Predicting cadmium, lead and fluoride levels in small mammals from soil residues and by species-species extrapolation.

The effects of heavy metals on wild mammals are often assessed by analysing residues in body organs. This paper reviews published studies to determine whether cadmium (Cd), lead (Pb) and fluoride (F) residues in small mammals can be predicted directly from residues in soil or, when this is not possible, from residues in other species. It was found that residues in soil could be used to predict Cd and Pb concentrations in small mammals. There were significant (P < 0.05) relationships between Cd residues in soil and in the liver and kidneys of wood mice Apodemus sylvaticus and common shrews Sorex araneus; similar relationships occurred in field voles Microtus agrestis (0.05 < P < 0.10). There were also significant relationships between Pb residues in soil and body organs for wood mice and field voles. Insufficient data were available to relate either Pb levels in soil to those in shrews or F levels in soil to residues in any species. However, both Cd and F residues in any one of the three small mammal species examined could be predicted from the corresponding residues in the other species, there being significant relationships between species for residues in the liver and kidneys (Cd) or bone (F). Too few data were available to determine species-species relationships for Pb.