Levels, sources, and health risk assessment of polycyclic aromatic hydrocarbons in Brno, Czech Republic: a 5-year study.

This work aimed to determine the seasonal variations of polycyclic aromatic hydrocarbons (PAHs) in airborne PM10 at two background sites (Masná-MS, Líšeň-LN) in Brno over a 5-year period (2009-2013). Samples were collected on quartz filters using a low-volume sampler by continual filtration. Concentrations of PAHs in collected PM10 samples were determined using a gas chromatography with a mass spectrometer as a detector. A different number of PAHs were determined to be at each site, i.e., 11 PAHs at the MS site and six PAHs at the LN site, and similarities between them were identified using non-parametric analysis of variance. Potential sources were identified using principal component analysis (PCA) and PAHs diagnostic ratios. The work also focused on health risk assessment. This was estimated using toxic equivalent factors to calculate individual lifetime cancer risk, which quantifies risk of exposure to PAHs for specific age groups. The average 11-PAH concentrations in M|S site annually ranged from 19.28 ± 19.02 ng m-3 (2011) to 40.37 ± 21.35 ng m-3 (2013). With regard to the LN site, the average six-PAH concentrations annually ranged from 3.64 ± 3.87 ng m-3 (2009) and 5.27 ± 6.19 ng m-3 (2012). PCA and diagnostic ratios indicate the main sources to be traffic emissions and coal combustion. Health risk assessment showed carcinogenic risk under limit value in all cases.