Arsenic residues in predatory birds from an area of Britain with naturallyand anthropogenically elevated arsenic levels

Birds of prey forage over large areas and so might be expected to accumulat e contaminants which are elevated but heterogeneously distributed in the ge neral environment. The aim of this study was to test the hypothesis that ar senic levels in raptors from a region with elevated environmental arsenic c oncentrations were higher than those in birds from an uncontaminated part o f Britain. Arsenic concentrations in the liver, kidney and muscle of kestre ls, Falco tinnunculus, sparrowhawks, Accipiter nisus, and barn owls, Tyto a lba, from south-west (SW) England, an area with naturally and anthropogenic ally (through mining) elevated environmental arsenic concentrations, were c ompared with those in birds from SW Scotland, where no such geochemical ano maly exists. Arsenic residues in kestrels from SW England were approximatel y three times greater than those in birds from SW Scotland for the three ti ssue types analysed. This was not the case for the other species in which a rsenic residues were similar in birds from both regions. It is suggested th at differences between species in both diet and arsenic metabolism could ex plain why kestrels have elevated arsenic tissue burdens in response to gene ral environmental contamination but sparrowhawks and barn owls do not. (C) 1999 Elsevier Science Ltd. All rights reserved.