Teeth of the red fox Vulpes vulpes (L., 1758) as a bioindicator in studies on fluoride pollution

An examination was made of fluoride content in the mandibular first molars of the permanent teeth of the red fox Vulpes vulpes living in north-west (NW) Poland. The teeth were first dried to a constant weight at 105°C and then ashed. Fluorides were determined potentiometrically, and their concentrations were expressed in dry weight (DW) and ash. The results were used to perform an indirect estimation of fluoride pollution in the examined region of Poland. The collected specimens (n = 35) were classified into one of the three age categories: immature (im, 6–12 months), subadult (subad, from 12 to 20 months) and adult (ad, >20 months). The mean concentrations (geometric mean) of fluoride were similar in the im and subad groups (230 and 296 mg/kg DW and 297 and 385 mg/kg ash, respectively), and significantly smaller than in the ad group (504 and 654 mg/kg, respectively, in DW and ash). Basing on other reports that the ∼400 mg/kg DW concentration of fluoride in bones in the long-lived wild mammals generally reflects the geochemical background, it was found that 57% of the foxes in NW Poland exceeded this value by 9% to 170%. This indirectly reflects a moderate fluoride contamination in the tested region

Characterisation of health status parameters in roe deer from highly polluted areas (cadmium, lead, orsanochlorines) compared with areas of low pollution

The objective of this study was to examine whether a high heavy metal contamination (Cd, Pb) as well as a high contamination with organochlorine compounds (PCB) in selected individuals induces changes in specified health status parameters (immune status, exposure to different viruses) in freeliving deer. Therefore, extremely polluted regions (Bitterfeld (B) and Harz (H) ) were compared with regions of very low pollution levels (Mecklenburg-Vorpommern (MVP) and Schleswig-Holstein (SH)). Free-living species with small home ranges such as roe deer are particularly suitable bio-indicators. Their residue concentration reflect the local contamination of their food and water supply, as well as the range of accumulation of persistent contaminants within the food chain. Overall a positive association between polluted regions and an above average cadmium level could be detected in all age groups. Regarding lead contamination significant differences were only found between roe deer in the Harz compared to roe deer in SH, MVP, and B. Only low concentrations of organochlorine compounds were detected. Regional differences were present regarding unspecific irnmunological parameters. Nevertheless, these differences were independent of Cd contamination. Furthermore, this study show that the specific immune response against different viral agents is probably not influenced by an increased contamination with Cd. This is consistent with previous studies describe in the literature. In conclusion, Cd contaminated roe deer have not been found to have a reduced health condition considering the afore mentioned parameters. A possible explanation could be that the life span of roe deer is usually too short for heavy metal contamination to induce a distinct chronic effect on these health status parameters. © 2001, Blackwell Wissenschafts-Verlag