Enrichment and transfer of polycyclic aromatic hydrocarbons (PAHs) through dust aerosol generation from soil to the air

Polycyclic aromatic hydrocarbons (PAHs) are major organic pollutants in soil. It is known that they are released to the atmosphere by wind via dust aerosol generation. However, it remains unclear how these pollutants are transferred through the air/soil interface. In this study, dust aerosols were generated in the laboratory using soils (sandy loam and loam) with various physicochemical properties. The PAH concentrations of these soils and their generated dust aerosol were measured, showing that the enrichment factors (EFs) of PAHs were affected by soil texture, PAH contamination level, molecular weight of PAH species and aerosol sizes. The PAHs with higher EFs (6.24-123.35 in dust PM2.5; 7.02-47.65 in dust PM10) usually had high molecular weights with more than four aromatic rings. In addition, the positive correlation between EFs of PAHs and the total OCaerosol content of dust aerosol in different particle sizes was also statistically significant (r = 0.440, P < 0.05). This work provides insights into the relationship between atmospheric PAHs and the contaminated soils and the transfer process of PAHs through the soil-air interface. (C) Higher Education Press 2023

Automated summary

In this study, dust aerosols were generated in the laboratory using soils with various physicochemical properties, and the concentrations of PAHs in the soils and generated dust aerosol were measured. The enrichment factors (EFs) of PAHs were found to be influenced by soil texture, PAH contamination level, molecular weight of PAH species, and aerosol sizes. PAHs with higher EFs usually had higher molecular weights. Furthermore, there was a positive correlation between EFs of PAHs in different particle sizes and the total organic carbon content of dust aerosol.