Collective dosimetry to distinguish occupational exposure to natural uranium from alimentary uranium background in bioassay measurements

Abstract

The Bayesian method presented here is well designed to derive best estimate and dose distribution for a group of workers when a contamination is difficult to discriminate from a natural background or alimentary excretion.

Circulatory disease in French nuclear fuel cycle workers chronically exposed to uranium: a nested case–control study

“…In addition, faecal and urine mass measurements were converted to radiation activity, assuming that they were conducted for monitoring of natural uranium (specific activity: 2.5×10 4  Bq/g). In our study, data on the uranium alimentary excretion patterns in a geographical region closed to the AREVA NC Pierrelatte plant20 were used to decide whether the activity measurement was representative of alimentary or occupational intakes. For urine samples, recent French data showed that alimentary intakes lead to an activity below the reporting limit (RL).…”

“…Therefore, we assumed occupational uranium intake when the urine sample was above RL. For faecal samples, we supposed occupational intakes if measured activity was equal or higher than 250 mBq20 or if the ratio of 234 U activity by the 238 U activity was greater than two, indicating an intake of enriched uranium. Faecal samples which did not satisfy these criteria were not used for the dose estimation.…”

Concerted Uranium Research in Europe (CURE): toward a collaborative project integrating dosimetry, epidemiology and radiobiology to study the effects of occupational uranium exposure

“…Uranium analytical techniques are relatively sensitive and, in some instances, the detection limit (DL) could potentially be less than excretion from normal dietary intake of uranium in certain areas (Davesne et al 2014). In order to discriminate between non-occupational, i.e.…”