Exposure to Chemical Flame Retardants Can Cause Neurological Impairments
Chemical fire retardants, added to commercial materials since the 1970s, are leeching into our environment and into our bodies.
-- by Joann Jovinelly
Attention deficit/hyperactivity disorder (ADHD) may not be the reason Johnny can’t pay attention.
In a new study published this month in the journal Environmental Health Perspectives, researchers linked high prenatal and childhood exposures to household chemicals, namely polybrominated diphenyl ethers, or PBDEs, a class of chemical compounds commonly used as fire retardants since the 1970s.
Many items commonly found in the home contain PBDEs, like carpet padding, foam mattresses and furnishings, upholstery, construction and insulation materials, computers, cell phones, and other electronics. (The chemicals can also be found in fatty foods like meat, larger fish, and even in dairy products like milk and butter, as was reported in this 2011 study, also published in Environmental Health Perspectives.)
The problem with PBDEs is that they are not chemically bound to the materials to which they were added, so they break down over time as pollution. The chemicals disperse into the air as a gas or physically break down into dust; they are then ingested and stored in human and animal fat cells.
In the most recent study of the affect of PBDE exposure, researchers at the University of California, Berkeley have linked the chemicals to a growing list of neurological and cognitive health problems in school-age children. Those results show that children exposed to higher-than-normal levels of PBDE compounds have poor attention spans, impaired fine motor coordination, and low IQ.
The Expert Take
“This is the largest and most comprehensive study to date to examine neurobehavioral development in relation to body burden measures of PBDE flame retardants,” said lead study author Brenda Eskenazi, Ph.D., a professor in the School of Public Health at the University of California, Berkeley.
“We measured PBDEs both in the mothers during pregnancy and in the children themselves," continued Eskenazi. "[The study] shows that there is a relationship of in utero and childhood levels to decrements in fine motor function, attention, and IQ."
Source and Method
Participants in the latest study also participated in a related longitudinal study, the Center of the Health Assessment of Mothers and Children of Salinas (CHAMACOS), which examined relationships between environmental chemical exposures and reproductive health. The CHAMACOS group had PBDE blood levels that were seven times higher than normal.
Researchers took blood samples from 279 pregnant CHAMACOS women, as well as from 272 of the children born to those women when they reached the age of seven, and sent them to the Centers for Disease Control and Prevention (CDC) for testing.
To measure neurological and cognitive deficits, the same children were put through a battery of tests at age five and again at age seven that measured fine motor coordination, memory, attention, and IQ (reading comprehension, processing speed, verbal skills).
Nearly all U.S. residents have measurable levels of PBDE exposure in their blood, with those in California at risk for excessively high amounts (likely because of laws in that state that heavily enforced the use of flame retardant materials due to wild fires). About five percent of the U.S. population has PBDE exposure rates that are considered “high” according to Heather Stapleton, professor of environmental chemistry at Duke University and an expert on human exposure to flame retardant materials.
And PBDEs are still in moderate use today, though they are either completely banned or currently being phased out in California, Washington State, and Maine. Mostly, the chemical compounds are present in products made before 2004.
To reduce the risk of PBDE contamination in the home, repair and seal any open tears in upholstered furniture or mattresses. Clean surfaces and floors at least twice weekly with a damp cloth, mop, and/or vacuum. Frequent hand washing is also advisable, especially for children.
Growing evidence suggests that because of the long-term use of PBDEs, and the fact that they are easily stored in the fatty tissue of the human body, many more people have been adversely affected by higher-than-normal exposure.
For instance, according to the CDC, “several studies of U.S. residents have shown increasing levels of BDE-47 during recent decades that were three to 10 times higher than contemporary European residents.”
One problem may be that Americans are getting exposed from a number of places, including from products in the home, from the food they eat, from environmental waste, and, in the case of children, from human breast milk.
According to a report released in 2010 by the U.S. Environmental Protection Agency (EPA), “toddlers have been shown to have a greater concentration of PBDEs in their bodies, most likely due to breast milk consumption and increased exposure to the chemicals in household dust.”
Unfortunately, the adverse health affects of PBDE exposure is not limited to the neurological and cognitive deficits discussed in this article. In a 2004 study published by Environmental Contamination and Toxicology, “repeated exposure to PBDEs results in thyroid hormone disruption, developmental neurotoxicity, changes in fetal development, and [chemical-driven liver damage].”
Exposure to PBDEs has also been linked to the interference or blocking of hormones, delayed puberty, and infertility.