The Need for Cross-Border Collaboration to Address Arsenic Contamination in the Salween and Mekong Rivers
The Thai government must take more proactive steps to engage with Myanmar and its autonomous ethnic states to address the growing issue of cross-border pollution in the Salween and Mekong rivers. This contamination, primarily caused by mining activities, poses a serious threat to communities and ecosystems on both sides of the border.
Assoc Prof Surasak Boonrueang, an academic from the Natural Resources and Environmental Law Center at Thammasat University in Bangkok, highlights that arsenic levels in the Salween River have been found to be far above safe limits. As a result, the Sop Moei district chief in Mae Hong Son has issued a ban on using river water and consuming fish from the area.
The source of this contamination is believed to be mining operations in Karen and Shan states, where tin and rare-earth mining have long impacted the Kok and Mekong basins. However, the military government’s limited control over these regions complicates efforts to find effective solutions.
Establishing a Transboundary Environmental Impact Assessment Framework
Assoc Prof Surasak emphasized the importance of cooperation between Thailand and Myanmar to establish a Transboundary Environmental Impact Assessment (TEIA) framework. This mechanism would ensure that environmental risks are assessed and disclosed before any mining concessions are granted.
Under this framework, private operators in Myanmar would be required to disclose their activities, evaluate environmental impacts, and develop mitigation plans. It would also allow Thai agencies to monitor and respond to cross-border pollution effectively.
“Communities in both countries depend on these rivers for daily life. Transboundary impact assessments are essential to protect public health and shared ecosystems,” Assoc Prof Surasak said.
He referenced a successful TEIA pilot project between Kyrgyzstan and Kazakhstan for a copper-gold mining project as an example that Thailand could follow.
Immediate Actions and Long-Term Solutions
In the short term, Assoc Prof Surasak urged the Thai government to provide emergency assistance to affected communities and establish a unified public alert system. Currently, multiple agencies collect environmental data independently, leading to inconsistent information.
To address this, he recommended assigning the Pollution Control Department (PCD) to lead water-quality monitoring and maintain a centralized database. This would improve transparency and coordination among different stakeholders.
Thailand’s Mekong River Agreement with Laos, Cambodia, and Vietnam, where China and Myanmar are dialogue partners, could also serve as a model. The framework requires member states to notify each other of actions that may affect the river system, such as dam water releases, helping governments plan mitigation measures.
Ongoing Testing and Community Impact
Sop Moei chief Kamphan Mokthaisong announced that water and fish samples from three sites are currently undergoing retesting by the PCD and the Department of Water Resources, with results expected within seven days.
Local communities rely heavily on the Salween River for fishing, agriculture, livestock, and household use. Floating households are particularly dependent on direct river water.
Earlier tests conducted by the Health Science Research Institute at Chiang Mai University revealed arsenic levels five times above the safety standard at locations in Mae Sariang, with other heavy metals nearing unsafe thresholds. These findings raise concerns about the long-term impacts on aquatic life and local livelihoods.
Tracing the Sources of Contamination
The PCD will collaborate with the Geo-Informatics and Space Technology Development Agency to trace the possible sources of contamination. This effort aims to identify the exact origins of the pollutants and develop targeted strategies to mitigate their effects.
By strengthening cross-border cooperation and implementing robust environmental monitoring systems, Thailand and Myanmar can work together to protect the shared resources of the Salween and Mekong rivers. This collaboration is crucial not only for safeguarding public health but also for preserving the delicate ecosystems that support millions of people in the region.