Weather-Specific Individual Exposure to Organic Contaminants in Fine Particulate Matter by Nontarget Screening and...

Respiration exposure evaluation to numerous organic contaminants in fine particle matter (PM_2.5) is essential for health risk characterization. There is still a lack of understanding of the individual exposure to airborne pollutants under different weathers. This study applied portable exposure samplers to collect PM_2.5 samples under hazy, precipitation, dusty, and calm weather scenarios. Non-targeted screening (NTS) based on gas chromatography-quadrupole time-of-flight mass spectrometry (GC-QTOF MS) was conducted for comprehensive identification of organic contaminants in the samples. Over 500 organic compounds were annotated and semi-quantitatively analyzed. The assessment model combining persistence-bioaccumulation-toxicity (PBT) characteristics with exposure levels was established to identify high-priority pollutants. The results indicate that the occurrence and risk characteristics of organic contaminants vary significantly under different weather scenarios with the compounds' average risk index for being highest during sandstorm weather. These findings emphasize the importance of integrating weather exposure scenarios into the complex atmospheric environment monitoring to achieve comprehensive risk assessment and provide evidence for targeted air pollution control strategies.