From Environment News Service:
Chemicals used to keep grease from leaking through fast food wrappers and microwave popcorn bags are migrating into food, being ingested by people and showing up as contaminants in blood, according to new research at the University of Toronto.
The contaminants are perfluoroalkyls, stable, synthetic chemicals that repel oil, grease, and water. They are used in surface protection products such as carpet and clothing treatments and coating for paper and cardboard packaging.
Earlier research by University of Toronto environmental chemists Scott Mabury and Jessica D’eon, established in 2007 that the wrappers are a source of these chemicals in human blood. Their new study shows that perfluorinated chemicals can migrate from wrappers into food.
The specific chemicals studied are polyfluoroalkyl phosphate esters, or PAPs, breakdown products of the perfluorinated carboxylic acids, or PFCAs, which are used in coating the food wrappers.
“We suspected that a major source of human PFCA exposure may be the consumption and metabolism of polyfluoroalkyl phosphate esters, or PAPs,” said D’eon, a graduate student in the University of Toronto’s Department of Chemistry.
“PAPs are applied as greaseproofing agents to paper food contact packaging such as fast food wrappers and microwave popcorn bags,” she explained.
In their latest study, D’eon and Mabury exposed rats to PAPs either orally or by injection and monitored for a three-week period to track the concentrations of the PAPs and PFCA metabolites in their blood.
The researchers used the PAP concentrations previously observed in human blood together with the PAP and PFCA concentrations observed in the rats to calculate human exposure to the chemical perflurooctanoic acid, PFOA.
“In this study we clearly demonstrate that the current use of PAPs in food contact applications does result in human exposure to PFCAs, including PFOA,” said Mabury, the lead researcher and a professor in the university’s Department of Chemistry.
Elevated levels of PFOA in blood have been associated with changes in sex hormones and cholesterol, according to the U.S. Agency for Toxic Substances. Exposure to PFOA also has resulted in early death and delayed development in mice and rat pups, the agency says.
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