The role of post-mortem alteration in tooth enamel revisited: A combined strontium isotope and geochemical evaluation

Assessing post-mortem alteration of tooth enamel in archaeological burial sites of interest is critical and required in order to accurately interpret the isotope composition of bioavailable Sr for use in determining migration patterns of populations in ancient civilizations. Several statistical approaches have been established to evaluate the degree of post-mortem alteration within tooth enamel, and these are based on the incorporation of trace elements (Mn, V, Fe, REEs, Th, U) typically present within the burial environment. In this study, both new and previously reported chemical data and radiogenic Sr isotope ratios for both modern-day and archaeological tooth enamel samples are presented, which range from pristine to altered in nature. Significant correlations between elevated abundances of mobile elements (V, Fe, Nd, U) and their corresponding Sr isotope signatures are limited and are most prevalent when the latter are compared to their Fe contents. Tooth enamel samples affected by diagenesis based on their outlier chemical composition do not necessarily record perturbed Sr isotope signatures, and therefore should not be precluded precipitously from provenance studies.