The epiphytic lichen Parmelia caperata was used systematically as a bi
oaccumulator of radionuclides in the Travale-radicondoli geothermal he
ld (central Italy). The results showed that radioactivity in this area
is not different from that of other non-geothermal areas and that the
exploitation of geothermal resources should not cause an enrichment i
n radioactivity. However, the survey also revealed a negative associat
ion between total beta radioactivity in lichens and the distance from
geothermal power plants, so that the latter may represent a source of
local radionuclide pollution. (C) 1997 CNR. Published by Elsevier Scie
nce Ltd.