Researchers track potentially toxic chemical derivatives in city air

Abstract

Flame-retardant chemicals found in city air around the world can transform into a soup of derivatives that are predicted to be more toxic and more persistent than their parent compounds. That’s the conclusion of a study of organophosphate ester flame retardants (OPFRs) that relies on a new framework for assessing the risks of commercial chemicals ( Nature 2021, DOI: 10.1038/s41586-021-04134-6 ). This three-step framework—which combines laboratory studies, environmental screening, and computer modeling—could be applied to other groups of mass-produced chemicals. Through reactions with light, oxygen, and other pathways, molecules in air can spawn a range of transformation products that may have properties that are very different from those of their parent. Yet these products are rarely factored into the risk assessments that underpin chemical regulation programs such as the US Toxic Substances Control Act (TSCA), often because so little is known about the derivatives. To address this, study coleader John