Hexabromocyclododecane (HBCD) and similar cyclic brominated flame retardants pose unreasonable risks to workers and the environment, the US Environmental Protection Agency concludes in a final risk assessment. The agency plans to impose restrictions during the next 2 years to mitigate the risks.
Workers are at risk from the use and disposal of HBCD and similar chemicals in building and construction materials, such as polystyrene insulation, the EPA says in the final assessment, released Sept. 24. The assessment assumes that workers do not use personal protective equipment (PPE), such as respirators.
The EPA claims that the chemicals are no longer manufactured in the US, but they are found in older products and buildings.
HBCD and other cyclic aliphatic bromide flame retardants are persistent, bioaccumulative, and toxic. Exposure to the chemicals is associated with thyroid hormone changes in people. The EPA also identified risks to wildlife including reduced growth in algae, fish, and other aquatic species, and reproductive effects in earthworms.
The HBCD assessment is one of the first 10 that the EPA is wrapping up under the 2016 amendments to the Toxic Substances Control Act. The agency finalized assessments of methylene chloride and 1-bromopropane earlier this year. It expects to complete the remaining 7 by the end of 2020.
The EPA made several changes to its HBCD assessment following criticisms from its external advisory panel and environmental groups. The agency did not identify any risks in its draft evaluation of HBCD in 2019. A group of external advisors raised concerns that the EPA did not adequately address environmental concentrations of HBCD from demolition and disposal. The agency considers such uses in its final assessment.
The EPA also changed its assumption regarding workers using PPE. Previously, the agency assumed that all workers don such equipment.
Environmental groups are pleased that the EPA addressed some of their concerns related to the draft assessment but they urge the agency to do more to assess the risks to the general population and consumers. The latest HBCD assessment found no risks to the general population and consumers, despite that the chemical is found in textiles, electronics, car seats, and many other older products found in many households.