Two Chiang Mai children found with high arsenic levels linked to river fish consumption

Two children in Mae Ai district, Chiang Mai, were found to have unusually high levels of arsenic in their bodies. The children, aged 2 and 6, were regular consumers of fish from the Kok River, which flows from Shan State, Myanmar, into Thailand.

On Monday, Transborder News reported that the Chiang Mai Provincial Public Health Office had received results from heavy metal screenings of four villagers from Kaeng Sai Mun village, located at the source of the Kok River. The urine samples, collected on 19 May 2025, revealed the alarming arsenic levels in the children.According to a source, although the test results were available some time ago, local authorities chose not to release the information immediately.

Although the Chiang Mai Provincial Public Health Office requested more details from Mae Ai district, provincial authorities pressured the district office, instructing the headmen of Kaeng Sai Mun village to keep the matter from the media to prevent panic among villagers.

A source indicated that, aside from arsenic, other heavy metals such as lead and manganese were also detected above safe limits in the Kok River, though previous tests have primarily focused on arsenic. 

The local public health office has been advised to extend its testing to include blood samples from residents in at-risk areas to detect lead and manganese.

"Currently, both the village headmen and local organisations are feeling stressed due to pressure from both provincial and district authorities, who are trying to downplay the impact of the toxins in the Kok River," a source said.

“Despite the significant effects on villagers, including issues with drinking water, food, and agricultural crops, the government has no systematic plan to address the problem. This has caused considerable discomfort among the villagers. Even attempting to protest has become impossible, as the authorities have issued a ban.”

Samadul Utcharoen, a Chiang Mai MP from the People’s Party, voiced his concerns over the lack of transparency in the situation.

He stressed that the government should immediately inform the public to help them protect themselves from further harm. He also called for comprehensive health checks along the Kok River, especially for high-risk groups, and for a plan to address and compensate those affected by the contamination.

Samadul pointed out that it had been three months since local complaints led to an investigation into heavy metals in the river, with no clear progress on resolving the issue. He urged the government to declare the Kok River area a disaster zone to ensure affected communities receive the help they need.

He also raised concerns about the safety of underground water sources in the area, as many villagers are sceptical about using water from shallow wells, even after tests have been conducted.

Samadul emphasised the need for the government to develop a water treatment plan for local residents.



Sathien Chantha, a lecturer from Chiang Rai Rajabhat University, echoed the MP's views, stating that the presence of arsenic in humans indicates serious contamination.

He criticised the government for withholding information out of fear of public panic, arguing that villagers have a right to know about the risks they face so they can take appropriate action.

He called on government agencies to accelerate efforts to address the health, agricultural, and fishing risks posed by the contamination and to stop covering up the problem due to political pressure.

(2025/07/08-00:00)