Oxygen and hydrogen isotope compositions in dentine collagen correlate strongly with oxygen isotope compositions of enamel carbonate

The isotopic composition of tooth and bone has long been exploited in ecological, environmental, and archaeological studies. Increasingly, hydrogen and oxygen isotopes in collagen are used as tracers of environment and diet. However, the isotopic relationship between hydrogen and oxygen in collagen and oxygen in tooth enamel is poorly described. A new investigation of varied wild large herbivores shows that δ 18 O and δ 2 H in collagen are both strongly correlated to δ 18 O in tooth enamel carbonate (r 2 = 0.96 and r 2 = 0.86, respectively), with a δ 18 O collagen vs. δ 18 O carbonate slope ∼ 0.8 and a δ 2 H collagen vs. δ 18 O carbonate slope ∼ 6. Given that enamel carbonate δ 18 O generally reflects environmental water isotopic composition, δ 2 H and δ 18 O in collagen also reflect isotopic compositions in environmental water and may be used analogously to tooth enamel for environmental or dietary studies.