Identifying chemical groups for biomonitoring

Abstract

Regulatory agencies face daunting challenges identifying emerging chemical hazards because of the large number of chemi‑cals in commerce and limited data on exposure and toxicology. Evaluating one chemical at a time is inefficient and can lead to replace‑ment with uncharacterized chemicals or chemicals with structural features already linked to toxicity. The Office of Environmental Health Hazard Assessment (OEHHA) has developed a process for construct‑ing and assessing chemical groups for potential biomonitoring in California. We screen for chemicals with significant exposure potential and propose possible chemical groups, based on structure and function. To support formal consideration of these groups by Biomonitoring California’s Scientific Guidance Panel, we conduct a detailed review of exposure and toxicity data and examine the likelihood of detec‑tion in biological samples. To date, 12 chemical groups have been constructed and added to the pool of chemicals that can be selected for Biomonitoring California studies, including p, p´‑bisphenols, bro‑minated and chlorinated organic compounds used as flame retardants, non‑halogenated aromatic phosphates, and synthetic polycyclic musks. Evaluating chemical groups, rather than individual chemicals, is an efficient way to respond to shifts in chemical use and the emergence of new chemicals. This strategy can enable earlier identification of important chemicals for monitoring and intervention.