An electronic waste disposal center in Ghana. The items, likely older and coated with a flame retardant like BDE-47, are disassembled and burned without protections for workers or the environment.Photo:
Flame retardants are nearly ubiquitous in daily life and can be found in computers, chairs, and even mattresses. Although they are added for safety, one now-banned class of flame retardants called polybrominated diphenyl ethers (PBDEs) was found to be toxic to the brain, liver, and other organs. But exactly how one of these PBDEs, BDE-47, exerted its toxic effects has remained elusive, until recently.
Professor Lucio Costa in the Department of Environmental and Occupational Health Sciences found that particular types of receptors in the brain are involved in BDE-47 toxicity. These findings, published in the January 2016 issue of Toxicology Letters, help paint an increasingly detailed portrait of how BDE-47 causes toxicity in the brain. By augmenting the amount of glutamate, a neurotransmitter found throughout the brain, BDE-47 causes brain cells to become over-activated through these receptors, which can cause a chain of events culminating in cell death. This sequence of events is especially harmful to developing brains, like those in infants and toddlers, and can lead to issues such as higher impulsivity, and diminished attention and motor coordination.
Ironically, the BDE-47 problem arose from the well-intentioned desire for fire safety. “Because of the stricter fire laws,” Costa explained, the level of BDE-47 in people “in the US is about one order of magnitude higher than in Europe or Japan.” Due to a ban on the new production of PBDEs following the revelation of their toxicity, Costa reassures that “the levels are going down.” However, the safety of substitutes for BDE-47 remains an issue for further investigation.
Other authors include Pamela Roqué, a senior fellow in the University of Washington Department of Environmental and Occupational Health Sciences and Sara Tagliaferri and Claudia Pellacani from the University of Parma. The research was supported by the National Institute of Environmental Health Sciences.