Non-stick chemicals and cholesterol

The following is a partial transcript; for full story, listen to audio.

Two new studies are raising concerns about some chemicals and cholesterol. Polyfluoroalkyl chemicals, or PFCs, have a long history in common consumer products like Teflon, stain-resistant fabrics and even some food wrappers. PFCs made those products non-stick, but the chemicals do stick around in our bodies, and it could be raising cholesterol.

Health researcher Jessica Nelson conducted one of those studies at Boston University’s School of Public Health.

“Our study found that higher levels in blood of three of these PFC chemicals was associated with higher levels of bad cholesterol. And this was in a sample of the general U.S. populations.”

According to Nelson, more research is needed to determine the specific ways in which people are exposed to the chemicals, but she has a few theories.

“The likely pathways are through ingestion of food and drinking water. But, possibly also ingestion and inhalation of dust and air in homes. And basically products where chemicals are used to make them more stain, oil, water, grease-resistant. So, possible products are things like pizza boxes, takeout food wrappers, carpet treatments, textile treatments — it’s a pretty broad category of products that a lot of us encounter everyday.”

Unlike other chemicals that build up in fat deposits, these chemicals bind to proteins says Nelson, “… so they might be binding to proteins in our blood, proteins in our liver, proteins in other tissues, and that’s why they’re sort of in our bodies for a number of years.”

Some of the major users of PFCs — DuPont, 3M, other companies — have entered into a voluntary agreement with the U.S. Environmental Protection Agency to phase out the use of some of these chemicals. But this doesn’t mean they’ll be going away any time soon.

“First of all, as we’ve talked about, they’re persistent, so they stick around in our bodies for years,” said Nelson. “And, they also are persistent in the environment, so just because we stop them today doesn’t mean that they’re going to go away in the environment. There’s also a possibility that some other PFC chemicals that haven’t been phased out may actually break down into PFAS and PFOA– those are the two chemical and chemistries that are being phased out.

But not all of them have been eliminated, so one of the chemicals in our study that we did find this association with, PFNA, has not been phased out. And, in fact, we know that blood concentrations in people seem to be increasing for this chemical rather than decreasing.”

Nelson cautions that her study does not show a definitive a cause-and-effect relationship between PFCs and cholesterol.

“One caveat that I want to give is that this is an exploratory study and there definitely are limitations to what we can say about it. It was an association study, so we really don’t feel we can say it’s a cause and effect relationship at this point. We know enough to know that we should be concerned and that we should aggressively pursue future research. But, unfortunately, it’s too early to sort of make that causal connection about your cholesterol levels or my cholesterol levels at this point.”

Hosted by Steve Curwood, “Living on Earth” is an award-winning environmental news program that delves into the leading issues affecting the world we inhabit. More “Living on Earth.”