Study On The PAHs Pollution And Internal Exposure Levels Of Sutdents In Guangzhou

PAHs are a kind of persistent organic pollutants which widely existing in the atmosphere, water, soil and other environmental medium. PAHs became increasingly environmental pollution problems because it can enter human body through breathing, eating, drinking even skin exposure and can make a threat to human health, such as carcinogenesis, teratogenesis and mutagenesis.This study firstly tested more than 16 kinds of PAHs in the ambient air in residential and industrial area in GuangZhou city, such as naphthalene, fluorene, phenanthrene, pyrene, etc. Secondly, we analyzed 8 kinds of OH-PAHs in the urine of elementary school students in the survey region, such as hydroxyl-naphthalene, hydroxyl-fluorene, hydroxyl-phenanthrene and hydroxyl-pyrene. This study aimed at analyzing and discussing the composition and pollution characteristics of PAHs of different regions in GuangZhou city and the influence factors to PAHs internal exposure levels of the pupils.The results showed that:(1) The average concentration levels of PAHs in the ambient air in residential area were significantly higher than that in industrial area. And the internal exposure levels of OH-PAHs in the pupil urine in residential area were slightly lower than that in industry area. The differences between concentration of PAHs in ambient air and OH-PAHs in the urine might indicate that the influence factors of the exposure levels of OH-PAHs was not only the individual breathing exposure, there were other potential exposure ways such as dietary exposure, individual differences, etc.(2) Source apportionment results showed that the pollution of PAHs in residential areas was mainly originated from traffic pollution, while the main pollution sources in industrial areas were the influence of logistics traffic, emissions of petrochemical enterprises and burning of coal and biomass.And it was concluded that the ambient air mainly included low ring PAHs(2~4 rings), such as naphthalene, acenaphthylene, fluorene, phenanthene, anthracene, fluornanthene and pyrene.While epipodium PAHs(5~6 rings) was the main enrichment in the particle phase, such as benzo [a] anthracene, chrysene, benzo [b] fluoranthene, benzo [k] fluoranthene,benzo [a] pyrene, indeno [1, 2, 3-cd] pyrene, benzo [g, h,i] perylene,and so on.(3) It showed that the correlation between OH-PAHs in residential area was significantly relevant(P< 0.01) and the correlation coefficience ranged from 0.511 to 0.928, while there was no statistical significance between 1-OHP and 1-OHN, 1-OHP and 2-OHN in industrial zone. This difference could be caused by the compound effects(logistics transportation and petrochemical enterprises) in the industrial environmental air; it also suggested that using joint monitoring of a variety of OH-PAHs can fully reflect actual exposure levels.(4) Compared with other domestic research results, the exposure levels of OH-PAHs were relatively low in GuangZhou pupils except 1-OHP in residential area, but compared with foreign studies, we should pay attention to OH-PAHs pollution in the individual exposure. In addition, the pollution of PAHs in the environmental air in the residential and industrial area in GuangZhou was at a relatively high level, it might be related to the regional pollution of Pearl River Delta.