This Region Of The US Was Riddled With "Forever Chemicals." They Just Discovered Why.

Worrying levels of "forever chemicals" were detected in the waters of certain pockets of North Carolina in recent years. These human-made pollutants appeared everywhere, from rivers and sewers to drinking water. Now, a new study may have uncovered the culprit.

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“Forever chemicals” is the nickname given to PFAS, a synthetic group of compounds added to everyday products to boost their waterproof, non-stick, and stain-resistant properties. They're commonly found in items such as non-stick cookware, fast food packaging, certain fabrics, firefighting foam, and even components of jet engines.

There are around 4,700 different chemicals in the PFAS family, some of which have been linked to serious health concerns. PFAS are incredibly persistent by design, which is bad news if they're damaging to health. They do not break down easily in nature or in the human body. Their chemical structure makes them resistant to heat, water, and oil, allowing them to accumulate over time in soil, water sources, wildlife, and human tissue. 

One such place where PFAS levels have been seen steadily creeping upwards is in the Piedmont region of North Carolina. The sewers in and around the city of Burlington showed that concentrations were up to 12 million parts-per-trillion, levels around 3 million times greater than those set by the Environmental Protection Agency.

To detect the mysterious source of the contamination, scientists at Duke University turned to a new method. Instead of looking for the chemical forms of PFAS that are routinely monitored, they tested for nanoparticle “precursors” of PFAS that degrade into the chemicals that current tests are designed to detect.

While PFAS precursors typically transform into these other forms very slowly, Burlington’s unique wastewater treatment practices were accelerating that transformation. Weirdly, tests revealed far higher levels of PFAS leaving the wastewater facility than entering it, indicating that PFAS precursors were being converted during the treatment process.

At the time, the Burlington area was using a special technique that applies heat and pressure to break down complex organic compounds. It turned out that the same process was transforming PFAS precursors into fully fledged PFAS. 

“As soon as they shut that process off, the measurable PFAS levels in the wastewater came way down,” Lee Ferguson, lead researcher and professor of civil and environmental engineering at Duke University, said in a statement. “But the precursors were still coming into the facility and being concentrated into sludge that is eventually spread on agricultural fields, where they will transform to more soluble, mobile, and toxic forms of PFAS over time. We needed to find the source.”

Through further snooping, the team was led to a source: the wastewater of a textile manufacturing plant in the region. Through the processing of materials, PFAS precursors were being washed into drains, eventually contaminating local waterways and drinking supplies.

“After turning all the available PFAS precursors into measurable forms of PFAS, the levels in one textile manufacturer’s wastewater jumped 50,000 to 80,000 percent,” Faught said. “I jumped out of my chair when I saw the results. It’s the most dramatic result I’ve ever seen in my lab. It contaminated all of our instruments for over a week,” he said. 

“Every system downstream of that facility is also now seeing a significant drop in the amount of PFAS in their drinking water,” Ferguson continued.

The researchers believe their detective work could help communities worldwide identify the roots of their own PFAS problem — and underscore how elusive and complex these pollution sources can be.

“We have some of the most sophisticated instruments in the world for PFAS analysis, and we couldn’t detect these until we dramatically changed our approach. Sometimes we don’t know what we don’t know, and there is a lesson to be learned about blind spots in our analyses when it comes to looking for new PFAS in the environment,” added Ferguson.

The new study is published in the journal Environmental Science & Technology Letters.