{"id":10511,"date":"2026-09-02T13:42:47","date_gmt":"2026-09-02T17:42:47","guid":{"rendered":"https:\/\/pirg.org\/maryland\/articles\/explainer-what-are-pfas\/"},"modified":"2026-09-09T13:01:23","modified_gmt":"2026-09-09T17:01:23","slug":"explainer-what-are-pfas","status":"publish","type":"article","link":"https:\/\/pirg.org\/maryland\/articles\/explainer-what-are-pfas\/","title":{"rendered":"Explainer: What are PFAS?"},"featured_media":67004,"template":"","meta":{"_acf_changed":false,"_yoast_wpseo_meta-robots-noindex":false,"_yoast_wpseo_meta-robots-nofollow":false,"_yoast_wpseo_opengraph-title":"","_yoast_wpseo_opengraph-description":"","_yoast_wpseo_twitter-title":"","_yoast_wpseo_twitter-description":""},"campaign_tax":[179],"display_option":[],"issue_tax":[],"person_tax":[],"region_tax":[],"state":[2],"topic_tax":[143],"class_list":["post-10511","article","type-article","status-publish","hentry"],"acf":{"details":{"helper_taxonomies":{"topics":[143],"collection":false,"press_type":false,"person_type":false,"resource_type":false,"event_type":false,"campaigns":179,"department":false,"level":false,"states":[2],"act_option":false,"display_option":false,"primary":{"topic":143}},"featured_image":67004,"caption_override":"PFAS have been detected in drinking water supplies in all 50 states. Even at low levels of exposure, PFAS have been linked with serious health impacts, including some types of cancer.","excerpt":"What are \u2018forever chemicals\u2019? How did they end up virtually everywhere in our environment? And what does it all mean for our health?","updated_on":null,"sidebar_action":[9920],"hide_hero_image":false,"sidebar_action_query_string":""},"helper_people_group":{"title":"Authors","entities":[{"type":"dynamic","dynamic_person":{"site":2,"people":"1025"},"information":{"name":"","image":null,"role":"","biography":"","contact":{"twitter":"","facebook":"","email":"","phone":""}}},{"type":"dynamic","dynamic_person":{"site":4,"people":"26001"},"information":{"name":"Stephanie Seferian","image":58673,"role":"Deputy Editor, Editorial & Creative Team, The Public Interest Network","biography":"","contact":{"twitter":"","facebook":"","email":"","phone":""}}},{"type":"manual","dynamic_person":{"site":4,"people":"23672"},"information":{"name":"Stephanie Seferian ","image":58673,"role":"Deputy Editor, Editorial & Creative Team, The Public Interest Network","biography":"","contact":{"twitter":"","facebook":"","email":"","phone":""}}}]},"page_layout":[{"acf_fc_layout":"layout_wysiwyg","_acfe_flexible_toggle":null,"component_wysiwyg":{"content":"Americans are becoming increasingly concerned about their exposures to a class of chemicals known as PFAS. Here\u2019s a brief explanation of what PFAS are, how they\u2019ve spread throughout the environment, and the implications for our health.\r\n

What are PFAS?<\/h3>\r\nIn 1938, Roy J. Plunkett was a young chemist working for DuPont.\r\n\r\nWhile working in the lab, Dr. Plunkett stumbled<\/a> into creating a new chemical compound\u2014a waxy substance that proved remarkably resistant to water. It turned out to be a game-changer.\r\n\r\nBy 1942, the new compound was being used in gaskets and valves that helped Manhattan Project scientists enrich uranium for the first atom bomb. Large-scale production of Plunkett\u2019s new chemical compound, which most of us know as Teflon, began soon after. But the non-stick and non-stain properties of this miracle substance also offered the allure of convenience. And so later on, Teflon and a spiraling number of variants began appearing in non-stick pans (less scrubbing!), stain repellant carpets (less cleaning!), and even cosmetics (improved texture and consistency<\/a>!).\r\n\r\nSo PFAS began bringing us more convenience. But at what cost?\r\n\r\nToday, nearly 15,000<\/a> chemical substances collectively known as PFAS\u2014the scientific acronym for per- or polyfluoroalkyl substances\u2014are in use throughout the American economy.\r\n

Why are PFAS called \u2018forever chemicals\u2019?<\/strong><\/h3>\r\nThe superpower behind PFAS chemicals lies in their exceptionally strong bond<\/a> of carbon and fluorine atoms, which, in turn, makes these chemicals exceptionally durable.\r\n\r\nThe super-strong carbon-fluorine bond is also what makes PFAS so effective in keeping the buttery grease from bleeding through your popcorn bag, the rain and snow from permeating your jacket, and your dental floss from getting stuck between your molars and bicuspids.\r\n\r\nThis powerful chemical bond also means that PFAS tend to remain as the toxic compounds they are once released into in the natural world. Unlike food waste, yard waste or paper goods, PFAS do not readily decompose when exposed to sunlight or water. Some PFAS can stay in our bodies for years.\r\n\r\nThat\u2019s why the PFAS put into the environment five years, 10 years, or 20 years ago are still around. That\u2019s also how they earned their nickname \u201cforever chemicals.\u201d\r\n

How have PFAS spread in the environment?<\/h3>\r\nBecause PFAS are so effective, they\u2019re used in an astonishingly wide range of products and machines.\r\n\r\nThe auto industry<\/a> has used PFAS in car engines as well as in the textiles, upholsteries, carpets and leather in the interior of our vehicles. Companies that make personal care products have used PFAS in dental floss, shampoos and cosmetics. Sporting goods companies have used PFAS in outdoor gear and ski wax<\/a>.\r\n\r\nSo, if you add it all up, how many products contain PFAS? It\u2019s impossible to say. Thousands, at least. Which helps explain in part why PFAS can be found almost everywhere in the natural environment.\r\n

How does PFAS get from the environment into our bodies?<\/h3>\r\nThere are three main pathways:\r\n
    \r\n \t
  1. Direct exposure<\/strong> via personal care products and cosmetics<\/li>\r\n \t
  2. Through our food<\/strong> from food packaging, pesticides, and PFAS-laden sewage sludge spread on farmland<\/li>\r\n \t
  3. Through drinking water contamination<\/strong> from factories dumping directly into rivers and groundwater; burning and burying PFAS-laden products that have been thrown away; the direct use of PFAS products like certain firefighting foam (Aqueous Film-Forming Foam, AFFF) as it seeps into ground and well water; and industrial and residential waste sent to sewage plants, which is then either released to rivers or winds up in sewage sludge that is spread on farmland<\/li>\r\n<\/ol>\r\nIt\u2019s estimated that PFAS is in nearly half<\/a> of America\u2019s tap water, according to a U.S. Geological Survey study. They can be found in the blood of an estimated 98%<\/a> of Americans, according to another study. They\u2019ve even been found in fertilizer<\/a> made from sewage sludge used to grow crops.\r\n\r\nTo sum up:<\/strong> For decades PFAS have been used in thousands of consumer and industrial products. And because these compounds never fully break down, they\u2019ve kept accumulating, year after year after year, in our water, soil, air, food and bodies.\r\n

    How could exposure to PFAS affect people\u2019s health?<\/h3>\r\nFor decades, evidence has been piling up linking PFAS to a wide range of damaging effects to the health of people (not to mention the health of other species<\/a>). While industry documents<\/a> suggest that PFAS producers knew that these chemical compounds were dangerous as early as 1970, the risks didn\u2019t become widely known until the 1990s. So far, studies have found links between PFAS exposures and health disorders including:\r\n