RESUMO
The Human Monitoring Laboratory, which acts as the Canadian National Calibration Reference Center for In Vivo monitoring, has constructed a robust neck-thyroid phantom for use in the Canadian Thyroid Intercomparison Program. The phantom is rugged and capable of being distributed through the mail with no expectation of a leak of radioactive materials; it is anthropomorphic; the thyroid inserts simulate 125I and 131I; the phantom can be used to mimic different layers of adipose tissue over the thyroid insert; and it is cost effective. This paper describes the design criteria and the manufacturing process; the performance characteristics have been described in an earlier publication.
Assuntos
Pescoço , Imagens de Fantasmas , Monitoramento de Radiação/instrumentação , Glândula Tireoide , Canadá , Humanos , Radioisótopos do Iodo/análise , Serviços PostaisRESUMO
The body burdens of 137Cs were measured in 74 children from Belarus who had been exposed to fallout from the Chernobyl accident. The children were between the ages of 8 and 12 y old and were visiting the Ottawa area during the summers of 1991 and 1992. The body burdens varied from 0.04-2.25 kBq, which are less than or comparable to the amount of natural 40K in the children's bodies. There was no apparent dependence on age or sex. The body burdens were related, to some extent, with recorded fallout levels in the region of origin but did not appear to change significantly from 1991 to 1992. During their stay in Canada, radiocesium was being cleared from the children's bodies with a mean half-time of 33 d (range = 12-77 d). The highest intake rate of 137Cs was estimated to be 18 Bq d-1 and the highest dose rate was 0.13 mSv y-1.
