forever chemical
noun
plural forever chemicals
: a toxic substance and especially a synthetic chemical (as of the per- and polyfluoroalkyl substances group) that persists and accumulates in the environment
—not used technically
Canadian researchers have discovered high levels of a "forever chemical", used in making toilet paper, in the bodies of endangered killer whales, sparking fears the toxic substance could further harm them.—Leyland Ceccoin
Landfills, military bases and firefighting training centers also are thought to be sources of forever chemical pollution.—Sammy Fretwell
—often used in pluralPFAS, or per- and polyfluoroalkyl substances, are colloquially known as "forever chemicals" because they are so difficult to break down.—Layne Cameron
Forever chemicals are used as surface treatments to block water and stains. In fact, a 2022 report by Toxic-Free Future, an environmental health research and advocacy organization, found that nearly three-quarters of products labeled as water- or stain-resistant tested positive for them.—Hannah Norman
PFAS, a group of manufactured chemicals commonly used since the 1940s, are called "forever chemicals" for a reason. Bacteria can't eat them; fire can't incinerate them; and water can't dilute them.—Amanda Morris
Van Zile said many people love a Wisconsin Friday fish fry, but many fish are found with high levels of forever chemicals, such as mercury, and that we're slowly poisoning ourselves.—Frank Vaisvilas
Cite this Entry
“Forever chemical.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/forever%20chemical. Accessed 5 Aug. 2026.
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