Assessment of 226Ra age-dependent dose from water intake

The radioactivity in canal and ground waters collected in a 2-year long observation from the vicinity of the Rare Earth Research and Development Center (RRDC), Phathumthani Province, Thailand, was measured in order to determine the concentration of 226Ra and to estimate the age-dependent effective dose to humans due to consumption. 226Ra activities in both canal and ground waters were well below the WHO guidance level for drinking water quality of 1 Bq L−1. The highest 226Ra effective doses per year were found for infants and teens. However, the observed levels of calculated 226Ra effective doses for all age groups in both canal and ground waters show satisfactory low values (less than 15 μSv yr−1). These values are acceptable in accordance with the WHO recommended reference dose level of 100 μSv yr−1 from water intake of 2 L day−1.