32P measurement of urine samples and internal dose assessment for radiation workers in life science laboratories

Abstract

32P measurements of urine samples and internal dose assessments were conducted for workers in life science laboratories. A procedure for sample pre-treatment was established and validation was performed to exclude interference and to detect 32P levels accurately. The detection conditions for Cherenkov radiation were evaluated and the accuracy of Cherenkov radiation measurements validated. The analytical and measurement procedures were applied to urine samples collected from 11 workers from life sciences laboratories. The results of the measurements generally indicated very low background radiation levels, but daily urine samples from two workers were above the minimum detectable activity. The 32P concentrations for two of the workers were 29.3 ± 10.4 Bq•d−1 and 24.1 ± 11.8 Bq•d−1, respectively, at intake levels of 4.12 kBq and 2.61 kBq. The effective doses for these two workers were 4.6 μSv and 2.9 μSv. Overall, the results indicate very low levels of radioactivity, except for cases related to specific working conditions.