The heavy metal content of the teeth of the bank vole (Clethrionomys glareolus) as an exposure marker of environmental pollution in Poland

Abstract

This investigation is based on the premise that heavy metals are sequestered by the mineral phase of teeth, hydroxyapatite, during their formation. Once formed these tissues are not subject to significant turnover and it is suggested, therefore, that they provide a permanent and cumulative record of heavy metal exposure during the development of the teeth. The teeth of the bank vole (Clethrionomys glareolus) were analysed by inductively coupled plasma mass spectrometry to monitor the animals' exposure to lead, cadmium, zinc, copper and strontium. Animals were trapped in clean and polluted areas in Poland in and around Krakow in 1996 and in Olkusz and Legnica in 1996 and 1997. The control area in 1996 was Bieszcady National Park and in 1997 Borecka Forest. The results showed that there were statistically different concentrations of heavy metals in the teeth of animals from different sites. The high levels of pollution from industrial emissions were related to higher concentrations of heavy metals in the teeth. Unexpectedly high levels of heavy metals in the teeth of animals from Bieszczady National Park, thought to be environmentally clean, suggested cross-border pollution from Slovakia and the Ukraine. It was concluded that the teeth of small mammals, such as the bank vole, are a sensitive and reliable marker of environmental pollution by heavy metals.