Key News in Family Medicine January 18, 2019 (9 of 12)

Eating and flossing are routine tasks for many people. However, a new study has shown that they could expose people to potentially dangerous chemicals.

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are now part of everyday life. These water and grease-proof substances are present in many products, from fast food containers to certain types of clothing. Humans are also exposed through contaminated water and even dust. However, what is most worrying – according to the Environmental Protection Agency (EPA) – is that these man-made chemicals continue to accumulate in the body without degrading. Regular exposure to the PFAS has led some researchers to examine their impact on human health. Until now, the results have shown a link with health problems such as hypercholesterolemia, kidney and testicular cancer and thyroid disease.

A new study has looked further into typical human behaviors to determine if any of them were badociated with exposure to PFAS. The participants were 178 middle-aged women, half of whom were African American and the other half non-Hispanic Caucasian. These women were already part of the Child Health and Development Studies of the Institute of Public Health, which included pregnant women living in Oakland, California, in 1959-1967. Its purpose was to determine the impact of environmental chemicals and other factors on diseases.

PFAS levels of flossing

Scientists from the Silent Spring Institute and the Public Health Institute in Berkeley, California, used blood samples taken from women in 2010-2013. They examined the samples to find the levels of 11 types of PFAS. They also interviewed each woman at one point in 2015-2016, asking a series of questions about potential behaviors related to exposure to the PFAS. They discussed food consumption, flossing and stain resistant furniture and carpets.

Once the scientists determined all the blood measurements, they compared them to the answers provided by the women. They took into account factors such as whether people lived in areas where water was contaminated by the PFAS. The results appear in the Journal of Exposure Science & Environmental Epidemiology.

The most striking observation of the study is that some dental wires appear to cause high levels of PFAS. Researchers further investigated this combination by testing 18 different wires for the presence of fluorine, which also indicates the presence of PFAS. They revealed that Glide and three non-Glide threads were fluorine-positive. This is consistent with findings that showed that women who used a certain brand of Glide silk had higher PFAS levels in their blood called PFHxS.

Change behaviors

Other findings include that African-American women who reported eating regularly prepared foods in coated cardboard packaging, such as take-home food, had higher rates of four types of PFAS in the blood. This was compared to women who reported eating this kind of food rarely.

Living in a water-fed area with PFAS and in a house with stain-resistant carpets or furniture also showed links to higher blood levels of PFAS.

Scientists also noted that non-Hispanic white women had high rates of two PFAS: PFOA and PFHxS. It is not known why this was not the case for African-American women, but this difference could be the result of a type of behavior different from that which researchers did not measure.

The number of participants and the fact that the majority lived in California are also limits, as is the lack of research on Hispanics and Americans of Asian descent. Despite this:

"[T]This study is the first to show that the use of dental floss containing PFAS is badociated with a higher body burden in these toxic chemicals. The good news is that based on our findings, consumers can choose wires that do not contain PFAS. "

Katie Boronow, lead author

She explains that the results go in the direction of proving that consumer products increase exposure to PFAS and that companies should consider "limiting these chemicals" as a priority.