Thread: Cyanide contamination of water in Kok River feared, testing underway

The governor of Chiang Rai province has ordered officials at the provincial natural resources and environment office to take water samples from the Kok River, for testing for traces of cyanide.


It is reported that several Chinese companies have mining operations, particularly gold mining, in Mong Hsat, which is under the United Wa State Army’s control, about 36km from the Thai border. Cyanide is widely used in commercial gold mining.


The water in the river, which flows from Shan state in Myanmar and through Mae Ai district of Chiang Mai and Chiang Saen district of Chiang Rai, has turned murky in the past few days, raising concern among people living along the river about its safety.


The Kok River also has three tributaries, Lao, Korn and Mae Sruey.


Initial findings by environment officials show that the water quality is fine, with oxygen and pH levels within acceptable limits, but testing for contaminants will take about a month.

Cyanide contamination of water in Kok River feared, testing

Originally Posted by misskit

testing for contaminants will take about a month.

or until all the fish die. I'd take a peak but almost drowned when a truck ended in the river there 20 years back, one escape enough.I'll post any local reports.

Experts call for Myanmar talks over Thai river contamination

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.

Experts call for Myanmar talks over Thai river contamination

Full investigation into river pollution in rivers north urged

The Thai government must investigate the sources of heavy metal and arsenic contamination in two rivers north; Sai and Kok, to ensure the safety of people in the area, said Pita Limjaroenrat, chief advisor to the Progressive Movement today.


He said that the government must act quickly and hold talks with the country suspected of being responsible for the contamination.


“It is not enough for the government and provincial authorities to simply test water from the Kok and Sai rivers or restrict its use. An urgent investigation is needed,” said Pita, former leader of the now-defunct Move Forward Party, speaking in Chiang Mai.


The Kok River is a tributary of the Mekong River, which flows through Chiang Rai and Chiang Mai provinces, while the Sai River forms the natural border between Thailand’s Mae Sai and Myanmar’s Tachileik.


The contamination is believed to stem from gold mining activities in Myanmar, according to a human rights organisation in the country. It claimed that four Chinese firms are operating open-pit gold mines near the Kok River in Mong Hsai and are discharging water into local sources without proper treatment.


Meanwhile, a 45-year-old man in Chiang Mai’s Mae Ai district told Thai PBS that he is concerned about the contamination in the Kok River, saying “I run a restaurant near the Kok River and, during this month, the river is usually clear and not this murky. I assumed it might be due to natural causes.”


In March, though, after fishing in the river, he developed rashes. Normally, he said, rashes from the river go away in a few days but, this time, they lasted for more than a month.


A 14-year-old boy in the same district also developed rashes after entering the river. He went to see a doctor, but has not yet recovered.


Experts have warned that, if the problems are not solved quickly, the heavy metal residues, including arsenic, may remain in aquatic animals or vegetables irrigated with water from the rivers.

Full investigation into river pollution in rivers north urge

Food vendors on Kok River losing business due to pollution

Many venders selling food and drinks to tourists from their rafts on the Kok River, in Chiang Rai’s Muang district, are complaining that they barely had any customers over the Songkran break, which they blame on contamination of the river with arsenic and other heavy metals, discharged by upstream gold mining activities in the Shan state of Myanmar.


One of them, Suchanart Phothong, told Thai PBS reporters that she has been selling food and drinks from her raft, near the Nong Dan Bridge, for more than 30 years and claimed that, during the Songkran festival in the past few years, many tourists would visit the floating food market to eat and enjoy a dip in the river, adding that she used to earn up to 30,000 baht a day.


This year, she complains that most tourists have disappeared, because of reports that the river is polluted and officials have advised the public against using water from it.


She disclosed that several of her fellow vendors have already closed their shops and moved elsewhere, adding that she does not know how long she will remain there.


Testing of water samples taken from the river shows levels of arsenic above safe levels.


Environmental groups are urging the government to approach the Myanmar administration about tightening controls on the extensive mining activities in Shan state, which are operated by Chinese investors.

In addition to the Kok River, the Sai River, which originates in Shan State and flows through Chiang Rai, is contaminated with heavy metals.

Food vendors on Kok River losing business due to pollution

Probe urged into abnormalities found in fish from Kok River

The Living River Siam Association (LRS) and local fishermen in Chiang Saen district, of the northern province of Chiang Rai, are urging authorities to investigate whether skin diseases, found in several species of fish caught in the Kok River, are related to the arsenic and other heavy metals detected in the water.


Somkiat Khernchiangsa, president of the LRS, a campaign-based organisation working to support local communities’ rights to their water resources, disclosed that local fishermen in Chiang Saen have noticed that several species, caught in the Kok River in the past two years, have developed bumps on their skin and heads, making them wonder whether the abnormalities could be linked to the pollutants in the river.


Massive mining activities in Myanmar, for gold and other precious metals, mostly by Chinese investors, have been blamed for the discharge of waste water, contaminated with arsenic and other heavy metals, into the Kok and Sai rivers, which flow into Thailand’s Chiang Mai and Chiang Rai provinces.


Provincial authorities in Chiang Rai have forbidden the use of water from the Kok River for consumption, if samples from the river are found to contain excessive levels of arsenic.


The contamination of the river and the measures adopted by the authorities have severely affected businesses along the Kok River, such as floating food shops, forcing many of them out of business.


The LRS held a forum in Muang district of Chiang Rai on Tuesday, to address the environmental threats posed to the Kok and Sai rivers and the futures of people who are dependent on them to make a living.


The meeting concluded that there is an urgent need for dialogue between the Myanmar government, the Thai government, the ethnic Wa force and China.

Probe urged into abnormalities found in fish from Kok River

Give the uncredited AI a rest, eh.

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.

They're probably talking about the wrong neighbouring country.

Fish from Kok River confirm they are safe for consumption

Fish caught in the Kok River, in Chiang Rai province, are safe for consumption because the amount of arsenic they contain is within safe levels.


Nattharath Porndet-anan, the chief fisheries official in Chiang Rai, disclosed that recent lab tests on specimens of several species caught in the Kok River show the arsenic content averaging 0.13mg/kg, which is below the safe level of 2mg/kg. Cadmium, mercury and lead were not detected.


He admitted, however, that the number of fish in the river has declined and local fishermen are catching fewer fish because of the degradation of the ecological system, resulting in the murky river water all year round, affecting the food chain.


Nonetheless, he said that, when the river turns red during the rainy season, it means that the current has washed sediments and nutrients into the river, which benefit fish.


Massive mining activities by Chinese investors in Shan state of Myanmar, which is the source of the Kok and Sai rivers, have been blamed for contamination of the rivers with arsenic and other heavy metals. Discharges from the mining activities, which are not treated, flow directly into the rivers.


The Chiang Rai provincial administration has advised people not to use water from the Kok River for consumption, due to the arsenic contamination. Many tourism-related businesses along the river have closed down, due to a lack of customers concerned about the arsenic contamination.

Fish from Kok River confirm they are safe for consumption

Massive mining activities by Chinese investors

Now we're getting there.

Warning to kippers,

don't swallow any

'red herrings'

Kok riverbed found to contain excessive amounts of arsenic

Samples of sediment taken from the Kok riverbed, in Muang district of Chiang Rai and Mae Ai district of Chiang Mai, have been found to contain excessive amounts of arsenic, which is dangerous to aquatic species that feed on sediment.


The Chiang Mai Pollution Control Office reported on its website that it had collected samples of sediment from the Kok riverbed, at six locations in the two districts on March 31st and April 1st, for testing.


These tests show the amount of arsenic in the sediment ranges from 20mg/kg to 33mg/kg, which is beyond the safety level of 10mg/kg, reported the office, adding that excessive arsenic content threatens the ecological system of the river, endangering aquatic life.


Other heavy metals found to exceed safety levels in the sediment include nickel and chromium.


The Chiang Rai provincial administration has, however, offered public assurances that tap water, originating from the Kok River, is still safe for consumption.


Officials have been instructed, by the provincial governor, to collect specimens of fish caught in the Kok River for tests on a regular basis, to ensure that they are safe for consumption.

Kok riverbed found to contain excessive amounts of arsenic

Fish caught in arsenic-contaminated Kok River not selling

People are now reluctant to buy fish caught in the Kok River, due to reports that the river is contaminated with arsenic and other heavy metals, according to Somkiat Kuenchiangsa, President of the Living River Siam Association.


Authorities in Chiang Mai and Chiang Rai, through which the Kok River flows, have advised people to avoid using the water, following lab test results indicating that the water is contaminated.


Sediment samples, collected on March 31 and April 1 from the Kok River in Chiang Rai’s Muang and Chiang Mai’s Mae Ai districts, were found to contain arsenic levels exceeding safety standards.


Tests also detected arsenic at an average concentration of 0.13 mg/kg in fish from the river. This is, however, below the safety threshold of 2mg/kg and considered safe for consumption.


Fishermen have, though, continued to find fish with visible abnormalities. These cases are still under investigation, to determine whether they are linked to the contamination.


Similar abnormalities have been found in fish from the Mekong River, a major regional waterway, raising additional concerns about potential contamination as well, Somkiat said.


He voiced concern that fish in the Mekong are now beginning to migrate upstream, to spawn in tributaries as the rainy season approaches.


“This pollution could have a severe and widespread impact,” he warned.


The detection of toxic substances in the Kok River is very alarming, especially since fish populations were already in decline. The presence of these toxins could further disrupt their reproduction and growth.


The pollution is suspected to come from large-scale mining operations in Myanmar, reportedly backed by Chinese investors, which are believed to be discharging polluted waste water into the river untreated.


The contamination has spread to the Sai River, affecting communities in Chiang Mai province as well. Other substances found in sediment samples include nickel, chromium and cyanide.


To address the issue, Somkiat urges the Thai government to initiate a dialogue between Myanmar, ethnic armed groups and China and has proposed that the ultimate solution may be to halt mining operations in Myanmar altogether.

Fish caught in arsenic-contaminated Kok River not selling

Originally Posted by misskit

Samples of sediment taken from the Kok riverbed, in Muang district of Chiang Rai and Mae Ai district of Chiang Mai, have been found to contain excessive amounts of arsenic, which is dangerous to aquatic species that feed on sediment.

Did Silent Spring ever make it into a Thai translation?

All i can say is thank God Top Gear managed to buld the bridge over the river Kok before all this happened

Fish caught in Kok River infested with parasites and bacteria

Several species of fish caught in the Kok River in Chiang Rai province have been found to be suffering from blotches on the skin and are infested with parasites and bacteria, although traces of heavy metals, such as arsenic, were not found, according to provincial fishery officials.


The officials had collected specimens, of both carnivorous and herbivore species, from various locations in the river for testing for the second time and sent them to Chiang Mai province for analysis.


An official said that most of the fish caught were found to have red blotches on their skin, mouths, tails and fins. Lab tests show parasitic infestations and bacterial infections.


He said he expects the latest results from Chiang Mai at the end of this month.


Many residents in Chiang Rai province are avoiding eating fish caught in the Kok and Sai rivers, over fears of arsenic contamination, allegedly caused by the unregulated discharge of waste water into the rivers from gold mining activities, operated by Chinese investors in Shan state of Myanmar.


The provincial administration advises people in the province not to consume water from the rivers, but they are unable to deal with the arsenic problem, because the Shan state is controlled by several armed minority groups, such as the United Wa State Army and Myanmar government troops,

Fish caught in Kok River infested with parasites and bacteri

Tragic kok up, was a good source of healthy protein for locals farmers and hill tribes with tiny incomes.

Porbe Ordered into the Funding of Mines Polluting Chiang Rai’s Rivers

On 8 May, Mr. Rangsiman Rome, chair of the State Security, Border Affairs and National Reform committee, chaired a meeting in Chiang Rai to address arsenic contamination in the Kok and Sai rivers.


The discussion included Chiang Rai governor Charin Thongsuk, officials, academics, and civil society groups. The rivers, which flow from the Wa-controlled area in Myanmar, have been found to carry dangerous levels of pollutants into the Chiang Rai rivers.


The meeting took place at the Chiang Rai City Hall. The Kok River enters Thailand at Mae Ai district in Chiang Mai province and flows through Chiang Rai city, while the Sai River forms the border between Thailand and Myanmar.


The Office of Environmental and Pollution Control, Region 1, reported repeated detections of arsenic above safe levels (more than 0.01mg/litre) in both water and sediment samples. However, water tested in the Mae Fang tributary showed good quality, pointing to an upstream source of the pollution. Now, officials collect and test water samples twice a month.

The Chiang Rai waterworks department uses around 48,000 cubic metres of water per day from the Kok River, supplying over 41,300 people. The Mae Sai waterworks supplies 9,300 cubic metres daily to about 9,500 people, and the Ruak River provides 7,200 cubic metres daily for 5,850 users. The water is treated with chemicals to remove heavy metals and keep turbidity below safe limits, making it safe to drink.


Chiang Rai fisheries also collected fish samples—including both plant-eaters and predators—along the river to test for contamination. Some fish, like the catfish with red bumps on gills and fins, were sent for lab analysis, with results pending.


Academics from Rajamangala University of Technology Lanna suggested the source lies 8.6km and 44.9km inside Myanmar. This pollution increases arsenic levels by 15-28%, with worse contamination during the dry season.


They recommended building a water barrier in Mae Ai to trap sediment before it flows downstream.


Dr. Suebsakul Kitchanukorn from Mae Fah Luang University explained that manganese mining near the Thai border used to release wastewater straight into the Mekong River, with minerals then imported to Thailand through Mae Sai customs.


Many investors, both Thai and foreign, are involved. He urged the committee to review which groups fund the gold mines at the Kok and Sai river sources and whether any produce is exported to Thailand, so solutions can be found.
Former senator Tuenjai Deetes believes local officials have done their best, but the root of the problem lies outside Thailand. She called on the government to push for solutions, even though Thailand is not the source.


Pienporn Deetes, secretary-general of the Community Development and Mountain Area Foundation, said arsenic contamination in the Kok River is a new problem. She stressed the need to act quickly, warning of worse impacts if ignored for years.


Rangsiman Rome and his team, including Manop Kheeripuwadol (vice chair) and Yuthipong Pipoppinyoyo (secretary), announced plans to set up a working group to coordinate with provincial authorities.


They will report their findings to the government and related agencies. They also asked the Internal Security Operations Command and local Thai-Myanmar border committees to check which groups or companies have mining concessions in the Wa area. The National Intelligence Agency might be asked to help gather information for talks with Myanmar and other countries.


Yuthipong said Chinese investors are unfamiliar with the area, so they often work with influential local groups. He asked security agencies to investigate and suggested using strong measures like cutting off power and fuel supplies, as done against call centre scams.


The military will raise the issue at the upcoming Thai-Myanmar Regional Border Committee (RBC) meeting, chaired by the Third Army Region Commander, with Myanmar’s RBC. The meeting, set for 2-4 July 2025, will include the river contamination as a main agenda item to inform Myanmar authorities.

Porbe Ordered Into The Funding Of Mines Polluting Chiang Rai's Rivers