The structure and relative degree of mineralisation of antler and pedicle bone of yearling red deer stags
exposed either to low or high levels of environmental fluoride were determined by digital quantitative
backscattered electron (BSE) imaging. Bone fluoride content (BFC) in antlers (845±86 mg F−/kg ash,
arithmetic mean±S.E.M.) and pedicles (1448±154 mg F−/kg ash) of deer from a highly fluoride polluted area
in North Bohemia (Czech Republic) were significantly higher (P < 0.001) than those of controls from
uncontaminated regions in West Germany (antlers: 206±41, pedicles: 322±52 mg F−/kg ash). Mean
(56.5±4.5%) and maximum (84.9±2.1%) mineralised bone area of the control antlers significantly
(P < 0.05 and P < 0.001, respectively) exceeded the corresponding values for the N. Bohemian deer
(43.3±1.3 and 73.3±1.9%, respectively), while the pedicles from the 2 groups did not differ significantly. In
the pooled antler samples (n = 18), negative correlations existed between BFC and mean (rs = −0.62,
P < 0.01) as well as maximum (rs = −0.69, P < 0.01) mineralised bone area. Morphological imaging
revealed a decreased width and an increased porosity of the antler cortex in the N. Bohemian specimens.
Mean (148.5±1.7) and maximum (154.2±1.7) BSE-signal intensities (= grey levels; range between a
monobrominated (grey level 0) and a monoiodinated (grey level 255) dimethacrylate resin standard) of the
antlers from the controls were significantly higher than those of the N. Bohemian deer (140.7±2.1 and
145.7±2.2, respectively ; P < 0.05 for both comparisons). In the pooled antler samples, negative correlations
between BFC and mean (rs = −0.51, P < 0.05) as well as maximum (rs = −0.52, P < 0.05) BSE-signal
intensities were observed. No significant differences in mineralisation density parameters were found for the
2 pedicle samples, and BFC and mineralisation density of the pooled pedicles were uncorrelated.
Morphological imaging revealed bone mottling (denoting increased remodelling activity) and frequent
occurrence of apparently increased osteocyte lacunae in some of the pedicles from the N. Bohemian deer. It
is concluded that the reduced amount of mineralised bone in, and the lower mineralisation density of, the N.
Bohemian antlers resulted from a fluoride induced disturbance of bone mineralisation. The rapid growth of
antlers leads both to a high mineral demand and a high rate of fluoride uptake during antlerogenesis. This,
and the limited lifespan of antlers, which does not allow for a compensation of a delay in the onset or
progression of the mineralisation process, renders antler bone particularly susceptible to fluoride. Antlers are
therefore considered a useful model for studying fluoride effects on bone formation. Furthermore, analysis
of cast antlers enables a noninvasive monitoring of environmental pollution by fluorides.