Flame retardant chemicals are all around us. They are found in computers, upholstered chairs, and mattresses. They were added with good intentions, for safety in case of fire. But many flame retardants are now thought to be toxic. One class of flame retardants, polybrominated diphenyl ethers (PBDEs), which is now banned, has been found to be toxic to the brain, liver, and other organs.
A new finding from the lab of CEEH member Dr. Lucio Costa in the Department of Environmental and Occupational Health Sciences (DEOHS), University of Washington School of Public Health, has found how one of these PBDEs, tetrabrominated diphenyl ether (BDE-47), exerts its toxic effects. Researchers from UW and the Department of Neuroscience at the University of Parma, Italy, found that particular types of receptors in the brain are involved in toxicity from BDE-47.
The results in mouse neurons suggest that BDE-47 increases the amount of the neurotransmitter glutamate. More glutamate in turn activates glutamate receptors and leads to increased calcium levels and oxidative stress. This causes brain cells to become over-activated, culminating in cell death. This sequence of events is especially harmful to the developing brains of infants and toddlers. It can lead to higher impulsivity and diminished attention and motor coordination.
The level of BDE-47 in people in the United States is about ten times higher than in Europe or Japan, because, in trying to prevent deaths from fires, the US required that flame retardants be used in furniture. After realizing their toxicity, manufacture of PBDEs in the US was banned and the levels in people are going down. However, the safety of substitute flame retardants remains an issue for further investigation.
Because of public concern about exposure to flame retardants, and a slow response from the federal government to regulate them, activist groups are focusing on state regulations. California passed a law that took effect January 1, 2016 that stopped the requirement that flame retardants be used in furniture. In April, Washington passed the Toxic-Free Kids and Families Act (ESHB 2545) that prohibits the manufacture, sale, or distribution of children's products or residential upholstered furniture containing any of five flame retardants. The law also mandates the WA Department of Ecology to investigate whether six additional flame retardants meet the criteria of a chemical of high concern for children. Here is a one page summary of the new law.
For more information about flame retardants and regulation, see the presentation slides from The Alaska Community Action on Toxics (ACAT) webinar, Toxic Safety, presented by Dr. Alissa Cordner, Assistant Professor of Sociology at Whitman College in Walla Walla, Washington. Dr. Cordner discussed flame retardant chemicals, health effects, federal and state regulation, and current activism. She presented six conceptual risk formulas distilled from stakeholder interviews.
Dr. Costa’s team's paper can be found here. Other authors include Dr. Pamela Roqué from the University of Washington and Dr. Sara Tagliaferri and Dr. Claudia Pellacani from the University of Parma. Their research was supported by the National Institute of Environmental Health Sciences Grant #ES07033.
Another summary of this research is at AASPH, the Association of Schools and Programs of Public Health > Members Research & Reports.
- Marilyn Hair