Abstract:

Bioapatite constitutes the mineral component of bone. The stable carbon and oxygen isotopes within it carry crucial information about the lifetime activities of ancient populations, and thus this material has been widely applied in reconstructing ancient diets, tracing population migrations, and investigating individual life histories. In tropical and subtropical regions, where collagen in bone remains is generally degraded, bone bioapatite becomes the sole viable material for isotopic analysis.

As early as the 1950s, scholars engaged in radiocarbon dating had already noted that bone bioapatite contains biogenic carbon. However, due to its extreme susceptibility to diagenetic alteration during burial—which leads to contamination of its original chemical composition—the scientific application of this material has long been controversial. This controversy has also extended to the field of stable isotope research. Bioapatite crystals feature a high surface area-to-mass ratio and exhibit thermodynamic instability. During burial, they are highly prone to a series of alterations, including the adsorption of exogenous impurity minerals, ion exchange, and recrystallization; these processes can thus compromise the authenticity of their isotopic composition.

To systematically address this challenge, the international academic community has conducted multi-faceted research on the diagenetic contamination of bone bioapatite over the past three decades, yielding substantial findings. In China, however, despite the gradual publication of research cases involving the analysis of stable carbon and oxygen isotopes in bioapatite in recent years, there remains a lack of systematic reviews on the application of this material in archaeology overall. In particular, comprehensive reviews focusing on diagenetic contamination issues are still insufficient—a research gap that is especially prominent in southern China.

Owing to the hot and humid climate in southern China, collagen preservation in bone remains is generally poor, while research on bioapatite preservation is relatively underdeveloped; this has severely restricted the advancement of related paleoanthropological research in the region. To address these issues, this paper systematically reviews relevant international and domestic studies on stable isotopes in bone bioapatite. It focuses on elaborating the progress made in applying stable carbon and oxygen isotopes in bioapatite to reconstruct ancient human diets and reveal the complex behavioral patterns of ancient populations.

On this basis, the paper discusses the current research status, existing problems, and specific strategies regarding bioapatite diagenesis—encompassing its mechanisms, contamination identification, and decontamination methods. Finally, it proposes future research perspectives for the application of bone bioapatite in archaeological studies.

Key words: Bioarchaeology, bone chemistry, bioapatite, stable isotope, diagenetic contamination