your Water?
We'll test it for free and show you exactly what a system would remove.
The Maximum Contaminant Level is 0.0005 mg/L (0.5 parts per billion), with a goal of zero.
No — their manufacture has been banned in the U.S. for decades. They persist in water supplies because they break down very slowly in soil and sediment, not because they're still being produced.
No, not without testing. There's no taste, smell, or visible sign at any level — a lab water test is the only way to know.
