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People who had elevated blood levels of a toxic chemical called perfluorobutanoic acid (PFBA) had an increased risk of a more severe course of COVID-19 than those who did not have elevated levels, according to a new study led by Harvard T.H. Chan School of Public Health. PFBA is part of a class of man-made chemicals known as perfluorinated alkylate substances (PFASs), which have previously been shown to suppress immune function.
The study, published Dec. 31, 2020 in PLOS ONE, was led by Philippe Grandjean, adjunct professor of environmental health.
PFASs have water- and grease-resistant properties and are used in a wide variety of products, including nonstick cookware, waterproof clothing, food packaging, and firefighting foams. PFBA, more than other PFASs, is known to accumulate in the lungs, according to the study.
Researchers looked at PFAS levels in blood samples from 323 Danish individuals infected with the coronavirus. They found that those with higher PFBA levels had higher odds of being hospitalized, winding up in intensive care, and dying than those with lower levels.
The findings suggest that further study is needed to determine whether elevated exposures to other environmental immunotoxicants may worsen COVID-19 outcomes, the authors wrote.
