【摘 要】
：
The atmospheric concentrations of carbonyls and BTEX (benzene,toluene,ethylbenzene,m,p-xylene and o-xylene) were measured simultaneously at a same sampling site
【机 构】
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Research Center for Eco-Environmental Sciences,Centre National de Recherche Scientifique - Institut
【基金项目】
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This work was supported by the National Natural Science Foundation of China;the National Basic Research and the Development Program (973) of China;the Special Fund for Environmental Research in the Pu
论文部分内容阅读
The atmospheric concentrations of carbonyls and BTEX (benzene,toluene,ethylbenzene,m,p-xylene and o-xylene) were measured simultaneously at a same sampling site in Beijing from September 2008 to August 2010.The average concentrations of the total measured carbonyls during autumn,winter,spring,and summer were 37.7,31.3,39.7,50.5 μg/m3,respectively,and maximal values for their diurnal variations usually happened at noontime.In contrast to carbonyls,the average concentrations of the total measured BTEX during the four seasons were 27.2,31.9,23.2,19.1 μg/m3,respectively,and minimal values for their diurnal variations always occurred in the early afternoon.The average concentration for carbonyls increased about 24％ from September 2008-August 2009 to September 2009-August 2010,for BTEX,increased about 15％.Integrated life time cancer risks for three carcinogens (benzene,formaldehyde and acetaldehyde) in Beijing exceeded the value of 1E-06,and the hazard quotient (HQ) of non-cancer risk of exposure to formaldehyde exceeded unity.
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