No amount of chemical cleaning of the collagen removes the dietary effect, because the dietary effect is not contamination — it is the original signal.

The only way to address it is to measure the magnitude of the reservoir effect in the relevant environment and apply a correction, or to obtain additional dates from materials that do not carry the reservoir effect — charcoal from associated fires, for example, or dates from other samples from the same individual.

None of these options is available for the Buhl burial now.

The buried bones cannot be resampled.