Pollution Characteristics Of Nitro-polycyclic Aromatic Hydrocarbons In Particulate Matter In Dongguan And Those Effections On Human Health

Nitro-Polycyclic aromatic hydrocarbons (NPAHs) are widespread pollutants. It is wellestablished that many of nitro-PAH are direct mutagenic, teratogenic and carcinogenic。Alongwith the development of industrialization and the increment of the car's quantity, the air particulatematter pollution and the other organic pollutants on particles become more and more serious.Developed countries had preliminary research on some of this substance.The domestic havemany research on16kinds of PAHs but rarely on the more toxic nitrated polycyclic aromatichydrocarbons in the particulate matter.Typical particle pollution were observed in Pearl RiverDelta region in china, Dongguan is one of the most serious pollution city in Pearl RiverDelta.This paper is taking Dongguan city as the research area to research atmospheric particulatepollution as well as pollution of6NPAHs (2-NF,9-NA,2-NFl,3-NFl,1-NP,2-NP) in particles.The distribution characteristics, sources of NPAHs and its hazard to human health during2010November to2012April in6different areas of Dongguan and a tunnel environmental have beenstudied.(1) Treatment and analysis of nitrated polycyclic aromatic hydrocarbons. In order to obtainan optimum method to treat and analysis the nitrated polycyclic aromatic hydrocarbons inparticle, three kinds of extraction reagent and two kinds of extraction methods were used toestimate the efficiency of extraction. The results show that ultrasonic extraction three times withmethylene chloride as extracting reagent is the best way and adding DMSO may further improvethe extraction efficiency. Comparison of three analysis methods of nitrated polycyclic aromatichydrocarbons show that HPLC-UV can be a very good analysis method of nitrated polycyclicaromatic hydrocarbons in particulate matter.(2) Concentration and distribution (including particle size distribution, seasonal distributionand area distribution) of6kinds of NPAHs in particles were studied in this paper. The resultsshowed that concentrations of NPAHs in the spring and summer are higher than in other seasons;Content of NPAHs in Da LingShan where have a relatively high traffic intensity and Hu Men inspring are significantly higher than that in other seasons. NPAHs is mainly distribute in fineparticulate matter, especially in micron particles (<0.4um). Micron particles only accounted for1.4%of total particulate matter in Dongguan City, while the ratio of NPAHs in micron particlesranged from12%to45%in total.(3) The possible sources of PAHs and NPAHs were estimated by some specific valuecombined with meteorological conditions as well as O3, NOx, NO2concentration. The resultsshow that the nitrated polycyclic aromatic hydrocarbons mainly come from automobile exhaustand industrial emissions, in part from reaction between PAHs and NOx. The pathway for NAPHs mostly is reaction between PAHs and NO2propeled by [OH] in the presence of NO2.(4) The BaP equivalent toxicity of PAHs and NPAHs evaluated by the PEFs (PotencyEquivalency Factors) in particulate matter and the individual carcinogenicity index was using toestimate the health hazards to human. Research shows that the value of [BaPeq] range from0.45ng/m3to65.6ng/m3, and the individual carcinogenic index is in the range of0.49×10-6to7.2×10-5. The value of [BaPeq] and the individual carcinogenic index in tunnel environment ishigest. In addition to the tunnel environment, the value of [BaPeq] was not exceeding limits.Individual carcinogenic index also showed that only PAHs and NPAHs on the particle in tunnelenvironment pose a serious threat to human health.