Some consumer behaviors including the use of Oral-B Glide dental floss contribute to elevated levels of toxic perfluoroalkyls (PFAS) in the body, according to the Silent Spring Institute and the Public Health Institute (PHI) in Berkeley, California.
PFAS are waterproof and grease-proof substances that have been linked with numerous health problems, the researchers report. They are used in a range of consumer products including fast food packaging, non-stick pans, waterproof clothing, and stain-resistant carpets.
People can be exposed to PFAS directly through the products they use and food they eat. They also can be exposed through indoor air and dust and contaminated drinking water. Health impacts include kidney and testicular cancer, thyroid disease, high cholesterol, low birth weight, decreased fertility, and effects on the immune system.
The researchers measured 11 PFAS chemicals in blood samples taken from 178 middle-aged women enrolled in PHI’s Child Health and Development Studies, a multigenerational study of the impact of environmental chemicals and other factors on disease.
Then, the researchers compared the blood measurements with results from interviews in which they asked the women about nine behaviors that could lead to higher exposures. Half of the women in the analysis were non-Hispanic white, and half were African American.
Women who flossed with Oral-B Glide tended to have higher levels of a type of PFAS called PFHxS in their body compared to those who didn’t.
To further understand the connection, the researchers tested 18 flosses including three Glide products for the presence of fluorine, a PFAS marker, using particle-induced gamma-ray emission spectroscopy.
All three Glide products tested positive for fluorine, consistent with reports that Glide is manufactured using Teflon-like compounds. Also, two store brand flosses with “compare to Oral-B Glide” labelling and one floss marketed as a “single strand Teflon fiber” tested positive for fluorine.
“This is the first study to show that using dental floss containing PFAS is associated with a higher body burden of these toxic chemicals,” said lead author Katie Boronow, MS, staff scientist at Silent Spring. “The good news is, based on our findings, consumers can choose flosses that don’t contain PFAS.”
Other behaviors associated with higher PFAS levels included having stain-resistant carpet or furniture and living in a city served by a PFAS-contaminated drinking water supply.
Also, African American women who frequently ate prepared food in coated cardboard containers such as French fries or takeout had elevated blood levels of four PFAS chemicals compared to women who rarely ate such food. The researchers did not see the same relationship with prepared food among non-Hispanic whites.
Non-Hispanic whites tended to have higher levels of PFOA and PFHxS than African Americans. The researchers could not explain the differences, suggesting that there are other behaviors they didn’t measure that contribute to PFAS exposure.
“Overall, this study strengthens the evidence that consumer products are an important source of PFAS exposure,” said Boronow. “Restricting these chemicals from products should be a priority to reduce levels in people’s bodies.”
The study, “Serum Concentrations of PFASs and Exposure-Related Behaviors in African American and Non-Hispanic White Women,” was published by the Journal of Exposure Science & Environmental Epidemiology.