TY - JOUR
T1 - Semi-volatile organic compounds (SVOCs) in ambient air and rainwater in a tropical environment
T2 - Concentrations and temporal and seasonal trends
AU - He, Jun
AU - Balasubramanian, Rajasekhar
N1 - Funding Information:
The authors gratefully acknowledge the financial support of this research project by the National University of Singapore and the NOAA Air Resources Laboratory (ARL) for the provision of the HYSPLIT transport and dispersion model and/or READY website ( http://www.arl.noaa.gov/ready.html ) used in this study.
PY - 2010/2
Y1 - 2010/2
N2 - The levels of a range of SVOCs (PAHs, OCPs, and PCBs) in atmospheric particulate and gaseous phases and rainwater samples were studied in Singapore from June 2007 to May 2008. Yearly average concentrations of PAHs, OCPs and PCBs in air (particle + gas) were 136.5 ng m-3, 695.8 pg m-3 and 27 pg m-3, respectively while those of PAHs and OCPs in rainwater (particulate + dissolved) were 1218.1 and 114.2 ng L-1, respectively. The lower molecular weight (LMW) PAHs were more abundant than those higher molecular weight (HMW) PAHs in rainwater. Among OCPs, HCHs were found in rainwater in relatively larger amounts than DDTs. Similar distributions patterns were also found in air samples. Statistical correlation analysis indicated that the atmospheric occurrence of SVOCs had positive correlation with ambient temperature except for particulate PAHs and negative correlations with relative humidity and wind speed; incoming solar radiation (SR) was negatively associated with PAHs, but there was almost no correlation between SR and the occurrence of OCPs and PCBs. ANOVA analysis revealed that the temporal variations were statistically significant for PAHs and PCBs in air samples and for OCPs in rainwater. In addition, local traffic emissions, trans-boundary transport of pesticides from regional sources and Aroclors 1248 and 1254 were identified as probable sources for PAHs, OCPs and PCBs in the atmosphere, respectively, based on molecular diagnostic ratios and principal component analysis (PCA) together with the assistance of air mass backward trajectories.
AB - The levels of a range of SVOCs (PAHs, OCPs, and PCBs) in atmospheric particulate and gaseous phases and rainwater samples were studied in Singapore from June 2007 to May 2008. Yearly average concentrations of PAHs, OCPs and PCBs in air (particle + gas) were 136.5 ng m-3, 695.8 pg m-3 and 27 pg m-3, respectively while those of PAHs and OCPs in rainwater (particulate + dissolved) were 1218.1 and 114.2 ng L-1, respectively. The lower molecular weight (LMW) PAHs were more abundant than those higher molecular weight (HMW) PAHs in rainwater. Among OCPs, HCHs were found in rainwater in relatively larger amounts than DDTs. Similar distributions patterns were also found in air samples. Statistical correlation analysis indicated that the atmospheric occurrence of SVOCs had positive correlation with ambient temperature except for particulate PAHs and negative correlations with relative humidity and wind speed; incoming solar radiation (SR) was negatively associated with PAHs, but there was almost no correlation between SR and the occurrence of OCPs and PCBs. ANOVA analysis revealed that the temporal variations were statistically significant for PAHs and PCBs in air samples and for OCPs in rainwater. In addition, local traffic emissions, trans-boundary transport of pesticides from regional sources and Aroclors 1248 and 1254 were identified as probable sources for PAHs, OCPs and PCBs in the atmosphere, respectively, based on molecular diagnostic ratios and principal component analysis (PCA) together with the assistance of air mass backward trajectories.
KW - Atmosphere
KW - Organochlorine pesticides
KW - Polychlorinated biphenyls
KW - Polycyclic aromatic hydrocarbons
KW - Precipitation
UR - http://www.scopus.com/inward/record.url?scp=73749086997&partnerID=8YFLogxK
U2 - 10.1016/j.chemosphere.2009.10.042
DO - 10.1016/j.chemosphere.2009.10.042
M3 - Article
C2 - 19922976
AN - SCOPUS:73749086997
SN - 0045-6535
VL - 78
SP - 742
EP - 751
JO - Chemosphere
JF - Chemosphere
IS - 6
ER -
