INVESTIGATION ON EMISSION SOURCES AND RISK ASSESSMENT OF POLYCYCLIC AROMATIC HYDROCARBONS IN THE INDUSTRIAL CITY OF ULSAN, SOUTH KOREA

Abstract

Ulsan, one of the largest industrial cities in South Korea, is famous for petrochemical, automobile, non-ferrous, and shipbuilding industries. Because of these various industrial activities, environmental pollution has been a major issue in Ulsan. It is expected that large amounts of polycyclic aromatic hydrocarbon (PAHs) have been emitted from industrial activities in Ulsan. However, little effort has been found putting on assessment and monitoring risk of PAHs in the multimedia environment.

In this study, multimedia samples (soil: 25 sites, river: 18 sites, air: 20 sites) were collected to investigate emission sources and to access the risk of PAHs. The sampling sites can be classified into three groups: rural, urban, and industrial sites. The concentrations of sixteen US-EPA priority PAHs were analyzed using a gas chromatograph/mass spectrometer (GC/MS).

For a source identification, various diagnostic ratios, principal component analysis, and positive matrix factorization were conducted. In addition, the assessment of risk of exposure via a range of pathways such as inhalation, ingestion, and dermal contact was conducted. To calculate the risk level, direct calculation and the Monte Carlo simulation were conducted.

The results of the investigation on the levels and patterns and source identification of PAHs revealed that, vehicles and industrial complexes were major sources of PAHs in Ulsan. All monitoring results indicated that the risk caused by PAH in Ulsan was at safety level suggested by the World Health Organization (WHO). In which, industrial areas had higher potential risk compare to rural/urban areas. Therefore, continuous monitoring of the Ulsan atmosphere is required.

In addition, the multimedia fate model for benzo (a) pyrene (BaP) was conducted using the ChemCAN model developed by the Centre for Environmental Modelling and Chemistry (CEMC) in Canada. As a result of the model, the fate of BaP in multimedia of Ulsan was figured out the concentration and amount of BaP were predicted based on various scenarios.

On the basis of this study, it could be possible to understand seasonal level, spatial distribution, emission source, risk levels, and the fate of PAH in Ulsan. This study can support the establishment of related environmental policy in industrial cities.