Indoor exposure and health risk of polycyclic aromatic hydrocarbons (PAHs) in public facilities, Korea

In the study, pollution levels of indoor polycyclic aromatic hydrocarbons (PAHs) in public facilities (vapor phase or particulate phase) were evaluated, and a health risk assessment (HRA) was carried out based on exposure scenarios. Public facilities in Korea covered by the law, including underground subway stations, funeral halls, child care facilities, internet cafes (PC-rooms), and exhibition facilities (6 locations for each type of facility, for a total of 48 locations), were investigated for indoor assessment. For the HRA, individual excess cancer risk (ECR) was estimated by applying main toxic equivalency factor (TEF) values suggested in previous studies. Among the eight public facilities, internet cafes showed the highest average PM2.5 concentration at 110.0 μg/m3 (range: 83.5-138.5 μg/m3). When assuming a risk of facility exposure time based upon the results of the surveys for each public facility, the excess cancer risk using the benzo(a)pyrene indicator assessment method was estimated to be 10-7-10-6 levels for each facility. Based on the risk associated with various TEF values, the excess cancer risk based upon the seven types cancer EPA (1993) and Malcolm & Dobson's (1994) assessment method was estimated to be 10-7-10-5 for each facility. The excess cancer risk estimated from the TEF EPA (2010) assessment was the highest: 10-7-10-4 for each facility. This is due to the 10-fold difference between the TEF of dibenzo(a,e)fluoranthene in 2010 and in 1994. The internet cafes where smoking was the clear pollutant showed the highest risk level of 10-4, which exceeded the World Health Organization's recommended risk of 1×10-6. All facilities, with the exception of internet cafes, showed a 10-6 risk level. However, when the TEFs values of the US EPA (2010) were applied, the risk of most facilities in this study exceeded 1×10-6.