The in‐situ Sr isotope determination of low‐Sr bioapatites is challenging and requires monitoring several interferences, among others, Ar‐CaPO. In particular, the analysis of human bones and teeth has revealed several pitfalls, which affect the ability to obtain accurate results. In this commentary, I review the data from the paper of Meijer et al. (2019), trying to address some accuracy issues arising, in my opinion, from polyatomic interferences. After a tentative calibration of their data, using the 1/88Sr signal (V−1) as a proxy of the Sr content, the enamel specimens (enamel Ar‐CaPO corrected 87Sr/86Sr ratio = 0.7078 ± 0.0032; mean ± 2σ) are closer to the likely local bioavailable Sr (bone Ar‐CaPO corrected 87Sr/86Sr ratio = 0.7071 ± 0.0011; mean ± 2σ).