Nearly 50% of tap water samples in the US contain toxic chemical levels that exceed thresholds.

According to Reuters , the US Geological Survey (USGS) tested tap water samples from more than 700 residences, businesses and water treatment plants across the United States for perfluoroalkyl or polyfluoroalkyl chemicals, or PFAS.

At least one of these two synthetic chemicals — often referred to as “forever chemicals” — was detected in 45 percent of samples at levels that exceeded U.S. standards and proposed regulations, the researchers said.

PFAS are water-resistant, meaning they do not break down in the environment and persist in the human body for years.

Developed in the 1940s with the creation of Teflon, a non-stick coating for cookware, today they are used in everything from clothing to plastic products.

These substances pose serious health risks with long-term exposure. According to the US Centers for Disease Control and Prevention (CDC), exposure to high levels of PFAS can disrupt hormones, cause liver dysfunction, increase the risk of kidney or testicular cancer, reduce birth weight in infants, and affect the health of pregnant women.

Previous studies have measured PFAS in groundwater, reservoirs, and water treatment plants. But analyzing tap water allows for a more accurate assessment of what people are drinking, said USGS hydrologist Kelly Smalling, who led the study.

Today, published studies account for only a fraction of the 12,000 PFASs that exist, according to Reuters . The USGS samples were taken from public supplies and private wells between 2016 and 2021, and tested for 32 PFASs.

There was no difference in PFAS exposure between samples from private wells and public water supplies, which was “very surprising,” Smalling said.

Public water supplies are regulated by the US Environmental Protection Agency (EPA) while private wells are not.

Research shows that people in urban areas are at higher risk of exposure to PFAS in drinking water than those in rural areas.

In March, the EPA first proposed a national standard for six PFAS in drinking water, which would require public water systems to monitor and report when PFAS exceed limits.

Minh Hoa (reported by Tuoi Tre, Thanh Nien)

Source: https://www.nguoiduatin.vn/gan-50-mau-nuoc-may-tai-my-co-muc-hoa-chat-doc-hai-vuot-nguong-a616159.html