Fluoride in the bones of foxes (Vulpes vulpes Linneaus, 1758) and raccoon dogs (Nyctereutes procyonoides Gray, 1834) from North-Western Poland.

Assessment of exposure to fluoride (F(-)) is increasingly focused on mineralized tissues, mainly bones. Their periodic growth and continuous reconstruction make them a good material for studying long-term F(-) accumulation. In this study, F(-)concentrations were determined in the bones of foxes and raccoon dogs from north-western Poland and relationships between bone F(-) and the age categories of the animals were attempted to be identified. Bone samples were collected from femurs of 32 foxes (15 males and 17 females) and 18 raccoon dogs (10 males and 8 females) from polluted, medium-polluted, and unpolluted by F(-) areas. Bone F(-) was determined by potentiometric method, and results were expressed per dry weight (dw); they ranged from 176 to 3,668 mg/kg dw in foxes and from 84 to 1,190 mg/kg dw in raccoon dogs. Foxes from north-western Poland accumulated much more F(-) in their bones than raccoon dogs. Our study shows that the assessment of hazards created by industrial emitters can be conducted conveniently by the measurements of fluorine content in hard tissues of wild animals. Due to availability of such type of material for studies, it seems that the analysis of fluoride content in bones can be a good tool in the development of ecotoxicology.