Comment on Martínez-García et al. "Heavy metals in human bones in different historical epochs".

Martínez-García et al. (Sci. Tot Env. 348:51-72) have examined heavy metal exposure of humans in the Cartagena region using analysis of archaeological bones. An analysis of the lead and iron levels they report shows that they are physiologically implausible and must therefore result from diagenesis. This, and analogy with the known diagenetic origin of certain other elements, suggests that the other metal analyses they report are also unlikely to be in vivo concentrations. Lifetime heavy metal exposure cannot be deduced from diagenetically altered concentrations.