Francis Murray

Human-induced climate change is a serious development issue with major implications for agriculture, water supplies, rural livelihoods and other sectors of the economy. The Intergovernmental Panel on Climate Change (IPCC, 2007a) states that warming of the planet in unequivocal observed changes in climate are already affecting ecological, social, and economic systems, and sustainable development is threatened by climate change. Climate change may have serious consequences for the livelihoods of rural populations in the Mekong region. For rural economies in the Mekong region, the additional stresses imposed by climate change could threaten goals related to poverty alleviation. The challenges to agriculture and water supply may be further aggravated by changes in rainfall regimes, hydrology and the frequency and intensity of extreme climate events, leading to threats to economic development. Furthermore, climate change may also affect the viability of infrastructure investments such as hydropower plants. Little research has been conducted in the Mekong sub-region to understand impacts, risks, vulnerability and adaptation to climate change here. This paper considers some of the issues being investigated by a research project funded by the Asian Development Bank under the Greater Mekong Sub-region Core Environmental Program, especially focused on risks and potential adaptation measures. The project will conduct policy-relevant assessments to be discussed during workshops of government decision-makers. Some of the outcomes of this study are likely to be relevant for many countries in Southeast Asia outside of the Mekong sub-region.

A cross-sectional study of 50 participants was performed to investigate benzene exposure in an urban Mediterranean climate. Participants wore passive samplers for five 24-hour periods in each of summer and winter (including weekends), and recorded their locations and activities during sampling in a time/activity diary. Statistical analysis using a linear mixed model revealed that commuting in a private car (β= 0.281, p<0.0001) and refuelling with low benzene fuel (β = 0.194, p=0.033) were significant contributors to non-industrial personal exposure. The mean benzene exposure of the participants in summer was 1.76 μg m-3 and 1.98 μg m-3 in winter. Each hour per day spent commuting resulted in a mean increase in personal exposure of 0.74 μgm-3 (β= 0.729 μgm-3, p< 0.0001). Reported refuelling with low benzene fuel increased exposure by 1.50 μgm-3 (1.49, p<0.0001) in each 24-period when refuelling was reported. A risk assessment of these activities in Perth was conducted using the World Health Organisation unit risk model. Unit risk is a measure of the lifetime excess cancer risk posed by a lifetime exposure to a pollutant at a concentration of 1μg m-3. When applied to these two activities, the World Health Organisation risk model revealed that they pose a high risk over an individual's lifetime compared to the unit risk of 6 cases per million population exposed to 1μgm-3. The results of this research highlight the high cancer risks posed by these activities when compared to most other routine types of activities of indoor and outdoor activities that occur on a daily basis, and the need for appropriate environmental management to effectively manage and mitigate the risks these activities pose to the general public.

As part of a larger study co-ordinated in four cities by the Western Australian Department of Environmental Protection to characterise non- industrial personal exposure to Benzene, Toluene, Ethylbenzene and Xylene (BTEX), a pilot trial was conducted in Perth, Western Australia. The objectives of the pilot trial were to assess the use of passive samplers in the measurement of BTEX at a range of concentrations over 24 hours, evaluate the ease of use of a self administered questionnaire and a time/activity diary, and to trial the logistics of a conducting a personal exposure study. The results of the pilot trial indicated the questionnaire and diary effectively revealed potential lifestyle and behavioural factors that influence personal exposure to benzene. The BTEX samplers also proved effective in measuring a range of benzene concentrations, and did not limit the behaviours or activities of the participants whilst being worn.

The management of environmental issues, such as climate change and land use change, involves complex dynamics in ecology, economics and social systems. Developing integrated frameworks for these complex problems presents a challenge at all policy-making levels. Market-based policies for ecosystem services are examined with a focus on carbon sequestration, as an emerging synergy between land-use change and emissions trading of forestry-based carbon sinks, under the Kyoto Protocol. A systems-based approach offers the potential to increase our understanding of the complexity surrounding policy development for the management of multiple objectives of natural resources, within a holistic policy framework.