Observation of annual changes in concentrations of atmospheric VOCs by the collection with passive samplers (2001-2004)

Abstract

A long-term monitoring method of volatile organic compounds (VOCs), such as benzene, toluene, and xylene in the atmosphere by using passive samplers was applied to analyzing the annual changes in the concentrations of atmospheric VOCs in Kyoto City from March 2001 to December 2004. The average concentrations of ambient benzene, which were higher than the environmental criterion (3.0 μg/m 3), except for those on Mt. Daimonji in 2001, decreased to below 3.0 μg/m 3 at all sampling stations in 2004. The average concentrations of ambient toluene and xylene in 2004 were lower than those in 2001 by 1/4-1/2 times. The decrease of atmospheric VOCs concentrations in Kyoto City was evidently observed from 2001-2004. While, the average concentrations of ambient NO 2 were almost constant, or slightly increased. The decrease in ambient benzene may have been due to a decrease in the benzene content in gasoline by the end of 1999, and also by implementation of the Pollutant Release and Transfer Register (PRTR) Act in 2001. The implementation of the PRTR Act may have also affected the decrease in the atmospheric concentrations of other VOCs. Furthermore, the decrease of ambient VOCs in our institute may have been attributed to the application of the Labor, Safety and Health Law to the universities in April 2004. © 2005 The Japan Society for Analytical Chemistry.