Original scientific paper
Radioactive contamination of cistern waters along the Croatian coast of the Adriatic sea
Z. Franić
; Institut za medicinska istraživanja i medicinu rada, Zagreb, Hrvatska
M. Maračić
; Institut za medicinska istraživanja i medicinu rada, Zagreb, Hrvatska
A. Bauman
; Institut za medicinska istraživanja i medicinu rada, Zagreb, Hrvatska
Abstract
Measurements of radioactive contamination of cistern waters with 90Sr, 134Cs and 137Cs have been carried out along the Croatian coast of the Adriatic Sea. An exponential define of radioactivity followed the moratorium on nuclear tests. After the nuclear accident at Chernobyl, high radioactivity levels were detected again. The pre-Chernobyl and the post-Chernobyl mean residence times of 90Sr, in cistern waters reflect the mechanism by which strontium was released to the atmosphere (atmospheric nuclear weapon tests conducted in the stratosphere or explosions in the Chernobyl nuclear reactor releasing radioactive material to the troposphere). For the pre-Chernobyl period, the mean residence time of Sr in cistern waters was similar to that calculated far fallout, being approximately 1O years. The post-Chernobyl 137Cs/90Sr activity ratio has been decreasing, but it has not yet reached the pre-Chernobyl values (=1.6). The time-dependent 134Cs/137Cs activity ratio reflects the Chernobyl reactor inventory of these radionuclides. The annual dose far the critical adult population received from 90Sr, 134Cs and 137Cs by consumption of cistern water was estimated to be a few percentages of the dose from natural background radiation.
Keywords
beta activity; caesium-134; caesium-137; gammaspectrometric analysis; radioactive fallout; radionuclides; strontium-90
Hrčak ID:
148294
URI
Publication date:
30.3.1993.
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