Profiling hydrophobic organic pollutants in serum from vulnerable populations in Dalian, China.

Human are exposed to synthetic chemical mixtures via multiple pathways, causing potential health risks especially for vulnerable populations. Biomonitoring studies are vital to understand the health outcomes of chemical mixtures. Yet, most existing research focused only on specific chemicals and seldom compared different vulnerable populations. Herein, we developed a high-coverage approach for comprehensive analysis of 986 hydrophobic organic pollutants (HOPs) in human serum via a GC-Orbitrap-MS. Then, we investigated the HOPs in serum from pregnant women, older adults, and children, and 204, 201, and 161 pollutants were respectively detected, including phthalate esters (PAEs) and organophosphate esters (OPEs), and polycyclic aromatic hydrocarbons (PAHs). The levels of HOPs span 7 orders of magnitude from 10-7 to 1 μM. Older adults exhibited higher concentrations for majority of the HOPs, especially for pesticides, while levels of chlorinated polycyclic aromatic hydrocarbons were higher in children serum. OPEs were significantly higher in pregnant women. The ToxPi model indicated neurotoxicity as the primary potential toxic pathway for all the three populations, and PAEs exhibited the highest priority. PAEs also showed the highest probabilistic hazard quotient (PrHQ) values for older adults and children, whereas OPEs ranked highest for pregnant women. This study reveals markedly different exposure scenarios across the life cycle, highlighting the need for population-specific pollution monitoring strategies.