Impact of global short-term landscape fire sourced PM_2.5 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 PM_2.5), yet evidence on its health effects remains limited. Here we show that short-term exposure to LFS PM_2.5 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 PM_2.5 dataset. Each 10 μg/m³ increase in LFS PM_2.5 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 PM_2.5 in young people and the urgent need to reduce exposure and protect vulnerable populations.