To Treat, Not Treat Art-Covering Fungi: Biocides Confer Resistance to Lascaux Cave's Microbes

Article excerpt

Biocides used in recent years to treat the growth of fungi on the prehistoric-art-festooned walls of France's Lascaux cave have eradicated some populations of human-introduced bacteria and fungi. However, some of those that remain--including some related to known human pathogens--are becoming resistant, researchers report in an upcoming issue of Naturwissenschaften.

Human presence has caused problems in Lascaux almost since the cave's discovery in 1940, says Claude Alabouvette of the University of Bourgogne in Dijon, France. Heat from lights that illuminate the art, as well as tourists' body heat, exhalations and left-behind skin cells, has changed the cave's environment drastically.

Earlier this decade, scientists found that black and white fungi had infested parts of the cave and were threatening to cover the art. Recent biocide treatments have halted the spread of fungi in most areas, but their pigments remain.

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Alabouvette and colleagues analyzed around a dozen samples from the cave. The tests confirmed that in oft-visited portions, especially those frequented by tourists before the cave was closed to the public in 1963, microbial diversity is high. …