Multi-pollutant emissions from staple crop production in China: integrated assessment of PM_2.5 pollution and associated health risks

Agricultural production is a major source of air pollutants. Although extensive studies have focused on individual air pollutants or specific agricultural production processes, integrated assessments of emissions from entire crop production processes and their related health impacts are still lacking. In this study, we developed high-resolution gridded emission inventories of six air pollutants from the six production processes for staple crops in China in 2017. The WRF-Chem model and exposure–response relationships were employed to quantify impact of PM_2.5 concentrations and the associated health risks induced by crop production. Results show that staple crop production emitted 2792.7 Gg of NH₃, 2155.5 Gg of PM_2.5, and substantial amounts of CO, SO₂, VOCs, and NOx. These emissions resulted in an annual mean PM_2.5 concentration of 1.9 μg/m³, exhibiting a spatially heterogeneous pattern with particularly elevated levels over key grain-producing regions such as the Middle–Lower Yangtze Plain, the Huang-Huai-Hai Plain, and the Northeast China Plain. Air pollutants from grain production in China were also responsible for 45,356 (95% CI 31182–59227) premature deaths in China, with approximately 80% being concentrated in key grain-producing provinces such as Henan, Anhui, and Shanxi. Straw burning, fertilizer application, and machinery operation were identified as dominant sources. These findings highlight the necessity of implementing region-specific, multi-pollutant control strategies to mitigate the environmental and health impacts of crop production.