Ever since the US started churning out per- and polyfluoroalkyl substances (PFAS) in the 1940s, these long-lived toxic chemicals have been accumulating everywhere humans have trodden.
Since then, these compounds have leached from industrial facilities and trash systems into our waterways, making our drinking supply one of the main ways forever chemicals are getting into our bodies.
If you’re now eyeing your glass of water suspiciously, know that there are steps you can take to find out if there are PFAS in that H2O, and lower the risk of exposure for you and your family.
Your water might have PFAS
Between 2016 and 2021, the US Geological Survey sampled the water from 716 different taps across the country and found that an estimated 45 percent of tested sites contained at least one kind of forever chemical. The study is the broadest of its kind in the US, making its main finding the best risk estimate we have for PFAS contamination in our drinking water.
While efforts to regulate these chemicals are gaining traction, there is no federal mandate limiting the amount of PFAS in our drinking supply. In March, the Environmental Protection Agency proposed a nationwide enforceable limit of four parts per trillion for each of the six types of PFAS in our drinking water. But while the EPA weighs public comments on the bill, millions of people might still exposed to these persistent pollutants, as not all public water systems in the country are required to monitor and remove them.
[Related: ‘Forever chemicals’ detected in paper and plastic straws]
Even if the EPA’s proposal succeeds, imposing legal PFAS limits doesn’t necessarily mean our water will be safe to drink. For example, the EPA’s maximum contaminant level goal for perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), the most notorious cancer-causing PFAS, is zero.
For these two compounds, “there’s no known safe level,” says Kelly Smalling, a USGS environmental chemist and lead author of the national tap water study.
Researchers are still looking into how forever chemicals impact our health and how to efficiently dispose of them. This is particularly important because there are vast geographical areas in the US where PFAS levels are high enough to pose a health risk over time, but low enough to make it hard to remove them from the environment.
By understanding the risk of PFAS exposure in your drinking water, you can find the best prevention strategy to mitigate it accordingly.
Know thy water source
The easiest step in understanding your risk of PFAS exposure is knowing where you get your water from, says Jamie DeWitt, a pharmacologist at East Carolina University. If it comes from a public supply, you have it easier than those getting their H2O from private wells, as utility companies have to regularly test for contaminants and report the results to the public.
The Environmental Working Group, an advocacy non-profit, has a nifty online tap water database that shows the servicing utility and contaminants detected where you live—just search using your zip code. You can also use this platform to gather information before you talk to your public water provider, which the EPA encourages you to do. If you find high PFAS levels in your water supply, DeWitt recommends you reach out and find out what your utility company is doing to reduce them.
There’s a caveat, though—the data included in the EWG’s database are of contaminants tested by and at the utility plant, which are a few steps removed from the actual amount that you might imbibe at ho