When it comes to tooth decay, poor nutrition and hygiene typically get most of the blame. But there are other risk factors, too, such as chronic dry mouth, bruxing (habitual grinding) – and, according to new research in the Journal of Public Health Dentistry, possibly a common chemical: perfluorodecanoic acid (PFDA).
PFDA is one of a number of synthetic chemicals called per- and polyfluoroalkyl substances, or PFAS for short, which are used widely in manufacturing. These chemicals hang around a long time, in both our environment and in the human body – and have been found to have some alarming effects on our health.
Studies indicate that PFOA and PFOS can cause reproductive and developmental, liver and kidney, and immunological effects in laboratory animals. Both chemicals have caused tumors in animal studies. The most consistent findings from human epidemiology studies are increased cholesterol levels among exposed populations, with more limited findings related to: infant birth weights, effects on the immune system, cancer (for PFOA), and thyroid hormone disruption (for PFOS).
Because they’re so persistent, even those that have been banned still linger in our water, air, and soil – and in us. They can be particularly prevalent in drinking water systems.
The new study focused on NHANES data from 629 children between the ages of 3 and 11, including samples of blood analyzed for PFAS between 2013 and 2014. Tooth decay and factors such as race, BMI, and hygiene practices were also assessed.
While 7 PFAS were identified, it was PFDA that was linked to higher rates of tooth decay.
Why should this be? The study didn’t look for a mechanism, but the researchers offered one possible explanation:
According to other research, perfluorodecanoic acid may disrupt the health of enamel, which is what makes teeth hard. That disruption can leave teeth susceptible to decay.
But there is some good news. For one, about half the kids in the study showed no detectable levels of PFAS. And those who brushed twice a day and had regular dental visits had less decay than those whose oral care wasn’t so great.
Of course, the other thing you can do is take steps to limit your family’s exposure to PFAS. Do be aware, though, that while home water filters can remove some of these contaminants, not all filters are equal. In fact, a study published earlier this year out of Duke University found that most were only partially effective, while “a few, if not properly maintained, can even make the situation worse.”
“All of the under-sink reverse osmosis and two-stage filters achieved near-complete removal of the PFAS chemicals we were testing for,” Stapleton said. “In contrast, the effectiveness of activated-carbon filters used in many pitcher, countertop, refrigerator and faucet-mounted styles was inconsistent and unpredictable. The whole-house systems were also widely variable and in some cases actually increased PFAS levels in the water.”
The average amount of removal by carbon filters was 73%, and the numbers swung pretty wildly among the filters tested. Those under-sink reverse osmosis units and two-stage filters, on the other hand? They removed 94% of PFAS.