A new study led by researchers from the National Research Centre on Human Evolution (CENIEH), Spain), and resulting from an international collaboration with the University of Oxford, UK, just showed for the first time a correlation between the use of computerized microtomography (also known as mCT) and the reduction of the amount of collagen preserved in modern and fossil bones and teeth.

In other words, while the use of this technique do not directly impact radiocarbon dating results, it nevertheless tends to favour the degradation of proteins in bones, producing irreversible damages and potentially limiting, or precluding, future analytical studies on these remains.

“Over the last decades, mCT has becomes a very popular technique in our field of research, as it allows creating a virtual copy of highly valuable fossil remains”, says Palaeoanthropologist Dr Laura Martín-Francés, recipient of a European Marie Skłodowska-Curie Fellowship and co-author of the work. “Thanks to this technique, it is possible to access the inner structure of fossil specimens, and build high-resolution 3D reconstructions without causing any visible damage”, adds the CENIEH researcher.
For this reason, the technique has been widely regarded as being non-destructive and is being routinely used within the scientific community. However, mCT employs highly energetic ionizing radiations, called X-rays, which are known to induce changes, at microscopic level, in the material they interact with. Importantly, these changes are irreversible, and cumulative.

“It is therefore no surprise that mCT may favour the degradation of proteins in bones and teeth, but this had never been experimentally confirmed” says Dr Mathieu Duval, also researcher at CENIEH and leading the study. “Given these results, we simply want to recommend caution regarding the systematic and unlimited use of X-ray mCT scanning in palaeoanthropology, or in other related disciplines involving fossil material” concludes both researchers.

This investigation has received financial support from the Spanish State Research Agency (AEI) through a Ramón y Cajal Fellowship RYC2018-025221-I funded by MCIN/AEI/ 10.13039/501100011033 and by “ESF Investing in your future”, and from the Horizon Program-Marie Sklodowska-Curie Actions of the EU Ninth programme (2021–2027) under the HORIZON-MSCA-2021-PF-01-Project: 101060482.

More information
Duval, M., Martín-Francés, L. (2025). Scientists could be accidentally damaging fossils with a method we thought was safe. The Conversation Australia, 16 July 2025. https://theconversation.com/scientists-could-be-accidentally-damaging-fossils-with-a-method-we-thought-was-safe-258827.