Another new study has linked human exposure to C8 and similar chemicals to food wrappers.
The study, published in summary form online in the journal Environmental Health Perspectives, found that 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 in human blood.
University of Toronto experts Scott Mabury and Jessica D’eon, who have performed previous studies of the food wrapper-C8 connection, did this latest study.
This particular study looked at polyfluoroalkyl phosphate esters, or PAPs, breakdown products of the perfluorinated carboxylic acids, or PFCAs, which are used in coating the food wrappers. Rats were exposed to PAPs and monitored for three weeks to track the concentrations of PAPs and PFCA in their blood. The researchers then used the PAP concentrations previously observed in human blood together with PAP and PFCA concentrations in the rats to calculate human exposure to perflurooctanoic acid, better known as PFOA or C8.
We suspected that a major source of human PFCA exposure may be the consumption and metabolism of polyfluoroalkyl phosphate esters or PAPs. PAPs are applied as greaseproofing agents to paper food contact packaging such as fast food wrappers and microwave popcorn bags.
We found the concentrations of PFOA from PAP metabolism to be significant and concluded that the metabolism of PAPs could be a major source of human exposure to PFOA, as well as other PFCAs.
This discovery is important because we would like to control human chemical exposure, but this is only possible if we understand the source of this exposure. In addition, some try to locate the blame for human exposure on environmental contamination that resulted from past chemical use rather than the chemicals that are currently in production.
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. We cannot tell whether PAPs are the sole source of human PFOA exposure or even the most important, but we can say unequivocally that PAPs are a source and the evidence from this study suggests this could be significant.