"Estimating population exposure to benzene in Japan" 

Haruyuki Higashino, Hiroya Shinozaki, Hiroshi Yoshikado

National Institute of Advanced Industrial Science and Technology

SRA 2007 Annual Meeting (San Antonio, Texas, U.S.A. 2007/12/10)

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Abstract

Exposure assessment of benzene has been carried out in Japan, taking into account the spatial distribution of the concentration and the population by using the dispersion model we have developed. The version 2.0 of AIST-ADMER (AIST’s Atmospheric Dispersion Model for Exposure and Risk assessment) has been applied to estimate the regional distribution of concentration. The ADMER 2.0 includes the newly-developed function “sub grid module” which can estimate a distribution of concentrations at the spatial resolutions of the maximum of 100 m x 100 m within the basic ADMER grid (5 km x 5 km). The emission data, derived from the Pollutant Release and Transfer Register (PRTR) system, include estimates of annual emissions from point, non-point, and mobile sources. The largest source of benzene in Japan was automobiles. Meteorological data used for the simulation were collected from national meteorological observatories and from Automated Meteorological Data Acquisition System (AMeDAS). These data were collected in 2004 throughout the country. The simulation was performed at 364 of selected basic ADMER grids throughout Japan. Every selected grid includes one or more monitoring stations for benzene. Benzene was monitored at 418 stations throughout Japan every month in 2004. Total population of selected 364 grids was estimated to be 33 million, about a quarter of Japanese population. Estimated concentrations by the ADMER 2.0 were generally consistent with measured data. The results showed the reasonable agreements within a factor of 2 were performed at almost all monitoring stations. In case of considering background concentrations (0.5micro g/m3, derived from monitoring data analysis), 18 thousand grids of 100m x 100m throughout Japan were exceeded the Japanese environmental quality standard (3 micro g/m3), and 1.8 million people were exposed to this level. 

Keywords

benzene, exposure, model, population, grid