Impact of global short-term landscape fire sourced PM2.5 exposure on child cause-specific morbidity: a study in multiple countries and territories

Children are particularly vulnerable to landscape fire sourced fine particulate matter (LFS PM2.5), yet evidence on its health effects remains limited. Here we show that short-term exposure to LFS PM2.5 is associated with increased hospital admissions for multiple diseases in children and adolescents. We analysed daily hospital admission data from 1012 communities in seven countries/territories, linked to a high-resolution LFS PM2.5 dataset. Each 10 μg/m3 increase in LFS PM2.5 was associated with elevated risks for all-cause (1.1%), respiratory (1.9%), infectious (1.5%), cardiovascular (2.9%), neurological (2.8%), diabetes (3.7%), cancer (1.5%), and digestive (0.8%) hospital admissions. Risks for respiratory, infectious, and neurological conditions increased even at low exposure, while others rose only above 15-20 μg/m3. Children aged 5-9 years and those in lower socioeconomic areas were especially affected. These findings highlight the health burden of LFS PM2.5 in young people and the urgent need to reduce exposure and protect vulnerable populations.