Children’s respiratory hospitalizations linked to short-term air pollution exposure in Peninsular Malaysia’s urban areas

Urban air pollution is a major global health issue for children. While air pollution is linked to respiratory hospitalizations, the relationship between ambient air pollutants and schoolchildren’s health remains unclear. This study examined the short-term impact of air pollution on respiratory hospitalizations among schoolchildren (aged 7–12) in urbanized areas of Peninsular Malaysia (2018–2020). A Quasi-Poisson Generalized Linear Model (GLM) combined with Distributed Lag Non-linear Model (DLNM) was applied to daily hospital admission data and ambient air quality data (SO2, NO2, O3, CO, PM10, PM2.5, benzene, toluene, ethylbenzene, and xylene) from the Department of Environment Malaysia at five air monitoring stations (ST1: Seberang Jaya; ST2: Cheras; ST3: Shah Alam; ST4: Malacca City; ST5: Kuala Terengganu). At ST1, a 10 µg/m3 increase in pollutant levels was significantly associated (p < 0.05) with children’s hospitalizations, with the highest relative risks (RR) observed at lag 3 for benzene (RR = 1.091), lag 0 for PM10 (RR = 1.134), and lag 6 for SO2 (RR = 1.331). At ST3, toluene (RR = 1.256), PM2.5 (RR = 1.121), and PM10 (RR = 1.092) showed significant immediate effects at lag 0. At ST4, NO2 was significantly associated at lag 6 (RR = 1.124). For cumulative–lag effect, benzene (RR = 1.834) and PM10 (RR = 1.883) at ST1 were significant at lag 06; while toluene (RR = 1.291) at lag 01 for ST4. The findings indicate both immediate and delayed respiratory effects of specific pollutants in children. Urban policymakers must implement targeted actions including low-emission school zones, stringent industrial discharge controls, and enhanced haze protocols to protect children’s respiratory health in urban settings.