A new study led by a team of Boston University School of Public Health researchers has found that a group of chemicals widely used in many consumer products is linked to the condition called “Attention Deficit Hyperactivity Disorder” (ADHD) in children.

Commonly referred to as PFCs (which stands for “polyfluoroalkyl chemicals”, but you may also have heard of them as perfluorinated compounds), they are used in so many industrial and commercial products that almost everyone in the U.S. and around the world is constantly exposed to them.

PFCs are used in clothing, furniture and carpets to provide stain-resistance; in water-resistant coatings, grease-resistant food packaging like popcorn bags and pizza boxes; Teflon, cleaning products, personal care products like shampoo, and so on. They’re everywhere. When they are absorbed into the body it can take years to even partially eliminate them.

The new study linking PFCs to “ADHD”, which was published in the journal Environmental Health Perspectives, used data from the National Health and Nutrition Examination Survey (NHANES) to compare the PFC levels found in serum samples from 571 children aged 12 to 15, including 48 kids with diagnosed “ADHD”. The study found “increased odds of ADHD in children with higher serum PFC levels.”

An earlier NHANES survey, performed in 2003-2004, analyzed 2,094 blood samples taken from the U.S. population and found more than 98 percent had detectable serum levels of PFCs.

PFCs aren’t anything new. As far back as the 1980s, the DuPont company, which manufacturers a number of PFCs, showed how PFCs can cross the placental barrier of women exposed to the chemical and cause developmental abnormalities in their children.

Workers at a DuPont factory in West Virginia had “statistically significantly higher” incidences of cancers, including cancer of the buccal cavity (the cavity between the jaw and the cheeks), the pharynx, kidney, other urinary cancers, and leukemia. Male workers at a Minnesota 3M plant had double the normal death rate from prostate cancer and female workers had abnormally high levels of the reproductive hormone estradiol, which is linked to breast and ovarian cancer.

Other studies performed in the 1990s at factories where PFCs were manufactured showed double and higher occurrences of disease than elsewhere.

Animal studies have also shown that PFCs may be potential “developmental neurotoxicants” — causing toxic damage to nerves involved in mental and physical development.

According to a 2004 report from the Environmental Protection Agency (EPA), the industry knew about the dangers, did nothing to protect its workers and hid from the EPA the known human health effects.

Although the Boston University School of Public Health researchers can’t say for sure that PFCs cause the symptoms known as ADHD, there is certainly enough evidence of health effects to warrant avoiding them.

SOURCES: Environmental Working Group report on PFCs, June 2008, Environmental Health Perspectives, June 2010, http://ehp03.niehs.nih.gov/article/info%3Adoi%2F10.1289%2Fehp.1001898; Boston University School of Public Health, August, 2010, http://sph.bu.edu/insider/index.php/Recent-News/busph-researchers-link-widely-used-chemicals-to-adhd-in-children.html