The Existence and Removal of Evaporable 137Cs-Containing Compound(S) From the Extract of Lichen Cetraria Islandica

The aim of the work described here was to investigate the existence of evaporable ¹³⁷Cscontaining compound(s) in lichen and to suggest a possible way of dealing with a phenomenon during lichen exploitation. A sample of lichen, Cetraria islandica, was submitted to aqueous extraction and the extract was monitored to be ¹³⁷Cs-radioactive. It was heated according to the experimental schedule and the resulting vapour passed over a layer of activated charcoal. By measuring the decrease in the radioactivity content of the lichen extract after heating and the radioactivity of the adsorbent it was found that a significant amount of the extracted ¹³⁷Cs could be evaporated and bound to the charcoal adsorbent (40.6%). If not captured, this radiocaesium may lead to air pollution, especially of immediate breathing space.