“I sensed a scream passing through nature,” Norwegian artist Edvard Munch recalled in a diary entry in 1892. This event was the inspiration behind his infamous work The Scream, whose anguished figure bears the face of someone who has just been told that in the not too distant future a US president would suggest that people inject disinfectant to treat a virus responsible for a global pandemic. The figure’s expression of anxiety would probably be mirrored by Munch today too if he knew of the degradation his paintings have suffered.

To help better preserve Munch’s 1910 version of The Scream, scientists have employed an unlikely source – the world’s brightest X-ray to be precise. Using X-ray beams from the European Synchrotron in Grenoble, France, an international team of scientists probed micro-flakes from the original artwork. Coupled with non-invasive spectroscopic analysis of the painting at its home in the Munch Museum, Oslo, the team concluded that moisture was the predominant preservation problem for the masterpiece.

“The synchrotron micro-analyses allowed us to pinpoint the main reason that made the painting decline, which is moisture,” Letizia Monico of the National Research Council (CNR) Italy, and one of the corresponding authors of the study published in Science Advances, said in a statement. “We also found that the impact of light in the paint is minor.”

The painting hasn’t had an easy life. Back in 2004, two armed robbers stole the 1910 artwork, along with another of Munch’s paintings, Madonna, from the Munch Museum. Although some underworld sources pronounced that the paintings had been burned up, they were eventually recovered two years later, with the damages described as “not irreparable”. But the man-handling left its mark in the form of moisture damage on The Scream’s lower left corner.

Aside from this degradation, the development of new “screaming colors” by Munch has proved tricky to preserve. In particular, the yellow cadmium-sulfide-based pigment used across the sunset and in the neck area of the central figure has turned an off-white color. The yellow paint in the lake is flaking off as well.

Due to these factors, the painting has seldom been on display since its return almost 15 years ago. Instead, it has been kept in a protected storage area at the museum under controlled conditions of lighting, temperature (about 18°C) and relative humidity (RH) of about 50 percent. But the latest experiments on the problematic cadmium pigments, originating from the 1910 painting and from artificially aged mock-ups, suggests that a different figure of humidity would offer greater protection.

“The right formula to preserve and display the main version of The Scream on a permanent basis should include the mitigation of the degradation of the cadmium yellow pigment by minimizing the exposure of the painting to excessively high moisture levels (trying to reach 45 percent RH or lower), while keeping the lighting at standard values foreseen for lightfast painting materials,” Irina C. A. Sandu, conservation scientist at the Munch Museum explained in a statement. “The results of this study provide new knowledge, which may lead to practical adjustments to the Museum's conservation strategy.”

Not only could the team’s findings help bring The Scream back into the limelight, but it could also help to preserve pieces by Henri Matisse and Vincent van Gogh, whose work contains the same cadmium pigments.

“This kind of work shows that art and science are intrinsically linked and that science can help preserve pieces of art so that the world can continue admiring them for years to come,” Costanza Miliani, another corresponding author of the paper from of the National Research Council (CNR) Italy, concluded.