Radioactive waste monitored around the city hospitals in Brescia. Results of a radiometric survey and model of the radiologic impact on the environment
Albini, E.; Belletti, S.; Rossetto, E.
La Radiologia Medica 69(1-2): 37-42
1983
ISSN/ISBN: 0033-8362 PMID: 6828787 Document Number: 209195
The release into environment of liquid radioactive wastes coming from the metabolic therapy department of the Spedali Civili in Brescia was monitored during six months, with a rate of release of about 20 divided by 50 mCi of 131I every 30 divided by 40 days. Samples of 10 liters of liquid, taken from sewers downstream from the release point during a release operation, was percolated on 50 cm3 of ionic exchange resin in order to achieve a suitable counting rate with a Ge(Li) crystal spectrometer, connected to a 2048 channel analyzer. From these measurements a dilution curve along the sewers course was obtained, allowing one to know, for a given radioiodine concentration at the release point, concentration at every point downstream. In this way, by means of a simple linear compartmental model, it is possible to calculate the average individual dose taken by individuals who are living in the region (250.000 inhabitants) in one year of release operations. In our case we considered, as critical pathways to man, cow milk, meat, cereals and fruits: we obtained for thyroid, which in the case of radioiodine is the critical organ, an individual annual dose of 5,41 x 10(-4) mrem, while for total body we obtained 9,49 x 10(-7) mrem.