Thailand should urgently hold talks with Myanmar and ethnic groups to seek solutions to the problem of heavy metal contamination of the Sai and Kok rivers, believed to stem from gold mining activities in Myanmar, said Chainarong Setthachua, lecturer and ecology expert at Maha Sarakham University.
He expressed concern that heavy metal residues, including arsenic, may remain in aquatic animals or vegetables irrigated with water from the rivers.
He was speaking after Senior Deputy District Chief Sitthisak Injakham revealed that tests on water samples, collected from the Sai River on February 17, showed arsenic contamination levels of 0.014 mg/L, exceeding the safety standard of 0.01 mg/L.
Sitthisak said he received the test results from February on April 10 and is still awaiting results from samples collected in March.
He added that water sampling efforts will be expanded, to include the RMC and Muang Dang branch canals.
Meanwhile, former senator Tuenjai Deetes has also called on the Thai government to begin discussions with the neighbouring country immediately, noting that the issue directly affects local residents and communities.
She stressed that cooperation with Myanmar is essential to address the contamination in both the Kok and Sai rivers.
Last week, Arveera Pakamat, director of the Environment and Pollution Control Office in Chiang Mai, said that officials had collected water samples from the Kok River in Mae Ai district on March 19th. Tests revealed arsenic levels at twice the acceptable standard.
These samples from the Kok River contained 0.026 mg/L, posing a health risk, Arveera said.
He also noted that the water in the river is currently about nine times cloudier than normal and that other heavy metals, such as cadmium and lead, were also detected.
In Chiang Rai province, residents have been advised not to consume water from the Kok River.
According to a human rights organisation in Myanmar, there were no gold mining operations in Shan State until 2020, when
Chinese companies began prospecting for the precious metal.
Currently, four Chinese companies are operating open-pit gold mines near the Kok River in Mong Hsai, employing more than 300 Chinese nationals working around the clock.
Water used in the gold extraction process is drawn from the Kok River and discharged back into it without any treatment, the organisation claimed.
