Indicators of the Fukushima radioactive release in NW Romania

Abstract

As a result of the Fukushima nuclear release, 131I was found in different environmental media (rainwater, sheep and cow milk, herbage, sheep meat and thyroid tissue) in north-west Romania. On April 4, 2011 a maximum value of 1.40 ± 0.21 Bq/L in 131I activity was found in rainwater obtained from the Arad region. The obtained value corresponded with the maximum of 131I concentration in air, as measured by Toma et al. (2011) for the Piteşti area. One day later, sheep milk from the Cluj area was found to contain a maximum activity of 9.22 ± 0.95 Bq/L. A value of 0.85 ± 0.07 μSv was calculated as the total monthly effective dose received by the population as a result of the ingestion of sheep milk and sheep meat contaminated with 131I. Only rainwater samples contained 134Cs and 137Cs at levels close to minimum detectable activity. Since the determined values could be influenced by Chernobyl 137Cs, the 137Cs concentrations are subject to uncertainty. The radioiodine transfer coefficients (Fm) and the concentration ratio (CR) from herbage to sheep milk, as well as sheep meat, from the Cluj-Apahida area are also presented.