PM10-bound polycyclic aromatic hydrocarbons in Chiang Mai (Thailand): Seasonal variations, source identification, health risk assessment and their relationship to air-mass movement

摘要: Abstract This study aims to analyze the seasonal variations of PM10-bound polycyclic aromatic hydrocarbons (PAHs) for an estimation human health risk and identification their possible sources. Ninety four PM10 samples were collected during dry wet seasons 2010 season 2011 in Chiang Mai, Thailand, analyzed 16 PAHs by gas chromatography–mass spectrometry. The average concentrations 104.91 ± 32.70, 13.28 ± 11.34 36.24 ± 19.16 μg/m3 2010, 2011, respectively, while 16-PAHs 25.87 ± 10.13, 3.12 ± 2.18 4.58 ± 2.18 ng/m3, respectively. Correlations total relatively high all (r > 0.796). In addition, highly correlated with carcinogenic (r = 0.927) indicating that compounds dominant particulate could be generated from open burning, usually conducted season. concentration was much lower than annual past 12 years (48.17 μg/m3) because unusually amount rain precipitation low burning activity this year. According accumulated number hot spots occurring northern part approximately 19,000 found only 6,600 2011. It can seen larger scale activities performed value toxicity equivalent higher is obviously related PAHs. Diagnostic ratio principal component analysis used find out sources vehicle emission biomass main area. benzo(a)anthracene/chrysene (BaA/CHR) indicated photochemical processes long distance emissions. Findings on source relevant direction speed air mass movement run backward trajectory.