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In salt farms of Thailand, saline ground water is pumped up and then solar-evaporated to produce salt for commercial purpose. However, when they continue to precipitate salt in the same pools, the product is stained yellow or brown in color. In order to recover only white salt, workers cut trees and create a new pool next to the old one. Due to this practice, year by year, salt-farming area loses vegetation cover and expands barren section of salt damage. In order to understand the changes of in salt grains, salt was collected and measured by PIXE. The result indicates that manganese is clearly responsible for the coloring, and possibly also irons. This information is expected to base the discussion to stop deforestation in the salt-damaged area.

National Institute of Advanced Industrial Science and Technology is working for the Global Alliance to Eliminate Lead Paint (GAELP) of the United Nations Environment Program (UNEP), under the cooperation of Iwate Medical University Cyclotron Center and Nishina Memorial Cyclotron Center of Japan Radioisotope Association. In order to demonstrate how the PIXE is useful to monitor lead in human body, hair samples were collected from local communities and analyzed by the PIXE at the University together with the control of office workers. The analysis showed a clear anomaly of lead for factory workers. It is recommended that the PIXE be added as one of the instruments to assist UNEP's lead and other heavy metal studies.

Water and tailings from lead-mining area in Kanchanaburi, Thailand were analyzed by PIXE to study how serious the alleged pollution was. Eleven water samples were collected in the field and were sealed in the tube after the pH < 2 was attained by ultrapure nitric acid. All of the samples were transported to Nishina Memorial Cyclotron Center of Japan Radioisotope Association and analyzed by its vacuum PIXE. The result showed that the water contains up to 25 ppb Pb with an average value 12 ppb. The value is lower than the environmental norm in Thailand (0.05 mg/L) but higher than that of WHO (10 μg/L = 0.01 mg/L). Tailings contain high amount of lead. Since resumption of mining is being considered to deliver the economic expectation of local people, it should be invested in treatment or containment within storage facilities. Also discharge of treated process water should be regularly monitored by competent agencies.