Rivers originating in the high mountains of Asia are among the most meltwater-dependent river systems on Earth. Reducing the glacier area in the Himalayas is expected to change the land use and climate events in Asia. The Mekong, Salween, Indus, and Ganges-Brahmaputra-Meghna transboundary river basins, among others, contribute significantly to tying Asia’s rich tapestry of cultures and incredible ethnic diversity together. In this project, Southeast Asia’s main international rivers, i.e. Mekong and Salween Rivers regional water pollution were put to focus. An unexpected political crisis outbreak in Myanmar has refrained the connection thus we lost contact with the Myanmar team. Due to the unstable political environment occurred in Myanmar, the Salween River (connected from Myanmar to the boundary of Thailand) sampling plan was terminated. The main purpose of this project is to identify arsenic contamination levels in the Mekong River in the hope of helping the regional government understand the risk of As in groundwater and integrating As risks identified through climate change adaptation and disaster risk reduction into regional planning in the near future. Sampling was conducted in May and August 2022 in Cambodia and Laos, respectively. The water samples analysis including ion chromatography, inductively coupled plasma mass spectrometer (ICP-MS), and, isotope-ratio mass spectrometer (IRMS) were applied. The findings revealed that the topography of certain areas in Cambodia has exposed significantly high concentration of arsenic in groundwater compared to Laos. More research on climate change and arsenic hydrology at regional levels should be included.

IERI is one of the Climate Technology Centre and Network (CTCN) members which is the operational arm of the UNFCCC. We are actively involved in the CTCN-TA technology transfer project providing an engineering-based solution to developing countries. We are pursuing UN sustainable development goals covering clean water and sanitation, affordable and clean energy, climate action, life below water and partnerships for the goals. Through the research in this study, we promoted the regional government to include arsenic as one of the monitoring parameters in drinking water sources. The data obtained through this study has provided a precise database for appropriate climate change adaptation and mitigation strategies in regional planning especially on the clean water and sanitation sector. Therefore, we are preparing to extend the Phase I CTCN pro bono project collaboration with the Department of Climate Change, Ministry of Environment, Cambodia to Phase II where high arsenic risk villages in Cambodia based on the results obtained through this study will be targeted. We strongly support open data access for scientists worldwide to utilize the project data for future research. All information “collected/acquired and manipulated/processed” and/or “generated” as a result of this financing is publicly available. Lastly, we continuously shared the data obtained through workshops and seminar presentations.