Abstract

The purpose of this study was to investigate the pollution characteristics of Seoul, Incheon, Busan, and Daegu, Korea''s large cities, which have high population density of VOCs that cause chronic damage when long-term exposure to low concentrations occurs. In Korea, there are fewer VOC studies than general air pollutants, and even fewer VOCs and CCs are measured simultaneously. The purpose of this study was to identify the emergence and concentration distribution of VOCs and to select priority management materials in metropolitan areas through regional analysis, seasonal analysis, correlation analysis, and risk assessment. This study was conducted from August 2013 to April 2017, and a total of 74 substances, including CC, were investigated.
As a result of the Seoul measurement, it was found that the traffic volume of Seoul Station in Yongsan-gu was higher than that of other points, and the three measurement areas showed similar concentration levels and different seasonal characteristics. As the concentration of commuting time tends to increase, it can be confirmed that the fluctuation of VOC concentration is a major factor in automobile exhaust gas. In Incheon, the concentration of the site affected by the mountain peak was high, and the seasonal characteristics of each material varied, and the concentrations of morning and dawn were high, and the concentrations of afternoon and after work were low. In the case of Busan and Daegu, the concentrations of branches located in industrial complexes were more than 2 to 10 times higher than those of other sites. In residential areas, the concentration at dawn was increased, and the concentration at afternoon was low, which increased with air diffusion and mixing. In industrial areas, the variation in daily fluctuations was different. The daily fluctuations of residential and industrial areas were very different, which is considered to be an effect of the characteristics of VOCs affected by the source, and thus it is necessary to classify and manage residential and industrial areas.
The trends of metropolitan areas showed different trends for each substance. The concentrations of most substances in Seoul and Incheon have decreased as of now, while Busan and Daegu have shown a decrease in some and an increase in some. Most of the results of this study compared with the harzardous air monitoring network and the overlapping data of this study. In some cases, the maximum concentration value was more than 10-fold, indicating that the data from the hazardous air monitoring network could not reflect the high concentration case. In the case of TCE in Busan and Daegu, the concentration of the monitoring network was observed higher than the results of this study, because the data of the high concentration mountainous areas were compared except for the results, which indicates that the location of the hazardous air monitoring network represents the concentration of the area. In order to prevent this phenomenon, it is considered that measurements should be made at more various positions.
As a result of multivariate analysis of VOC, hydrocarbons containing aromatic hydrocarbons, halogenated hydrocarbons, and nitrogen showed high correlations with other main components. VOC and CC are highly correlated with the different principal components, suggesting that the two groups behave independently of each other.
As a result of risk assessment, more than one substance exceeded the standard risk index, and more than 10 substances exceeded the standard risk. The cumulative carcinogenic risks in the Daegu and Busan regions were high in the carcinogenic aspects of the metropolitan area, while the cumulative noncarcinogenic risks in the Seoul area were the highest in the non-carcinogenic aspects. The cumulative carcinogenic risks in the Daegu and Busan regions were high in the carcinogenic aspects of the metropolitan area, while the cumulative noncarcinogenic risks in the Seoul area were the highest in the non-carcinogenic aspects. This means that industrial areas in Daegu and Busan, which had relatively high concentration levels in metropolitan areas, not only had high concentrations but also had a high proportion of highly toxic substances. The high level suggests that even low concentration areas require continuous observation and management.
In the metropolitan areas, DMF, epichlorohydrine, 12DCP, and acrolein were selected as priority management substances by formaldehyde and acetaldehyde in BTEX, TCE and CC. However, the results of this study confirm the importance of 12DCP, but it is not included in the air pollutant items announced by the Air Quality Preservation Act, and formaldehyde of CC is not only high in concentration but also high in the toxicity ranking of carcinogenic and non-carcinogenic aspects. Indicates. In order to manage these substances, monitoring is a prerequisite. Since the aforementioned substances and DMF are not included in the items to be measured, they need to be designated as the items to be measured later.