Monitoring of tritium concentrations in tap water and rainwater collected in Thailand

This study aimed to measure tritium (3H) concentrations in Thailand. Nationwide tap water samples were collected in July 2021. Rainwater samples were collected monthly during May-October 2020, April-October 2021, and February-March 2022 in Chonburi province and in Chiang Mai province during July-November 2021, January 2022, and March-June 2022. The measurements of 3H activity concentrations were conducted by Osaka Sangyo University (OSU) and were compared with measurements by the Thailand Institute of Nuclear Technology (TINT). The results from OSU and TINT showed that 3H concentrations in tap water were matched in the ranged from 0.08 ± 0.03 to 0.28 ± 0.04 Bq L-1, while those in rainwater samples collected from Chonburi province and Chiang Mai province are also matched in the ranged from 0.11 ± 0.02 to 0.21 ± 0.03 Bq L-1 and 0.19 ± 0.02 to 0.57 ± 0.04 Bq L-1, respectively. Our measured result suggests that 3H concentration in tap water and rainwater shows a similar relation depending on latitude.