The relationship between the diffusion of bio-based plastics and the crop demand for their production was analyzed, and its impacts on food insecurity in developing regions were evaluated until 2050 based on the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES). The present study has shown the following results: (1) the world plastic demand is 230 million tons in 2009 and will rise to 831 million tons in the A2r scenario, 1,211 million tons in the B1 scenario, and 1,070 million tons in the B2 scenario in 2050, and almost all of the increased demand will arise from developing regions; (2) the crop demands for bio-based plastics will be 112 million tons to 1,101 million tons for maize and 416 million tons to 4,095 million tons for sugarcane, assuming that the share of bio-based plastics in the plastic market will expand from 8 percent to 62 percent in 2050; (3) these maximum values exceed the crop production for food use, namely, 959 million tons of maize and 1,966 million tons of sugarcane; (4) even under the low diffusion scenarios, the growing demand for bio-based plastics will affect food insecurity in low-income countries because poverty will remain the primary cause of hunger in the future; and (5) criteria for the sustainable production and use of bio-based plastics needs to be developed in a similar manner to those for biofuels, which have already been reported from international organizations.

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In this research we empirically examined how the experience of hearing opinions that are skeptical about environmental problems affects pro-environmental behavior.
Hypothesis1. “There are significant interaction effects between hearing opinions being skeptical about environmental problems and the involvement in environmental problems on criticized pro-environmental behavior”
1-a. “When the involvement in environmental problems is higher, the more people hear opinions being skeptical about environmental problems, the less people address criticized pro-environmental behavior”
1-b. “When the involvement in environmental problems is lower, hearing opinions being skeptical about environmental problems does not affect criticized pro-environmental behavior“
Hypothesis2. ”There is no interaction effect between hearing skeptical opinions and the involvement in environmental problems on non-criticized pro-environmental behavior”
We conducted a mail survey in 2009 at Itabashi ward, Tokyo. The results showed that there were significant interaction effects between hearing skeptical opinions and the involvement in environmental problems on criticized pro-environmental behavior (support Hypothesis1-a, did not support Hypothesis1-b), while there were neither main effect nor interaction effect on non-criticized pro-environmental behavior (support Hypothesis2).

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Before the permanent introduction of biofuel, ethyl-tert-butyl ether (ETBE) in 2010, we assessed human health risk of ETBE via inhalatory route. The atmospheric emissions from refineries, oil tanks and fuel tanks of vehicles were estimated based on existing emission data on gasoline components and statistical data on vehicles. Based on the estimated emission, the spatial distribution of atmospheric concentrations of ETBE in Japan was estimated by using an atmospheric model at a 5 km × 5 km spatial resolution. In parallel with the exposure assessment, non-observed adverse effect level was determined from results of 13 weeks inhalation toxicity study. Human health risk due to inhalation of ETBE was characterized by comparing margin of exposure (MOE) with a product of uncertainty factors. The result shows human health risk of ETBE via inhalatory route is not at a level of concern.

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The objectives of this paper are to assess consumers′ price premium for ecosystem- and environment-friendly rice compared to conventionally grown rice, and to investigate factors affecting that premium. In our questionnaire survey conducted in Japan, consumers′ willingness to pay for such rice was elicited using an open-ended format, after they were informed about farming practices for producing the rice. The analysis split the price premium into two aspects, ecosystem and environment, corresponding to consumers′ assessments for that style of farming. The results reveal that consumers tend to show a certain willingness to pay an ecosystem premium, which is higher than the environmental one, and demographic variables, consumers′ knowledge, time preference and risk attitudes are determinants of the individual ecosystem premium.

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Sewage sludge is the residual material resulting from the processing of residential and industrial waste. Groundwater contamination, caused by low quality processing of sewage sludge, is regarded as a serious problem demanding a readily available, cost effective and practical method for its monitoring. Electrical Conductivity (EC) is currently being used in many situations to monitor groundwater and has proven to be effective. Few studies however have sought to clearly determine upper limits of EC for monitoring groundwater quality.
The study area is “Sanpou” Mountain located east of Nagasaki city. There is a final disposal plant atop the mountain and with homes and farms nearby. Groundwater quality tests which includes NO₃-N and EC, have been performed four times a year since 1998 for three contaminated and one control points. These points have the same natural conditions with the control site only being free from human-origin contamination.
We created a EC local limit for effective monitoring of the groundwater quality in the sites possibly contaminated by sewage sludge leachate or incinerated ash. We extended the “benchmark dose” (BMD) concept to obtain this limit by statistically analyzing the relationships between NO₃-N and EC at the control point.

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In order to assess the overall impacts of climate change on a nation and investigate effective adaptation measures, it is important to collect scientific understanding beyond academic disciplines, because impacts of climate change emerge every aspect of the society. Modeling is a widely accepted method to assess future climate change impacts: develop climate and socio-economic environment assumptions in the future (scenarios), run statistical or process based models using the scenarios, and simulate the future situation for each subject and discipline. If a large number of modelers conduct simulations using a set of common scenarios, one can obtain a multi-disciplinary national perspective of climate change impacts and potential adaptation strategy. In this study, climatic and socioeconomic scenarios for Japan were discussed for climate change impact assessment and adaptation measures investigation by reviewing earlier literatures and latest research activities. A set of scenarios were developed covering the whole Japan, utilizing available information.

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