Given that the chemicals are found in many common household goods -- including pizza boxes, carpets, and non-stick pans -- more children than expected may be at risk.
The study, which was published last week in the Journal of the American Medical Association, found that children with high amounts of PFCs in their bloodstreams produced fewer antibodies after receiving vaccines for Diphtheria and Tetanus -- so few that they could be at risk for getting those diseases, in spite of the vaccinations.
"When the PFC concentration increases in the body, the immune system gets more sluggish and is less capable of maintaining a defense mechanism against microorganisms," the study's lead researcher, Dr. Philippe Grandjean of the Harvard School of Public Health in Boston, told Reuters.
PFCs cause reproductive and developmental problems in laboratory animals, the EPA says, but have not officially been found to be toxic to humans. Small amounts of PFCs can be found in everything from food containers and microwave popcorn bags to paints, pesticides, and flame-retardant clothing; Stainmaster, Teflon, and Scotchguard are some well-known brands containing PFCs. But much larger amounts of PFCs are produced when non-stick and stain-repellent products are manufactured and they often end up contaminating the ground and water supplies.
PFCs don't biodegrade, and have been building up in the environment since at least the 1950s. Fish caught in contaminated waters have high levels of pollutants including PFCs; according to the EPA, consumption of contaminated food and drinking water are probably the main ways we're exposed to the chemicals.
"I don't feel comfortable with the compounds for myself and my family and would rather eliminate them," Grandjean told Reuters.
Grandjean and his team took blood samples from 587 pregnant women in the Faroe Islands, near Iceland and Scotland, and tested them for five common PFCs. They repeated the test using blood samples from the children when the kids were 5 years old, after they'd received their diphtheria and tetanus vaccinations, and again after a booster shot at age 7.
"A doubling of PFOS in the mother's blood resulted in a 39 percent decrease in diphtheria antibody in the child at age five. A doubled PFOA concentration in the child's blood at age 5 meant a decrease in antibodies at age seven of 36 percent and 25 percent to tetanus and diphtheria respectively," The Atlantic reported.
(Why women from a remote island in Northern Europe? Because they eat a fish-based diet, and fish and seafood are more likely to have high levels of PFCs.)
If kids aren't responding to vaccines the way they're supposed to, then the study's findings may point to an even bigger issue, Grandjean says: The possibility of an infectious disease epidemic. Antibodies created in response to a vaccine can indicate how well a person's immune system response in general, so if PFCs have an effect on the way kids' react to Diphtheria and Tetanus, it could also mean that they're having problems creating antibodies for other diseases.
Marie Francis, a spokesperson for the American Chemistry Council, a trade association representing chemical manufacturers, said in a statement that the chemical industry is "carefully reviewing" the new study.
"It is important for consumers to know that our companies, working with the EPA, have made marked progress towards advancing new chemistries that are substitutes for the older chemicals evaluated in this study," Francis said. "These new fluoro chemistries have an improved environmental and toxicological profile while continuing to offer consumer benefits."
It's difficult to avoid PFCs entirely, because they're in so many things, including the containers many processed foods come in and the building materials our houses are made out of. The U.S. government doesn't require that companies say whether a product contains the chemicals, Grandjean points out, and China, which supplies many of the goods sold in the U.S., doesn't restrict PFC use at all.
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