Polycyclic aromatic hydrocarbons in Chinese surface soil: occurrence and distribution

Area of Science:

• Environmental Chemistry
• Soil Science
• Pollution Monitoring

Background:

• Polycyclic Aromatic Hydrocarbons (PAHs) are persistent organic pollutants with potential adverse environmental and health impacts.
• Understanding the distribution and sources of PAHs is crucial for effective environmental management in China.

Purpose of the Study:

• To comprehensively assess the national-scale pollution status of 16 PAHs in Chinese surface soils.
• To establish the spatial distribution patterns and identify potential sources of PAHs in various soil types across China.

Main Methods:

• Analysis of 16 PAHs in 157 concurrently collected soil samples from urban, rural, and background sites in China (2005).
• Correlation analysis with emission inventories to confirm PAH distribution patterns.
• Literature review (2004-2013) to establish historical spatial distribution and analyze riverbank soil pollution.

Main Results:

• Higher concentrations of total PAHs (∑16PAHs) were observed in urban soils, followed by rural and background soils.
• A primary distribution pattern of PAHs in Chinese surface soil correlated positively with emission inventories.
• PAH concentrations were higher in Eastern China compared to Middle and Western China, with riverbank soils exhibiting elevated levels.

Conclusions:

• This study provides the first comprehensive national-scale assessment of PAH pollution in Chinese surface soils based on monitoring data.
• PAH pollution in China exhibits distinct spatial patterns, influenced by emission sources and geographical factors.
• Polluted rivers represent a significant potential source contributing to elevated PAH levels in adjacent riverbank soils.