TY - JOUR
T1 - The enhanced dissolution of some chlorinated hydrocarbons and monocyclic aromatic hydrocarbons in rainwater collected in Yokohama, Japan
AU - Okochi, Hiroshi
AU - Sugimoto, Daisuke
AU - Igawa, Manabu
N1 - Funding Information:
We would like to thank many students and graduates in our laboratory for sampling and analysis and Dr. Mario Massucci in British Antarctic Survey and Prof. Peter Brimblecombe in UEA, UK for valuable comments. This work was supported in part by Core Research for Evolutional Science and Technology (1996-2001), Japanese Science and Technology Corporation.
PY - 2004/8
Y1 - 2004/8
N2 - By simultaneous sequential sampling of gas and rainwater from 1999 to 2000 in the campus of Kanagawa University in Yokohama, Japan, we investigated the wet-scavenging process of volatile organic compounds, some chlorinated hydrocarbons (CHs) and monocyclic aromatic hydrocarbons (MAHs), via rain droplets. Their volume-weighted mean concentrations in 125 rainwater were 4.98nM for dichloromethane, 3.71nM for toluene, 2.00nM for benzene, 0.93nM for 1,2-dichloroethane, 0.62nM for o-xylene, 0.57nM for m,p-xylene, 0.51nM for p-dichlorobenzene, and 0.35nM for trichloromethylene. Their rainwater concentrations did not depend on the rainfall intensity, and the temporal variation of their concentrations was similar to that of gas-phase concentrations. The dissolution of CHs and MAHs into rainwater, however, was larger than expected from their gas-phase concentrations at the ground and their temperature-corrected Henry's law constants. A simple below-cloud scavenging model, which was developed by Levine and Schwartz (Atmos. Environ. 16 (1982) 1725) could explain the independence of the rainfall intensity but not explain their enhanced dissolution in rainwater. The results of this study indicate the estimated concentrations, which were based on the Henry's law equilibrium, considerably underestimate the wet-deposition fluxes of CHs and MAHs onto the ground.
AB - By simultaneous sequential sampling of gas and rainwater from 1999 to 2000 in the campus of Kanagawa University in Yokohama, Japan, we investigated the wet-scavenging process of volatile organic compounds, some chlorinated hydrocarbons (CHs) and monocyclic aromatic hydrocarbons (MAHs), via rain droplets. Their volume-weighted mean concentrations in 125 rainwater were 4.98nM for dichloromethane, 3.71nM for toluene, 2.00nM for benzene, 0.93nM for 1,2-dichloroethane, 0.62nM for o-xylene, 0.57nM for m,p-xylene, 0.51nM for p-dichlorobenzene, and 0.35nM for trichloromethylene. Their rainwater concentrations did not depend on the rainfall intensity, and the temporal variation of their concentrations was similar to that of gas-phase concentrations. The dissolution of CHs and MAHs into rainwater, however, was larger than expected from their gas-phase concentrations at the ground and their temperature-corrected Henry's law constants. A simple below-cloud scavenging model, which was developed by Levine and Schwartz (Atmos. Environ. 16 (1982) 1725) could explain the independence of the rainfall intensity but not explain their enhanced dissolution in rainwater. The results of this study indicate the estimated concentrations, which were based on the Henry's law equilibrium, considerably underestimate the wet-deposition fluxes of CHs and MAHs onto the ground.
KW - Chlorinated hydrocarbons
KW - Henry's law
KW - Monocyclic aromatic hydrocarbons
KW - Rainwater
KW - The falling droplet approach
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U2 - 10.1016/j.atmosenv.2004.03.053
DO - 10.1016/j.atmosenv.2004.03.053
M3 - Article
AN - SCOPUS:3142604790
SN - 1352-2310
VL - 38
SP - 4403
EP - 4414
JO - Atmospheric Environment
JF - Atmospheric Environment
IS - 26
ER -