Effect of atmospheric humic-like substances on the behavior of hazardous organic pollutants and heavy metals in the atmosphere

2004年至2006年在日本东京西部的日野市对露水、雨水和环境空气中可能对人体有害和/或导致臭氧和二次粒子形成的氯代烃（CHs）和单环芳烃（MAH）进行了同步采样。露水中甲烷的含量低于甲烷。在露水中测定的11种挥发性有机物中，除二氯甲烷（VWM：1.14μM，n= 49）含量异常高外，甲苯（VWM：4.77nM，样品数n=49）和间，对二甲苯（VWM：5.07nM，n = 49）含量较高。氯仿，四氯化碳，1，2-二氯乙烷，苯在研究期间的露水中没有检测到。露水和雨水中的挥发性有机化合物含量高于环境气相浓度和温度校正后的亨利定律常数。河水中腐殖物质的测定方法 ...更多信息 er proposed by Hiraide，et. al.（1994），测得露水中可溶性腐殖酸和氟代酸的VWM分别为1.00mg/L和0.87mg/L（n=20），而颗粒腐殖酸和氟代酸的VWM分别为0.61mg/L和0.42mg/L（n=20）。表面张力随露水中富里酸含量的增加而降低，表明分子量相对较低且易溶于酸性溶液的类腐殖酸是露水中有效的表面活性物种。除苯外，其他主要有机物的富集因子均大于10^2，且随总HULIS浓度（溶解态和颗粒态腐殖酸和富里酸的总和）的增加而增加，HULIS浓度以露水中总无机离子浓度归一化。我们的研究结果表明，总HULIS，即腐殖酸和富里酸馏分存在于溶解和颗粒形式，在露水中可以提高大气挥发性有机化合物溶解成露珠。少

Simultaneous sampling of chlorinated hydrocarbons(CHs) and monocyclic aromatic hydrocarbons(MAHs), which could be harmful to humans and/or responsible for the formation of ozone and secondary particles, in dew and rainwater and in the ambient air was performed from 2004 to 2006 in Hino City, which is located in western part of Tokyo, Japan. CHs were less contained in dew water than MAHs. Toluene(volume-weighted mean concentration, VWM : 4.77nM, sample number, n=49) and m, p-Xylene(VWM : 5.07nM, n=49) except dichloromethane, which was abnormally high(VWM : 1.14μM, n=49), were abundant among eleven VOCs determined in dew water. Chloroform, carbon tetrachloride, 1, 2-dichloroethane, and benzene were not detected in dew water during the study period. Dew and rainwater contained higher amounts of VOCs than would have been expected from the ambient gas-phase concentrations and the temperature-corrected Henry's law constants. Following the determination method of humic substances in river wat … More er proposed by Hiraide, et. al.(1994), the VWM of soluble humic and fluvic acid fractions in dew water was found to be 1.00mg/L and 0.87mg/L(n=20), respectively, while the VWM of particulate humic and fluvic acid fractions was found to be 0.61mg/L and 0.42mg/L(n=20), respectively. Surface tension decreased with the increase of dissolved fulvic acid fraction in dew water, indicating that humic-like substances with relatively lower molecular weight, which is soluble in acid solution, could be effective surface-active species within dew water. The enrichment factors, which were defined as the ratio of the observed VOCs concentration to the estimated, were over 10^2 for MAHs except benzene and increased as the increment of total HULIS concentration(the sum of humic and fulvic acid fractions in both dissolved and particulate form) normalized by total inorganic ion concentration in dew water. Our results indicate that total HULIS, i.e. both humic and fulvic acid fractions present in both dissolved and particulate form, in dew water could enhance the dissolution of atmospheric VOCs into dew droplets. Less