What Are 'Forever Chemicals'?

Per- and polyfluoroalkyl substances, known as PFAS or colloquially as “forever chemicals”, are a group of chemicals that do not easily break down in the Earth’s atmosphere or inside the human body. This persistence means they can accumulate over time and cause grave complications for human health, having been linked to liver damage, cancers and other problems, although their exact impacts are still not fully understood.

The manmade chemicals are especially prevalent in the USA, where they have been employed in a number of different industries since the 1940s. One unwanted consequence of that widespread use has been the contamination of drinking water supplies with the substances, which a recent report found extended far beyond previous estimates.

A history of PFAS

The so-called “forever chemicals” were first introduced over 70 years ago for use in a variety of different industries. Among others, they have been employed in the following areas:

• Household products, such as non-stick pans (those coated with Teflon, for example), cleaning products, paints, waxes, stain- and water-resistant fabrics and many others
• Food, including food that has been cultivated in PFAS-contaminated soil or water, processed with machinery that has come into contact with PFAS or packaged in containers made from the substances
• Industrial uses, such as in the foam used by firefighters, oil recovery facilities, chrome plating equipment and electronics manufacturing
• Utilities, for example in wastewater treatment plants and landfill sites

When the chemicals were first discovered, little thought was given to how they might affect human health in the long run, especially given their ability to endure over time. However, there has been a growing focus on analysis of PFAS concentrations in drinking water of late, sparking concerns that the problem might be more ubiquitous than previously imagined.

US supplies compromised

A previously unpublished report from the Environmental Protection Agency (EPA) had placed the number of Americans at risk from exposure to PFAS in their drinking water at 110 million. However, the latest study from the Environmental Working Group (EWG), a non-profit watchdog, claimed that figure was far too low. After analysing 44 different samples of tap water across the contiguous states, the researchers only found one site where PFAS were not present.

That was in Meridian in Mississippi, which relies on an unusually deep well located over 200m below ground level. Only two more, Seattle in Washington state and Tuscaloosa in Alabama, recorded levels of PFAS below one part per million, which is the threshold deemed safe by the EWG. Miami, New Orleans and Philadelphia were among the most contaminated sources tested.

Greater regulation needed

Thanks to great advances made in our ability to monitor water quality in drinking water networks, the EPA has been aware of the presence of PFAS in water supplies since the beginning of the millennium. However, they have yet to put in place a national limit on the concentration of PFAS allowable by law. Indeed, their own current recommended threshold is far higher than the one suggested by EWG at 70 parts per million.

Two years ago, the Department of Health and Human Services published a report which recommended that level should be made at least 10 times lower. Both the EPA and the White House did their utmost to suppress the report, and although they have since indicated they are working on implementing new limits for the chemicals, no timeline has been forthcoming.