Title: | Volatile organic compounds (VOCs) during non-haze and haze days in Shanghai: characterization and secondary organic aerosol (SOA) formation |
Author(s): | Han D; Wang Z; Cheng J; Wang Q; Chen X; Wang H; |
Address: | "School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai, China. Shanghai Environmental Monitor Center, 55 Sanjiang Road, Xuhui District, Shanghai, China. School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai, China. jpcheng@sjtu.edu.cn. Department of Civil and Environmental Engineering, National University of Singapore, 21 Lower Kent Ridge Road, Singapore, Singapore" |
Journal Title: | Environ Sci Pollut Res Int |
DOI: | 10.1007/s11356-017-9433-3 |
ISSN/ISBN: | 1614-7499 (Electronic) 0944-1344 (Linking) |
Abstract: | "To better understand the characterization and secondary organic aerosol (SOA) formation of volatile organic compounds (VOCs) during non-haze and haze days, ambient VOCs were continuously measured by a vehicle-mounted online thermal desorption system coupled with a gas chromatography-mass spectrometry (TD-GC/MS) system in Shanghai, China. The average concentrations of VOCs in haze episodes (193.2 mug m(-3)) were almost 50% higher than in non-haze periods (130.8 mug m(-3)). VOC concentrations exhibited a bi-modal pattern in the morning and evening rush hour periods on both non-haze and haze days. The ratios of toluene to benzene (T/B) and m,p-xylene to ethylbenzene (X/E) indicated that VOCs were aged air mass transported from nearby areas. The estimated SOA yields were 12.6 +/- 5.3 and 16.7 +/- 6.7 mug m(-3) for non-haze and haze days, respectively, accounting for 9.6 and 8.7% of the corresponding PM(2.5) concentrations, which were slightly underestimated. VOCs-sensitivity (VOCs-S) based on a PM(2.5)-dependent model was used to investigate the variation between VOCs and PM(2.5) concentrations in the morning rush hour. It was found that VOCs were more sensitive to PM(2.5) on clean days than during periods of heavy particulate pollution. VOCs-sensitivity was significantly correlated with the ratio of specific PM(2.5) to background PM(2.5), with a simulated equation of y = 0.84x(-0.62) (r (2) = 0.93, p < 0.001). Our findings suggest that strategies to mitigate VOC emissions and further alleviate haze episodes in Shanghai based on reducing gasoline vehicle-related sources would be very efficient" |
Keywords: | "Aerosols/analysis/*chemistry Air Pollutants/analysis/*chemistry China *Environmental Monitoring Models, Theoretical Organic Chemicals/analysis/chemistry Particulate Matter/analysis/chemistry Vehicle Emissions/analysis Volatile Organic Compounds/analysis/*;" |
Notes: | "MedlineHan, Deming Wang, Zhen Cheng, Jinping Wang, Qian Chen, Xiaojia Wang, Heling eng 21177087/National Natural Science Foundation of China/ 21577090/National Natural Science Foundation of China (CN)/ 00-16- 22988/Shanghai Environmental Protection Bureau Program/ Germany 2017/06/26 Environ Sci Pollut Res Int. 2017 Aug; 24(22):18619-18629. doi: 10.1007/s11356-017-9433-3. Epub 2017 Jun 24" |