Toxic Tide: Unregulated Mining in Myanmar Poisons Southeast Asia’s Rivers
A growing environmental crisis is unfolding along the Kok and Mekong Rivers as unchecked mining in Myanmar releases dangerous levels of arsenic and other heavy metals, threatening communities and ecosystems across Thailand and beyond.
The once-pristine waters of the Kok River, flowing from the mountains of Myanmar into Thailand’s Chiang Rai province, are now tainted. Residents first noticed a problem around two years ago, with the water becoming murky and causing skin irritation. But the situation escalated dramatically this February, when the river failed to clear during the usual dry season, revealing a far more serious issue. Testing by Thailand’s Department of Pollution Control revealed arsenic levels nearly four times the World Health Organization (WHO) limits, alongside other hazardous metals. The contamination extends to the Mekong River, Southeast Asia’s largest waterway, where unsafe arsenic levels were detected earlier this month.
“It’s not safe anymore,” says Pianporn Deetes, regional campaign director for the NGO International Rivers. “And this is the water source that people are using for irrigation, for farming, for fishing and for their cultural activities.”
The source of the pollution is widely believed to be unregulated gold and rare earth mining in Myanmar’s Shan state. The demand for rare earth minerals – essential components in everything from airplanes and electric vehicles to smartphones and military equipment – has fueled a boom in mining, largely controlled by China. This surge in activity has come with a devastating environmental cost.
Local businessman and city council member in Mae Sai, Bundit Pantarakon, points to three mines upstream on the Sai River, which borders Thailand and Myanmar. “You can see them on Google Earth,” he says. “And they use the Sai River itself to wash everything away.” He displays a rash on his hand, attributing it to toxic metals encountered while assisting in flood relief efforts in May. Subsequent testing of well water in six homes along the river revealed arsenic levels exceeding WHO limits in all but one.
The contamination isn’t limited to the Sai and Kok Rivers. The Ruak River, also feeding into the Mekong, has also shown unsafe levels of arsenic. Residents have been warned against using the water, impacting daily life and even tourism, with elephant camps refusing to allow their animals to bathe in the polluted waters.
“This is just the first chapter of the disaster that’s going to happen to the people along the Kok, along the Sai River and along the Mekong,” warns Deetes. The ongoing civil war in Myanmar is exacerbating the problem, creating a lawless environment where environmental regulations are nonexistent.
“This is the most unreported major issue in the Mekong happening now,” states Brian Eyler, who heads the Southeast Asia program at the Stimson Center in Washington, D.C. “And it’s happening upstream in Myanmar where there’s no governance. This is like the Wild West in the United States when you could go and mine anywhere without any regulation and pollute as much as you want. And there’s no one to stop them.”
The area in question is largely controlled by the United Wa State Army (UWSA), a heavily armed ethnic militia with ties to illicit activities and support from neighboring China. The UWSA declined to comment on the situation, but maps from the Shan Human Rights Foundation show a significant increase in the number of mines in recent years.
According to David Merriman, who leads the rare earths team at the market intelligence firm Project Blue, “There is trade data showing the export of rare earth products from Myanmar into China, and that’s been growing significantly in the past several years.” Estimates suggest China now imports roughly half its rare earths from Myanmar, driven in part by stricter environmental regulations within China that have prompted companies to relocate operations across the border.
While China’s direct involvement in Shan state appears limited, Merriman acknowledges its influence. “Certainly, there is influence and there is likely to have been some initial help in setting up some of these assets, but it’s not like this is a Chinese government operation having control over the outputs and such. It is controlled by the UWSA.” He adds that China’s position is essentially one of non-interference: “China is essentially saying look, this is not our problem, this is your responsibility to operate mines how you operate in your country, but we will happily buy all your product.”
The crisis deeply concerns activist Niwat Roykaew, a 2022 Goldman Environmental Prize winner who has previously campaigned against Chinese damming of the Mekong. He believes this new threat is even more alarming. “Yes, it’s a catastrophe,” Niwat says. “It’s a disaster. Because these are toxins [that get into the water] and they manifest rapidly, and affect not only humans, but also animals and vegetation and they get into the food supply.”
Niwat emphasizes that China holds the key to resolving the issue, given its influence over the UWSA. He urges Beijing to pressure the militia to adopt responsible mining practices or halt operations altogether. He acknowledges the challenge, given the global demand for rare earths, but stresses the importance of regional cooperation.
A recent statement from the Chinese embassy expressing “great importance” to the contamination and calling for “friendly dialogue” offers a glimmer of hope. Niwat confirms he has been contacted by the Chinese consulate to discuss the issue, viewing it as a positive first step. However, he remains resolute in his commitment to push for concrete action. The fate of the Mekong and the communities that depend on it hangs in the balance.
