CONCENTRATION MEASUREMENT AND EFFECTIVE DOSE ASSESSMENT IN TAP WATER OF TOURIST LOCATIONS FROM KHAO KHO, PHETCHABUN PROVINCE, THAILAND

Radon content in tap water at well-known tourist destinations in Khao Kho, Phetchabun Province, Thailand, was measured using a RAD7 radon gas detector. The average radon content in tap water from 19 samples in the Khao Kho Sub-district was 0.30 ± 0.27 Bq/L, with values ranging from 0.04 to 1.01 Bq/L. For the 20 samples collected from the Campson Sub-district, radon content ranged from 0.04 to 2.22 Bq/L, with an average of 0.56 ± 0.60 Bq/L. The health risks evaluated included the total annual effective dose (Dtotal), the annual effective dose from inhalation (Dinh) and ingestion (Ding), and the annual effective dose to specific organs, such as the lungs (Dlung) and stomach (Dstomach). The radon content in all tap water samples was below the United States Environmental Protection Agency's permissible standard of 11.1 Bq/L, and the total average annual effective dose (D), calculated from the radon content in tap water, was below the 100 µSv/y recommended by the World Health Organization’s regulatory level. Therefore, the tap water in these study areas does not pose a significant health risk based on current international guidelines.