Revisiting the strontium contribution of sea salt in the human diet

• Previous estimate of salt contribution to Tikal Maya strontium budget was overestimated.
• A new mixing model is described to examine the impact of salt consumption on human bone strontium isotope ratios.
• Sea salt consumption can significantly alter human strontium isotope ratios.

Sea salt is getting increasing attention as a potential source of strontium incorporated into human tissues. One particularly interesting instance was published by one of us in 2005 in which sea salt was proposed as a possible reason why the stable strontium isotope ratios of ancient Maya human tooth enamel from Tikal, Guatemala, did not match the expected local strontium isotope signature. We revisit that analysis and identify a calculation error that led to an underestimate of the amount of salt required. Our revised mixing model increases the amount of salt required by 51 percent. We consider the implications of this for the case of the ancient Maya at Tikal and also discuss application of the mixing model in other circumstances.