PFOA, used in making Teflon, has been linked to cancer in lab animals, and Parkersburg residents had over five times more of it in their blood than the national average. Hit with a $10.25 million fine from the EPA two years earlier, DuPont had pledged to reduce its PFOA emissions. For her junior-year science fair project, Welcker decided to see if the company was making good.
At first it was. But four months after Welcker began her tests, PFOA levels began to rise. Welcker went on local TV to warn neighbors and teach them an easy trick for testing their water at home: "Just boil it and shake it," she'd say. If it bubbled, it meant PFOA was present. In her backyard laboratory, she built a device using windshield wipers, steel wool, and a six-volt battery that harnessed electricity to remove the acid from water through a process called electrosorption. She earned a patent for her invention, and some unforeseen notoriety. A documentary film crew caught wind of Welcker's research, and while shooting footage at the DuPont plant with Welcker in tow, raised suspicions of espionage that led an FBI agent to the Welckers' door. Filming a chemical plant, he said, is a breach of homeland security. Welcker was stunned. "I'm not attacking DuPont," she protested to her parents. "I'm helping them!"
Since then the company has cut emissions drastically and no longer considers Welcker a security threat. For her part, between studying chemistry at West Virginia Wesleyan College and applying to med school, Welcker still finds time to go home each month and test the waters.
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