BANGKOK — 15 July 2026, China’s ambassador to Thailand has pledged to forward evidence submitted by the People’s Party on cross-border water pollution to the Chinese government, after opposition MPs urged Beijing to help address toxic contamination believed to originate from mining operations in a neighbouring country.
People’s Party leader and party-list MP Natthaphong Ruengpanyawut, accompanied by Chiang Mai MP Pattharapong Leelaphat, met officials at the Chinese Embassy on Monday to present scientific findings, research and mine location data that they said demonstrate the source and extent of the pollution.
Pattharapong said he told the ambassador that the issue affects people of all nationalities and requires urgent cooperation among all countries involved. He said the submission also emphasised that toxic substances detected in northern rivers over the past year did not originate from Thailand’s natural heavy metals or activities within the country.
The documents included water and sediment test results from Thailand’s Pollution Control Department, along with research by Thanapol Penrat of Naresuan University. Pattharapong said the evidence points to contamination affecting the Kok, Sai, Ruak, Mekong and Salween rivers.
He also highlighted contamination in the Kraburi River, where arsenic and lead levels were found to exceed safety standards. According to the party, the pollution has spread through the food chain, with tests detecting excessive heavy metals in vegetables and lead contamination in fish caught from the Mekong River.
The submission also included the coordinates of 2,676 mining sites, based on data from the Stimson Center, to assist Chinese authorities in determining whether any Chinese entities are connected to the operations.
Pattharapong urged Beijing to enforce relevant Chinese laws governing rare earth management, outbound investment and export controls, and asked the Chinese government to investigate the matter and provide a written response that could be shared with the Thai public.
“We ask the Chinese government to investigate the matter and provide a written response so it can be communicated to the Thai public, demonstrating China’s commitment to resolving this issue as a founding member of the Lancang-Mekong Cooperation framework with its dedicated environmental mechanism,” he said.
He stressed that the People’s Party was not seeking to blame any particular company or country, but wanted governments involved in the mineral supply chain to jointly investigate mining operators and tackle the pollution at its source.
The party also submitted research proposing low-cost treatment methods for contaminated mine sites. According to Pattharapong, treating polluted water at operating mines would cost between 5 and 20 baht per cubic metre, while attempting to restore rivers after contamination had spread could cost hundreds or even thousands of times more and, in some cases, may prove impossible.
Pattharapong said the Chinese ambassador pledged to send all submitted documents directly to the Chinese government.
“The People’s Party will continue to closely monitor this issue until our rivers are restored and riverside communities can once again enjoy a safe environment,” he said.
