The discovery of cadmium contamination to rice and soil in Thailand began in 1998 (1,2). Dr. Robert W. Simmons, a senior researcher at International Water Management Institute (IWMI) and his team decided to conduct a study in Mae Sot district, Tak province, Thailand. Based on their experiences from water and soil contamination studies in China and other Asian countries, they foresaw that rice growing in the vicinity of zinc mine could lead to cadmium, which co-exists naturally with zinc, contamination to rice and would inevitably cause adverse health effect, particularly itai-itai disease, or chronic cadmium poisoning, among the exposed population. IWMI jointly quantified soil and rice cadmium contamination in Mae Sot district with Dr.Pichit Pongsakul, a soil and plant expert at Department of Agriculture, Ministry of Agriculture, Thailand. From 1998 – 2000, the first phase of the study was done in the most potentially polluted area where water was naturally supplied by Mae Tao Creek in which sediment was suspected of having high contamination of cadmium.