Impact of urbanization on heavy metals in outdoor air and risk assessment: A case study in severe cold regions

Urbanization may result in an accumulation of heavy metals (HMs) in urban air ecosystems, negatively impacting air quality and potentially endangering the health of urban residents. This study utilized Jilin Province, a cold region of China, as a case study. It employed kriging interpolation to unveil heavy metal distribution, Principal Component Analysis (PCA) for source identification, and ecological and health risk assessment methods to evaluate potential health threats. The mean concentrations of HMs were greater than the local background values, indicating that heavy metal pollution in the air in Jilin Province is more serious and may be harmful to the environment and human beings. HMs tend to accumulate in urban areas with high GDP and population density and disperse to neighboring cities with levels of GDP and population density. The study identifies biomass combustion, coal combustion for heating and vehicle emissions as the primary sources of HMs. HMs in the air in Jilin Province pose a risk to both the environment and the human body, with children being particularly vulnerable. These findings emphasize the necessity of implementing comprehensive evaluation and monitoring strategies to mitigate urban air pollution and ensure environmental sustainability.