"Forever chemicals" and cancer

Jun 13, 2023

How to identify and reduce exposure to PFAS

“Forever chemicals”— perfluoroalkyl and polyfluoroalkyl substances also known as PFAS – are widely used, long-lasting compounds that take a very long time to decompose. They are in products that resist water, stains and heat, and have been improving familiar consumer goods since the 1940s. Famously, PFAS were key to the original formula for non-stick Teflon pans.

Today, “forever chemicals” are found in everything from toilet paper to plastic and paper food containers to fruit juice. PFAS are in firefighting foam and turnout gear; shampoo, sunscreen, hair dyes and many (many) kinds of make-up.

Unfortunately, while “forever chemicals’’ help to enhance modern life as we know it, they also pose serious toxic risks to public health safety and the environment — specifically through the increasing contamination of our public water supplies. Contamination of our drinking water may be related to adverse reproductive and developmental outcomes, and some cancers. A recent study found that PFAS levels in New York State tap water are more than twice the amount allowed by current national EPA guidelines and affect nearly 3.2 million New York residents.

“Studies in populations exposed to PFAS contaminated water have identified increased cholesterol levels, changes in liver enzymes, changes in thyroid hormones, difficulties in becoming pregnant, high blood pressure during pregnancy, low birth weight and developmental delays, weak reaction to vaccines, kidney cancer and testicular cancer to be higher in these populations compared to the general public,” advises Kirsten Moysich, PhD, Professor of Oncology, Cancer Prevention & Control at Roswell Park Comprehensive Cancer Center.

PFAS has been generically classified as a possible, but not an official, carcinogen. Researchers, however, are identifying mechanisms in “forever chemicals” that may lead to cancer.

“Biological mechanisms by which PFAS could potentially be linked to the development of human cancers include the disruption of cell metabolism and immune function, epigenetic changes, including damage to DNA not caused by mutations, and the disruption of hormone levels in the body,” Dr. Moysich says.

“The strongest epidemiological evidence shows that kidney and testicular cancers are associated with higher levels of PFAS. Weaker evidence exists for prostate cancer, and studies of other cancers have been largely inconsistent or provided no indication of an association.”

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Most recently, a study has linked PFAS and contact lenses. Researchers tested 18 different contact lenses for PFAS found that 100% of popular products came back with various levels of organic fluorine, a key indicator of “forever chemicals.”

More than 45 million people today wear contact lenses, and 90% of these wearers — two-thirds of whom are female — use soft, disposable contacts. The presence of “forever chemicals” inside contact lenses and contact lens products has raised concern about their safety and potential connection to the onset of eye diseases, including eye cancer.

“This is a difficult link to establish in humans because cancers of the eye are very rare, and there are no epidemiological data that would point to contact lens use and eye cancers,” says Dr. Moysich.

There are currently more than 12,000 types of “forever chemicals” — toxic at even their lowest levels — that accumulate and persist in the human body and the environment for long periods of time. The National Academies of Science has pronounced PFAS a serious public health threat both at home and worldwide. In March 2023, the U.S. Environmental Protection Agency proposed its first federal limits on PFAS to improve the safety of drinking water. The proposed legislation is intended to reduce PFAS exposure for nearly 100 million Americans and potentially decrease cancer rates, heart attacks and birth complications.

While “forever chemicals” are more or less everywhere in our modern lives, there are a few steps you can take to reduce their toxic long-term effects. These include installing carbon filters or reverse osmosis systems to reduce PFAS in drinking water and avoiding eating fish caught in PFAS-contaminated water.

“Avoid eating food grown or raised near places that used or made PFAS, avoid eating food packaged in material that contains PFAS, and avoid using stain-resistant carpeting and water-repellent clothing,” advises Dr. Moysich recommends.

To determine if something contains PFAS, look for ingredients that include the words "fluoro" or "perfluoro." Other tips for determining if a product contains “forever chemicals” include:

“We live in a modern world that provides many convenient advantages, but also comes with the price of exposing us to a wide variety of chemicals, such as PFAS. If people are worried about a relatively modest link to kidney and testicular cancers, they can engage in steps to reduce their exposure, as described in this blog,” says Dr. Moysich.

“However, people should worry about avoiding alcohol and tobacco, eating a healthy diet and exercising. These lifestyle behaviors are much, much more strongly linked to all kinds of cancers and chronic diseases than exposure to PFAS.”