Estimating non-carcinogenic health risk of ambient PM₂.₅ and environmental determinants in palembang: An ecological study

Objective: Ambient PM₂.₅ pollution from episodic biomass burning poses persistent public health challenges in fire-prone equatorial cities, yet integrated evidence on environmental determinants and non-carcinogenic health risks at the population level remains scarce. This study estimated non-carcinogenic health risks of ambient PM₂.₅ exposure and identified contributing environmental determinants in Palembang, Indonesia, using monitoring data from 2021–2023.Methods: An ecological study was conducted using secondary monthly data on ambient PM₂.₅ concentrations from BMKG routine monitoring, meteorological variables, forest and land fire occurrences, and reported acute respiratory infection (ARI) cases. Inhalation intake was estimated using standard exposure parameters differentiated for adults and children. Non-carcinogenic risk was characterized using the Risk Quotient (RQ). Spearman rank correlation was applied following confirmation of non-normal distributions. Results: Annual PM₂.₅ concentrations exceeded both the Indonesian national standard (15 µg/m³) and WHO Global Air Quality Guidelines (5 µg/m³) across all study years, with the highest level in 2023 (45.86 µg/m³). PM₂.₅ was significantly correlated with temperature, relative humidity, rainfall, and fire occurrences (p<0.05). No significant PM₂.₅- ARI association was observed in 2021 or 2022; a moderate positive correlation emerged in 2023 (r=0.629, p=0.028). RQ exceeded 1 for both adults and children across all years, with the highest value recorded for children in 2023 (RQ=5.86).Conclusion: PM₂.₅ in Palembang consistently exceeded health-based thresholds, with non-carcinogenic risk driven by meteorological variability and episodic fire activity. Children represent the most vulnerable subgroup requiring prioritized protection. These findings provide evidence to support integrated air quality management and targeted public health interventions in fire-prone equatorial cities.