Food packaging from around the world contains at least 68 "forever chemicals" that can seep into what we eat. a new study finds. And 61 of them are not even supposed to be used in such products. "It's not clear why the latter chemicals, which are not on lists of those authorized for use in food containers, are in such packaging." says the study's author Birgit Geueke.
The study focused on a class of chemicals called perfluoroalkyl and polyfluoronlkyl substances (PFASs), which are sometimes called "forever chemicals" because they don't break down readily in the environment or in the body. That's because their characteristic carbon-fluorine bond is one of the strongest in nature. For decades, these substances have been used in a wide range of consumer products, from cookware to pesticide s to cosmetics, because they are proof against water and grease.
Geueke and her team found a mismatch between what they detected in actual products and a database of PFAS chemicals authorized for use in food packaging. About 140 PFASs are known to be used in food packaging, but only seven of the 68 chemicals in the study were on this list. Geueke says it's unclear how or why the other 61 chemicals turned up. David Andrews, a chemist and toxicologist at a nonprofit environmental advocacy organization, suggests it's possible that unknown impurities emerged during the manufacturing of the authorized chemicals or that the authorized PFASs degrade over time. This class of chemicals includes many long-chain molecules, and they can break into shorter chains that are simply different types of PFASs.
PFASs have been found in human blood and breast milk, drinking water, soil and other startling places around the world. Exposure to some of the most studied PFASs has been associated with cancer. reproductive problems and lessened responses to vaccines. "There's an incredible body of scientific evidence linking PFAS chemicals to health harm," says Andrews. Many countries are evaluating restrictions of PFASs in food packaging.
Chemical industry representatives have advocated for dealing with PFASs as individual chemicals. Before publishing the new study. Scientific American reached out to the American Chemistry Council (ACC). a chemistry industry trade association, about it, but the organization did not reply. On its dedicated PFAS webpage. ACC notes that "all PFASs are not the same. Each individual chemical has its own unique properties and uses."
Andrews and Geueke both say the presence of unknown PFASs in food packaging is good reason to regulate these chemicals as a single class—a position shared with many other scientific experts and environmental protection groups. There are more than 12,000 known PFASs, and scientists don't know much about most of them. "Only some PFASs have ever been tested for toxicity (每性)," Geueke says, and "there are probably other ways to produce food packaging."
