Polycyclic aromatic hydrocarbons (PAHs) in atmospheric PM2.5 and PM10 at a coal-based industrial city: Implication for PAH control at industrial agglomeration regions, China

- PAHs in PM2.5 and PM10 are identified for five functional sites of a coal-based city.
- PAH levels in PM2.5 for coal-chemical site are 250 times of those for background site.
- PAH compositions for PM2.5 and PM10 are different for sites with few human activities.
- Coal combustion and industrial processes may dominate the sources of PAHs in particles.

Eighteen polycyclic aromatic hydrocarbons (PAHs) in PM2.5 and PM10 are identified and quantified at five sites of E'erduosi in 2005 by GC-MS. Total PAH concentrations in PM2.5 and PM10 are in the ranges of 0.58-145.01 ng m− 3 and 5.80-180.32 ng m− 3 for the five sites, decreasing as coal-chemical base site (ZGE) > heavy industrial site (QPJ) > residential site with heavy traffic (DS) > suburban site surrounded by grassland (HJQ) > background site (QGN) for both PM2.5 and PM10. PAH concentrations in the coal-chemical base site are 250 and 31.1 times of those in the background site. Flu, Pyr, Chr, BbF, BeP, IND and BghiP are abundant for the coal-chemical base site, totally accounting for 75% of the PAH concentrations. 4, 5 and 6 rings PAHs are dominant, accounting for 88.9-94.2% and 90.5-94.1% of PAHs in PM2.5 and PM10, respectively. Combustion-derived PAH concentrations cover 42%-84% and 75%-82% of PAHs in PM2.5 and PM10, indicating large amounts of combustion sources existed for them in E'erduosi. PAH compositions between PM2.5 and PM10 are quite different from each other for sites with few human activities (HJQ and QGN) by coefficient of divergence analysis. Results obtained from principal component analysis and diagnostic ratios indicate that coal combustion, vehicle emission, wood combustion and industrial processes are the main sources for PAHs in E'erduosi. According to BaP equivalent concentration, the potential health risk of PAHs in PM2.5 at the two industrial sites ZGE and QPJ are 537 and 460 times of those for the background site. And they are 4.3 and 3.7 times of those for the residential site. The potential PAH pollution in particles at other industrial agglomeration regions that occurred in China in recent years should be paid attention by the local government.