Quantifying the Health Risks of PM2.5-Bound Heavy Metals for Rural Populations with Different Energy Use Types During the Heating Season

Premature deaths in China due to exposure to PM2.5-bound heavy metals (HMs) are notably more prevalent in rural areas than in urban ones. In suburban rural areas, electricity and natural gas have emerged as the primary energy sources. However, in remote rural locations far from urban centers, coal and biomass are still commonly used for cooking and heating. This disparity in energy use can lead to variations in health risks among populations and may cause significant discrepancies between implemented policies and actual conditions. Winter PM(2.5 )samples were collected from rural sites across the North China Plain. To identify the effects of air exposure on rural populations with different types of energy use, we employed probabilistic and source-specific risk assessment methods. Results showed that the average PM2.5 mass was 10.08 and 10.91 times higher than the World Health Organization's recommended guideline (15 mu g/m(3)). This indicates a higher contamination burden in suburban rural areas. Children were found to be at higher risk of noncarcinogenic risks (NCR) but at a lower risk of carcinogenic risks (CR) compared to adults. Interestingly, the NCR and CR of HMs from coal and biomass combustion in remote rural areas were 2.68 and 2.47 times higher, respectively, than those in suburban rural areas. The widespread use of electricity and natural gas in suburban areas has decreased the health burden of HMs on residents when compared to the use of coal and biomass. Coal and biomass combustion was identified as the primary source of health risks in remote rural areas. In suburban rural areas, it is essential to reduce coal and biomass combustion, vehicle emissions, and industrial emissions. Our results provide valuable scientific insights for the prevention of air pollution throughout the rural energy transition process, not only in China but also in developing countries worldwide.