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Environmental Science and Pollution Research

, Volume 26, Issue 2, pp 1857–1870 | Cite as

Spatiotemporal variation of atmospheric nitrated polycyclic aromatic hydrocarbons in semi-arid and petrochemical industrialized Lanzhou City, Northwest China

  • Panliang Liu
  • Yuanli Ju
  • Yaojie Li
  • Zhanxiang Wang
  • Xiaoxuan Mao
  • Hongmei Cao
  • Chenhui Jia
  • Tao Huang
  • Hong GaoEmail author
  • Jianmin Ma
Research Article
  • 67 Downloads

Abstract

Polyurethane foam-based passive air sampler (PUF-PAS) and passive dry deposition sampler (PAS-DD) were adopted, for the first time ever in China, to investigate the atmospheric levels and spatial-temporal distributions of air burdens and dry deposition fluxes of 12 nitrated polycyclic aromatic hydrocarbons (NPAHs) during winter and summer seasons in a multiple site field campaign in a petrochemical industrialized capital city in Northwest China. The results showed that the highest air concentration and dry deposition fluxes of ∑12NPAHs occurred at a heavy traffic site among 18 sampling sites in both winter and summer season. The lowest air concentration and dry deposition fluxes were observed at the background site. The mean concentrations of ∑12NPAHs in the ambient air were 8.6 ± 8.1 ng m−3 in winter and 15 ± 11 ng m−3 in summer. The mean dry deposition fluxes of ∑12NPAHs were 1.8 × 103 ± 1.9 × 103 ng (m2 day)−1 in winter and 1.4 × 103 ± 1.3 × 103 ng (m2 day)−1 in summer, respectively. The total concentration of 12 NPAHs was mainly dominated by 1-nitro-naphthalene (1N-NAP) and 2-nitro-naphthalene(2N-NAP) in air, accounting for 32% in winter and 45% in summer of ∑12NPAHs. 7-Nitro-benzo [a] anthracene (7N-BaA) made the largest contribution to dry deposition fluxes of ∑12NPAHs, accounting for 28% in winter and 24% in summer. The ratios of ∑12NPAHs/∑15pPAHs (parent polycyclic aromatic hydrocarbons) were calculated to identify potential sources of NPAHs across the city. The results revealed that the main atmospheric air concentration and dry deposition fluxes of 12 NPAHs could be attributed to the primary emissions in winter and the secondary reaction formation in summer. The sources of primary emissions could be traced back to petrochemical, steel mills, as well as aluminum industries in winter and vehicle exhaust in summer. Higher ∑12NPAH/∑15pPAH concentration ratios in summer indicated that the oxidation of pPAHs contributed to the secondary formation of NPAHs via atmospheric chemical reactions in this petrochemical industrialized mountain-valley city.

Keywords

Nitrated polycyclic aromatic hydrocarbons Air concentration levels Dry deposition fluxes Primary emission Secondary formation 

Notes

Acknowledgments

The monitoring data of criteria air pollutants including O3, NO, and NO2 as well as NOx were provided by the Lanzhou Environmental Monitoring Station, Gansu Province.

Funding

This research work was supported by the National Natural Science Foundation of China (grants 41671460), Natural Key R&D Program of China (2017YFC0212002), Gansu Province Science and Technology Program for Livelihood of the People (1503FCMA003), and the Fundamental Research Funds for the Central Universities (No. lzujbky-2016-258).

Supplementary material

11356_2018_3633_MOESM1_ESM.docx (496 kb)
ESM 1 (DOCX 496 kb)

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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Panliang Liu
    • 1
  • Yuanli Ju
    • 1
  • Yaojie Li
    • 1
  • Zhanxiang Wang
    • 1
  • Xiaoxuan Mao
    • 1
  • Hongmei Cao
    • 1
  • Chenhui Jia
    • 1
  • Tao Huang
    • 1
  • Hong Gao
    • 1
    Email author
  • Jianmin Ma
    • 1
    • 2
  1. 1.Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental SciencesLanzhou UniversityLanzhouChina
  2. 2.College of Urban and Environmental SciencesPeking UniversityBeijingChina

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