Next time you're ordering from a favorite fast food place, or tossing some popcorn in the microwave, think about this... the chemicals that are used to make food wrappers like grease-proof paper have also been found, for the first time ever, someplace you might not like - in human blood.
This according to startling new research in the journal Environmental Science & Technology, the latest in a series of studies that date back to the late 1990s on compounds known as perfluorochemicals or PFCs for short.
And since we're abbreviating, there's PFOA (perfuorooctanoic acid) a rather worrisome member of this family; PFOS (perfluorooctane sulfonate) is another. Finally diPAP (polfluoroalkyl phosphoric acid diesters) is the compound that keeps the wrapper around your food from getting greasy.
Scott Mabury, a chemist at the University of Toronto and his team, wanted to learn more about the as-yet-unstudied precursor to PFOA, diPAP, a chemical used to make fast food wrappers resist grease.
He suspected these substances were leaking from the wrappers into the food, and it turns out he was right.
These chemicals aren't sold commercially, rather they're products or aids to processing used to make other things.
Both PFOA and PFOS resist oil and water, so they're ideal as linings for carpets as well as the coating on non-stick pans, but you'll also find them in our clothes and electronics, and in food packaging like microwave popcorn bags and pizza boxes. They are used by the biggest brands like Teflon, Stainmaster, Scotchgard and Gore-Tex.
The team used a very sensitive, half million dollar mass spectrometer to look at 20 pooled blood samples, collected all across the Midwestern U.S. of both men and women ranging in age from 19 to 70 years old.
Each pooled sample was made up of ten different blood donors. The first ten collected during 2004-2005, another ten in 2008.
Surprisingly, the team saw levels of diPAPs in the samples, even though they'd expected this compound to break down quickly and be undetected - yet it was at the same high levels as PFOA.
The researchers also analyzed extracts from six sewage sludge samples that had been collected in waste treatment plants in Canada during 2007.
These samples also contained high levels of diPAPs, which suggests the compound is already in drinking water and farms.
Animals, even those in locations as remote at the Artic, too have levels of these compounds in their blood.
The team suspects that diPAPs might be contributing to as much as 10% of the PFOA in our own bloodstream. What's more, the other steps in the breakdown process can bring forth molecules that have been shown in studies to be ten thousand times more toxic than PFOA.
"The take-home message is that some chemicals that make our lives easier, better and more satisfying end up in our bloodstream with unknown toxicological consequences," warns study co-author Mabury.
He also points out that, "The diPAPs occur at levels in human blood that are comparable to PFOA. We know diPAPs don't last long in the body, so this suggests an important and fairly constant source."
When little-understood compounds like these end up in our food and our environment they're able to enter our bodies, our drinking water and the bodies of other animals, even those very far removed from our civilized world, like Polar bears in the Artic harbor.
So far, perfluorochemicals have been found in every human blood sample tested, and at pretty high levels too. In animal studies PFOA and PFOS have been tied to developmental problems, cancer and other.
The U.S. Environmental Protection Agency has convinced American manufacturers to stop using PFOS, and has encouraged other firms to find alternatives and cut emissions of PFOA, as well as many of the super dangerous precursor molecules.
The U.S. Food and Drug Administration studies show that diPAPs and other such chemicals can migrate in to some foods at levels that are several hundred times higher than the currently approved guidelines.
No one, so far, has studied the health effects in people of exposure to the grease reducing chemicals, or the by products of these substances.
Until more is know, your best bet is to limit your exposure as much as possible to plastic packaging wherever possible to avoid chemicals in body building up.
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