efe-epaBy Antonio Sánchez Solís Vienna

Art restoration and archeology have become increasingly dependent on the use of nuclear technology to disinfect ancient artifacts and reveal secrets that are inaccessible to the naked eye, according to an expert.

"The advantage of these techniques is that they can be applied on a broad range of materials, the analysis can be done in a totally non-invasive way or with minimal damage to the object," Román Padilla of the International Atomic Energy Agency (IAEA) told Efe.

Padilla is an expert in various techniques including the use of X-ray fluorescence (XRF), an analytical technique that identifies the chemical composition of something.

When using this technology, one of myriad techniques that can be used in art restoration, the object is "bombarded" with high-energy X-rays or gamma rays to destabilize the structure of electrons within the object causing it to emit radiation.

What it radiates will be different depending on its chemical compound.

So the object absorbs radiation and in doing so, depending on its chemical composition, then proceeds to emit radiation back that gives scientists information about its composition.

The analysis of the results allows researchers to identify what chemical elements are present.

XRF has been instrumental in determining the exact pigments used in a painting attributed to Leonardo da Vinci.

Experts have been able to pinpoint that as well as his trademark lapis lazuli hue he used for blue pigments, other shades of blue present in his paintings were created with cobalt, an artificial pigment that was invented much later, thus confirming that a painting containing traces of cobalt would have been retouched long after Da Vinci originally painted it.

Padilla used this technique to help the Museum of Art History in Vienna identify that Indonesian "kris" daggers in its collection had traces of a mineral that would have come from a meteorite that was rich in nickel and cobalt and that struck the region where the daggers came from in the 18th century.

The Cuban expert added that another great advantage of this technology was its portability as the main instrument scientists use is a small apparatus shaped like a gun.

This is particularly useful when dealing with very delicate objects that cannot be moved from their location due to their value or size, such as frescoes or large sculptures.

Another atomic technique used in art restoration is ionizing radiation, used to disinfect and clean historical artifacts that have been damaged by parasites.

The technique started to be widely used following a successful intervention to disinfect the mummy of ancient Egyptian Pharaoh Ramses II in 1977.

Different intensities of radiation are used depending on the treatment of the object in question.

If dealing with insects, such as parasites, a lower dose is used and when treating mold higher levels of radiation are employed, Dinara Abbasova, an expert in the radiation processes, told Efe.

The reason for using different levels of radiation is because the more complex the DNA structure, the more vulnerable it is to gamma rays.

The technique consists of transferring energy to the microorganisms that are living within the object without damaging the object itself.

This specific technique was used in 2010 when neutralizing the germs that had infected a 50,000-year-old mammoth nicknamed "Khroma" that was found in thawing permafrost in Russian Siberia.

The IAEA collaborates with various laboratories of its member states in order to develop irradiation techniques further.

Thanks to these efforts in 2015, a Romanian iconostasis (a wall of religious icons often found in eastern Christianity) made of wood and from the 19th century was successfully cleared of an insect infestation.

In Brazil, the IAEA has worked closely with the Nuclear and Energy Research Institute of Sao Paolo to restore some 20,000 objects of Latin American's artistic and cultural heritage. EFE-EPA

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