2021 Yes https://www.mdpi.com/1660-4601/18/15/7995 Suhaimi, Nur Faseeha Asia Exposure Study Students Elementary (K-5) Carbon Monoxide (CO) Particulate Matter (PM) Volatile Organic Compounds (VOCs) Nitrogen Dioxide (NO2) Traffic-related air pollution Primary schools Vulnerable population Indoor air quality Histone h3 HT schools had significantly higher PM10, PM2.5, PM1, BC, NO2, SO2, O3, CO, and TVOC than LT schools, all at p < 0.001. Children in the HT area were more likely to get higher histone H3 levels (z = −5.13). There were positive weak correlations between histone H3 level and concentrations of NO2 (r = 0.37), CO (r = 0.36), PM1 (r = 0.35), PM2.5 (r = 0.34), SO2 (r = 0.34), PM10 (r = 0.33), O3 (r = 0.33), TVOC (r = 0.25), and BC (r = 0.19). Overall, this study proposes the possible role of histone H3 modification in interpreting the effects of TRAP exposure via non-genotoxic mechanisms.