One thing fingernails, toenails and hair all have in common is that they're composed of the protein keratin. Yet did you know that chemicals found in flame retardants that are potentially toxic to humans can also hide in all three?
Researchers at Indiana University said they believe that a more easily available biomarker will help in determining how potentially dangerous chemicals commonly found in the environment influence human health, including chemicals in the air, indoor dust and even water.
"Little is known about the human exposure to flame retardants, especially new classes of the retardants," researcher Amina Salamova at the School of Public and Environmental Affairs at IU Bloomington, said. "The first step is to establish a relatively easy and reliable way of measuring chemical levels in people, especially children, and we've determined that hair and nails can provide exactly that."
Up until now, researchers actually looked at samples of blood, human milk and urine to try and determine exposure to flame retardants, which have been linked to obesity, reproductive toxicity, learning disabilities and endocrine disruption. Flame retardants are frequently added to plastic, foam, wood and textiles and are used in both commercial and consumer products worldwide to delay the ignition of fire. However, there's still relatively little know regarding their long-term affect on health, and previous research has shown that flame retardants persist in the environment and bioaccumulate in ecosystems and in human tissues.
During this recent study, researchers collected samples of hair, fingernails and toenails from about 50 students in Bloomington and then compared the levels of chemicals found in the samples to those found in blood from the same people.
Findings showed a strong relationship between the group of flame retardants known as polybrominated diphenyl ethers or (PBDEs) in hair and nails. Furthermore, women showed higher concentration levels of common flame retardants when compared to men in the study, which researchers said they believe may be caused by chemicals in nail polish.
The study, "Hair and Nails as Noninvasive Biomarkers of Human Exposure to Brominated and Organophosphate Flame Retardants," is published today in the journal Environmental Science and Technology.
