Characterization, source apportionment, air/plant partitioning and cancer risk assessment of atmospheric PAHs measured with tree components and passive air sampler

• Published in: Environmental research 2021-03, Vol.194, p.110508, Article 110508
• Main Authors: Sari, Mehmet Ferhat, Esen, Fatma, Tasdemir, Yücel
• Format: Article
• Language: English
• Subjects: Adult; Air Pollutants - analysis; Air-bark partitioning; Biomonitoring; Child; Child, Preschool; Environmental Monitoring; Humans; Infant; Neoplasms; Olive tree; Polycyclic Aromatic Hydrocarbons - analysis; Ring distribution; Risk Assessment; Seasons; Semi-rural site; Trees
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2020.110508

In this study, ambient air and olive tree components (leaf and branch) were simultaneously collected and analyzed for polycyclic aromatic hydrocarbons (PAHs) to investigate their levels and accumulations, temporal variations, possible sources, air-plant partitioning and cancer risks for 12 months. During the sampling period, total of 14 PAH (∑14PAH) concentrations measured in the olive leaves (dissolved and particle phase) and braches (1- and 2-year-old) were 593 ± 472, 81 ± 67, 558 ± 273 and 316 ± 213 ng/g dry weight (DW), respectively. Similarly, the average ∑14PAH concentrations measured in the ambient air was found to be 15 ± 16 ng/m3. Generally, 4-, 5- and 6- ring PAHs were the dominant groups for all tree components, while 2- and 3-ring PAHs were predominant in the air samples. Ring distributions and molecular diagnosis ratios were employed to determine PAH sources in the sampling site. Petroleum and combustion-related sources were found to be important. The Pearson correlation coefficient was allowed to figure out the affinity between PAH levels in the sampling materials and meteorological factors. Temperature and mixing layer height were found to be effective factors on the concentrations. Atmospheric PAH levels were also predicted to employ a bark-air exchange model for determining the PAH movement direction. The predicted/measured ratios were above 1.0. This was probably due to utilizing the branch values rather than bark values in the model. Finally, the risk of cancer has been evaluated. The calculated cancer risks via inhalation were at low levels for adults and children. [Display omitted] •Tree components were successfully used to monitor atmospheric PAH concentrations.•The bark-air partitioning coefficient was utilized in the branch-air partitioning.•LMW and HMW PAHs predominated in ambient air and in tree components, respectively.•Grass, wood and coal combustions were dominant sources of PAH in all samples.•PAH concentrations in ambient air were 16 times higher in winter than in summer.