Twenty-one types of vegetables and fruits along the Kok River are contaminated with heavy metals, including chili, corn, cucumber, garlic, pineapple, eggplant, mango, and yardlong beans. The Consumer Council is urging the government to establish a surveillance and risk management system for this issue.
The plants found to exceed contamination standards are commonly consumed foods such as chili, corn, cucumber, garlic, pineapple, eggplant, mango, yardlong beans, and several other vegetables and fruits. However, there is no clear information about whether these contaminated crops have been properly disposed of or where they have been transported and sold.
A toxic crisis on our plates: vegetables and fruits along the Kok River have been found contaminated with heavy metals in 21 types through six rounds of continuous testing. The Consumer Council urges the government to urgently amend the Food Act to establish a surveillance system and manage risks effectively, while providing clear information to reduce the burden on consumers to protect themselves.
According to the Consumer Organizations Council (Consumer Council), this question has become a growing concern among consumers after the Mae Ai District Agricultural Office, in collaboration with the Chiang Mai Agricultural Research and Development Center, tested agricultural products from areas along the Kok River in Mae Ai District, Chiang Mai Province. They found cadmium, lead, and arsenic contamination exceeding standards in at least 21 plant types through six rounds of testing from December 2025 to May 2026. Some plants showed contamination with more than one type of heavy metal, especially cadmium, which was consistently above limits in every round. Although the exact source of contamination remains unclear, observations suggest a connection to the Kok River and sediment in flooded agricultural soils.
What is worrisome is that the plants found with contamination above standards are everyday foods consumed by people, including chili, corn, cucumber, garlic, pineapple, eggplant, mango, yardlong beans, and various other vegetables and fruits. There is still no clear information on whether these contaminated products have been properly destroyed or where they have been transported and sold.
This situation reflects gaps in the Food Traceability system, which prevents consumers from verifying whether the food they purchase is safe or comes from a risk area.
The concern is not only the detection of contaminants but also the insufficient and unclear warning information for consumers to protect themselves. When heavy metals are found in crops, consumers should receive complete and rapid information about which products are unsafe, where they originated, and how they have been distributed in the market, so they know what to avoid.
Such information is not consistently disclosed or updated. As a result, warnings may only cause anxiety without effectively helping consumers reduce risks or protect themselves.
Ms. Prokchon Usub, Subcommittee Member on Food, Drugs, and Health Products of the Consumer Organizations Council (Consumer Council), stated that food safety issues should not be addressed only after problems arise. Instead, there must be a surveillance system capable of managing risks from start to finish. Particularly when unsafe products are found, they must be removed quickly from the market to prevent risks from reaching consumers.
The real concern is not only the detection of contaminants but also delays in testing and response after risks are identified. If test results take a long time, by the time information is confirmed and communicated to the public, the contaminated vegetables and fruits may have already been harvested, transported, and consumed.
“In this case, the test results were delayed by eight months. The contaminated vegetables and fruits have already been consumed and excreted from our bodies, but the heavy metals remain in our bodies,” she said.
When risk signs are detected, the government should not stop at testing, meetings, or memorandums of understanding. It must have rapid and concrete response plans to prevent risky products from reaching consumers.
For immediate problem-solving, if heavy metal contamination risks are confirmed, the government should not allow cultivation of edible crops in those areas to continue supplying the market. Authorities must boldly designate specific risk or control zones so that the public, farmers, buyers, and operators receive consistent information.
In risk areas, measures should be taken to suspend cultivation of edible crops and consider switching to plants suitable for soil remediation or heavy metal absorption. Academic agencies must systematically supervise and monitor this to avoid creating new forms of risk.
Simultaneously, central and local agencies must mobilize to implement concrete support plans, including providing safe drinking water and food for local people, checking whether harvested products have entered the market, and, if so, establishing mechanisms to track and swiftly remove these items from the market.
Controlling risk zones to protect consumers must go hand in hand with supporting farmers. If the government orders suspension of cultivation or sales, farmers should not bear the losses alone. Clear compensation measures for farmers' income and damages are necessary, along with support for alternative production areas or channels during soil restoration periods.
The Consumer Council believes protecting consumers must be balanced with supporting farmers, including suspending harvests, providing alternative water sources or production areas, soil testing and restoration, and systematic compensation measures to effectively break the risk cycle without burdening producers or consumers unfairly.
The Consumer Council has continuously monitored and advocated for food safety issues, especially amendments to the Food Act B.E. 2522 (1979), which has been in effect for over 40 years and is limited in handling the current food system, including post-market surveillance and product recall mechanisms.
A key issue to urgently address in the current Food Act is to establish an effective post-market surveillance system and clearly assign responsibility for product recalls to operators.
If products are found unsafe or substandard, operators should be required to notify regulatory agencies, carry out product recalls from the market, and promptly inform consumers—not leaving it solely to the government to spend budget and staff resources tracking products distributed nationwide.
These provisions are included in the Consumer Council's draft Food Act, one of three laws for which the Council has gathered over 70,000 public signatures submitted to Parliament, aiming to update laws to keep pace with changing circumstances.
Solving food safety issues long-term requires not just increasing testing frequency but transforming systems to enable risk surveillance, assessment, and management from production to consumption.
The Consumer Council's draft Food Act proposes that relevant agencies jointly develop a risk management plan to control risks throughout the food chain—from production areas, transportation, and distribution to consumers—and establish rapid warning and response systems when risks are detected.
Risk communication must be integrated into the system, not left for the public to learn from news or social media. When heavy metals are found in crops, consumers should receive complete and timely information about which products are unsafe, their origin, market distribution, and avoidance measures.
Another important proposal from the Consumer Council is transparent and easy access to food testing data because information generated using public funds should not remain confined within government agencies.
If the public and media can access data quickly, they can help monitor, alert, and reduce the risk of widespread consumption of unsafe food. Especially in cases like the Kok River contamination, people deserve clear answers about which products are risky, affected areas, and measures to prevent contaminated goods from reaching the market.
The Consumer Council calls on the government to expedite the Consumer Council's draft Food Act by urging the Prime Minister to include it on the legislative agenda so it can be promptly considered and elevate Thailand's food safety system to manage risks from start to finish.
For consumers, this issue should not end with advice to “be cautious” because the average person cannot visually detect cadmium, lead, or arsenic contamination in vegetables or fruits. Nor should consumers bear the burden of guessing the safety of market products. Therefore, clear and accessible test results are vital mechanisms to protect consumer rights.
Consumer protection should not begin only after harm occurs but from the beginning of the food chain with an effective surveillance system, accessible data disclosure, and laws empowering timely management of unsafe food to ensure safe food is a fundamental right for all.