• Health

How to Find Out If Your Drinking Water Is Safe

3 minute read

A recent study found that millions of Americans are consuming water from a public supply contaminated with dangerous levels of polyfluoroalkyl and perfluoroalkyl, otherwise known as PFASs.

Though not all of their potential effects are known, these industrial chemicals have been linked to various medical conditions like high cholesterol, obesity, hormone suppression, and cancer. Effects may not be noticeable for some people, but certain aspects, including timing of puberty, could compound the potential risks.

Unfortunately, these chemicals are everywhere—in food packaging, fabrics, nonstick cooking pans, and firefighting foams. As a result of their pervasiveness, they eventually find their way into our water supply.

The study, published in the Environmental Science & Technology Letters journal found that 16.5 million Americans consume water from public supplies containing one of six PFASs either at or above the maximum limit recommended by the Environmental Protection Agency.

The water supplies are found in 33 states, American Samoa, Northern Mariana Islands, Guam, and the Salt River Pima-Maricopa Indian Community. The 13 states with the highest frequencies and concentrations are California, New Jersey, North Carolina, Alabama, Florida, Pennsylvania, Ohio, New York, Georgia, Minnesota, Arizona, Massachusetts, and Illinois.

Your local water supply is more likely to be contaminated if you live near an industrial site that manufactures PFASs, a military fire training area, or a wastewater treatment plant, according to the study. Groundwater tends to be more contaminated than surface water.

To find out if your local water supply does contain PFASs in excessive amounts, the EPA says your county health department may help you test it. If your local department doesn’t provide that service, you should instead contact a state-certified laboratory. You can find one in your area by calling the Safe Drinking Water Hotline at 800-426-4791 or visiting www.epa.gov/safewater/labs.

According to the Green Science Policy Institute, simply boiling water doesn’t eliminate contaminants. If your local water supply is contaminated with PFASs, you could drink and cook with bottled water, though that’s not a particularly viable—or cheap—solution.

Alternatively, there are granular activated carbon filters or reverse osmosis water treatment devices that could reduce the level of chemicals in your drinking water, though the effectiveness of those devices haven’t been established.

According to the EPA, PFASs aren’t as commonly manufactured as they were 15 years ago. Between 2002 and 2004, the primary manufacturer of these chemicals phased them out of production, and in 2006 eight major companies agreed to phase them out as well, though the agency does state that “there are a limited number of ongoing uses.”

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