Health risk assessment of China's main air pollutants

With the rapid development of China's economy, air pollution has attracted public concern because of its harmful effects on health.

The source apportioning of air pollution, the spatial distribution characteristics, and the relationship between atmospheric contamination, and the risk of exposure were explored. The in situ daily concentrations of the principal air pollutants (PM_2.5, PM₁₀, SO₂, NO₂, CO and O₃) were obtained from 188 main cities with many continuous air-monitoring stations across China (2014 and 2015).

The results indicate positive correlations between PM_2.5 and SO₂ (R ² = 0.395/0.404, P < 0.0001), CO (R ² = 0.187/0.365, P < 0.0001), and NO₂ (R ² = 0.447/0.533, P < 0.0001), but weak correlations with O₃ (P > 0.05) for both 2014 and 2015. Additionally, a significant relationship between SO₂, NO_2, and CO was discovered using regression analysis (P < 0.0001), indicating that the origin of air pollutants is likely to be vehicle exhaust, coal consumption, and biomass open-burning. For the spatial pattern of air pollutants, we found that the highest concentration of SO₂, NO_2, and CO were mainly distributed in north China (Beijing-Tianjin-Hebei regions), Shandong, Shanxi and Henan provinces, part of Xinjiang and central Inner Mongolia (2014 and 2015).

The highest concentration and risk of PM_2.5 was observed in the Beijing-Tianjin-Hebei economic belts, and Shandong, Henan, Shanxi, Hubei and Anhui provinces. Nevertheless, the highest concentration of O₃ was irregularly distributed in most areas of China. A high-risk distribution of PM₁₀, SO₂ and NO₂ was also observed in these regions, with the high risk of PM₁₀ and NO₂ observed in the Hebei and Shandong province, and high-risk of PM₁₀ in Urumchi. The high-risk of NO₂ distributed in Beijing-Yangtze River Delta region-Pearl River Delta region-central. Although atmospheric contamination slightly improved in 2015 compared to 2014, humanity faces the challenge of reducing the environmental and public health effects of air pollution by altering the present mode of growth to achieve sustainable social and economic development.