tap water chemical USA map
In a study released by the US Geological Survey (USGS) on Wednesday, harmful per- and polyfluorene alkyl substances (PFAS) are estimated to contaminate at least 45 percent of drinking water in the United States, with most of the concentration near urban areas.

According to the USGS, PFAS are synthetic chemicals used in a wide array of commonly used items such as non-stick pans, fire extinguisher foam, food packaging products that are grease resistant, and more. They take a long time to break down and are commonly referred to as "forever chemicals."

The study tested 716 different locations across the country and found about 75 percent of tap water in urban areas and 25 percent of rural areas with PFAS tested in the tap water. There are over 12,000 types of PFAS, and the study only tested 32 of them as not all can be detected with current tests. Areas with higher concentrations include the Great Plains, the Great Lakes, the Eastern Seaboard, and Central and Southern California.

PFAS tapwater chemicals map
"USGS scientists tested water collected directly from people's kitchen sinks across the nation, providing the most comprehensive study to date on PFAS in tap water from both private wells and public supplies," the study's lead author, hydrologist Kelly Smalling, said. "The study estimates that at least one type of PFAS - of those that were monitored - could be present in nearly half of the tap water in the U.S. Furthermore, PFAS concentrations were similar between public supplies and private wells."

According to the US Environmental Protection Agency (EPA), most people in the United States have been exposed to PFAS which may lead to a variety of health complications. These include a decrease in fertility, developmental effects in children, an increased risk of some cancers, an increase in cholesterol levels, and possible issues with the body's natural hormones.

The EPA has developed several action plans to reduce PFAS exposure in the US, including using $2 billion from the Bipartisan Infrastructure Law passed in February, to promote access to clean drinking water in disadvantaged communities.