Analysis of the Correlation Between Heavy Metal Concentrations and Gaseous Pollutants in the Ambient Air of Cheongju

This study was conducted to evaluate the distribution characteristics of heavy metals concentrations in the ambient air of Cheongju area. The regression model for the prediction of formation characteristics and contamination degree of heavy metals by correlation analysis and regression analysis for using the multivariate statistical analysis was also established. The main wind direction was West West North (WWN) and West (W) winds, and the median concentrations of SO₂ were 0.003 ppm, NO₂ were 0.019 ppm, and CO were 0.40 ppm. Comparison of heavy metal concentrations revealed the sequence Fe>Mn>Ni>Cu>Pb>Cr>As>Cd. By the seasonal concentration variation, the concentrations of Pb, Fe and As in winter and spring showed 3.4, 2.6 and 2.2 times respectively higher than those in summer. Pb, Fe, As, Cu had a big difference by the seasonal factors, and Cr, Ni were evaluated to be influenced by the regional factors. From the results of correlation analysis, the correlation coefficient of Pb and As had 0.842 (p<0.01), which showed high correlation. And the correlation coefficients for Fe and Mn, Pb and Cu were 0.812 (p<0.01) and 0.768 (p<0.01) respectively. The gaseous pollutants SO₂ and NO₂ showed significant positive correlations with Pb, with correlation coefficients of 0.680 (p<0.01) and 0.545 (p<0.01), respectively, and exhibited significant correlations with all heavy metal components except Ni.Multiple linear regression analysis revealed that Pb was associated with SO₂ and CO, Fe with SO₂ and NO₂, and As with SO₂, CO, and WS as independent variables. The β coefficients indicated that SO₂ was a major contributing factor for the heavy metal components Pb, Cu, Mn, Cd, and As.