This BCERF Brief on polybrominated diphenyl ethers (PBDEs), a class of brominated flame retardants, includes information on their use, what products they are found in, estrogenic effects (some are estrogen mimics), rising levels in breast milk, detection in wildlife and humans, health effects, debate on the potential for the deca-form to break down, e-waste issues from electronic waste, levels in house dust, and alternatives and alternative products that do not use PBDEs.