Agricultural office and Chiang Mai research centre tests (Dec 2025 to May 2026, six rounds) found cadmium, lead and arsenic above standards in at least 21 crops grown along the Mae Kok river in Mae Ai, including chili, corn, cucumber, garlic, pineapple, eggplant, mango and long bean. Cadmium exceeded limits in every round. The source is not yet confirmed; flooding-borne sediment and the river are suspected. The Consumer Council says results took 8 months to reach the public and no recall or area-control measures are yet set. If you buy produce or raw materials from Mae Ai or nearby riverside plots, ask suppliers for origin and test records, and hold any lots you cannot trace. Possible future rules: area controls on planting, and faster post-market recalls under the Food Act.