Lately, human health risks of chemicals are assessed in Japan. However, due to limited information regarding hazard and exposure for a large number of chemicals, only a limited number of them have been assessed to date. Existing exposure assessment procedure based on monitoring data is not applicable to many chemicals. We, therefore, developed a mathematical modeling approach to estimate site-specific concentrations of hydrophobic and low volatile chemicals in respective agricultural and livestock products based on uniquely-derived concentration correction factors and geographic information system analysis. The estimated site-specific concentrations of Di (2-ethylhexyl) phthalate (DEHP) in 3 types of agricultural products and 3 types of livestock products were in good agreement with those measured within a factor of 8. These results suggested that the developed modeling approach is applicable for estimating site-specific concentrations of hydrophobic chemicals in respective agricultural and livestock products appropriately.

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The wood preservative CCA has been applied widely in Japan since about 40 years ago, and CCA wood waste now creates severe environmental problems. Sufficient information on the effects of CCA on soil, water, and plants is not available. We investigated the contents and fractionation of Cr, Cu, and As in soils and plants around a shed in which a CCA-treated wood had been stored.
All soils collected in the shed contained higher levels of Cr, Cu, and As than a control soil. One sample from a site where CCA-treated wood had been burned showed extremely high Cr, Cu, and As contents (3450, 2310 and 830 mg kg^-1, respectively). Sequential extraction of this sample indicated that approximately 14%and 50% of As,4% and 66% of Cu occurred in soluble and mobile fractions, respectively, suggesting easy leaching. Cr was less mobile than As and Cu, 95.5% of the total content found in residual fraction. Two plant samples contained between 2.3 and 7.2 times as much Cr, Cu, and As as a control plant. We conclude that the inadequate treatment of CCA-containing wood waste such as storage or burning in an open environment might cause pollution of soils, water, and plants.

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A new method was developed to determine the roadway locations having high concentrations of benzene due to automobile emissions in the main routes of a city. Firstly, the average emission factor of benzene from gasoline vehicles was estimated by directly sampling the exhaust gases from the running vehicles by using an in-vehicle type exhaust gas sampler. Subsequently, a roadway model was developed by parameterizing the geometry of roads and buildings. By using computational fluid dynamics analysis in the roadway model, an approximate equation to calculate the roadside benzene concentrations was derived as the function of road and building parameters. Furthermore, roadway locations having high concentrations of benzene in the 150 highway routes of Osaka City were screened. The number of locations where the weekday daytime average concentration of benzene may exceed 10μg/m³ was about 2% of the total roadway locations. Although the actual conditions at the locations may not have been necessarily reflected in the simplified roadway model, the screened locations do possess a high possibility of high benzene concentration. If necessary, the actual locations having high concentration of benzene can be found by scrutinizing the roadway geometry with visual tools such as aerial photographs.

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City air pollution is both an old and new problem. Many cities in developed countries experienced severe air pollution caused by pollutants such as sulfur dioxide released at the beginning of their economic development. Although the discharge of such pollutants has fallen conspicuously in recent years, increased density of city traffic has created a new problem with an increase in pollutants such as nitrogen oxides released by cars. The various atmospheric environmental problems faced so far by developed nations are also beginning to occur in developing countries as they undergo rapid urbanization. What kinds of antipollution lessons should a developing country learn from the antipollution history of developed countries in order to improve the atmospheric environment of its cities while continuing to grow economically? In this study, we used environmental Kuznets curves to analyze sulfur dioxide and nitrogen dioxide air pollution in Beijing, where the Olympics will be held in 2008, and compared strategies and air pollution countermeasures of Beijing with those of other cities in developed countries that have hosted the Olympics. With sulfur dioxide, a change in the environmental Kuznets curve was observed for each city. With nitrogen dioxide, such a tendency was not seen in developed countries because of the delay in deploying countermeasures. On the other hand, a reduction was seen in developing cities because measures against nitrogen dioxide were taken on at an early stage. Confirmation of the environmental Kuznets curves hypothesis is not available for the observed NO₂-trend, but the analysis based on the premise suggests that learning from the experiences of developed countries can lead to the improvement of the atmospheric environment of developing countries in a way that is compatible with economic development.

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Recently, researches start to analyze subjective happiness index. This study examines the effect of environmental protection on happiness after eliminating the effect of economic factor such as Gross domestic products and unemployment. We analyze four environmental indices: local pollutants of suspended particulate matters (PM10) and sulfur dioxide (SO₂) and global environmental indices of energy use and carbon dioxide. The result implies that only the deterioration of pollution level of PM10 and SO₂ have a negative effect on happiness, and reduction of these pollutants contribute to improve happiness.

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