Spatial and long-term temporal assessment of organic hazardous air pollutants and their comparative health risks

This study investigated the spatial and longterm temporal characteristics of 13 selected organic hazardous air pollutants and the health risks associated with inhalation exposure over a recent 6-year period. Regional types selected for this study included a residential–commercial complex, traffic junction, petrochemical industry, iron and metal industry, and background areas in Korea. Toluene was generally the most abundant pollutants in all areas. The petrochemical industrial area had the highest median concentrations of six pollutants (benzene, ethyl benzene, o-xylene, m,p-xylene, styrene, and chloroform), followed by the residential–commercial complex, traffic junction, iron and metal industry, and background area. The residential–commercial complex and traffic junction areas showed the highest and second highest toluene concentrations, respectively. Two pollutants (1,1-dichloroethane and 1,3-butadiene) were present in similar concentrations among the five areas. In addition, the temporal trends in the annual mean concentrations exhibited unpredictable behavior depending on both the area and the type of pollutants. At the residential–commercial complex and traffic junction areas, six aromatic compounds showed significant correlations among themselves. In most cases, three important meteorological parameters (relative humidity, temperature, and wind speed) were not significantly correlated with ambient pollutant concentrations. Benzene was the only pollutant that exceeded the cancer risk levels of 1 × 10^-6, and this excess was only observed at certain areas.

Keywords
Residential–commercial; Traffic junction; Petrochemical; Iron and metal; Long-term characteristics; Meteorological parameters