The problem of black fungus threatening world-famous prehistoric paintings at the Lascaux Cave in southwestern France is "stable," a scientist said on Thursday.
France, criticised for its management of Lascaux, applied fungicide to the cave's walls in January 2008 in a bid to roll back patches of mould imperilling the legendary art.
Marc Gauthier, head of the cave's scientific committee, told journalists on the sidelines of a special Lascaux seminar on Friday, "the cave has not undergone any sharp change" since this operation.
The situation is "stable, slightly changing," he said. "The black spots are not shrinking, nor they progressing."
"The cave is sick and is currently resting," he said. "We want the patient to recover and restore its natural balance by itself."
Dubbed "the Sistine Chapel of Prehistory," Lascaux, listed as a World Heritage Site by UNESCO, includes stunning pictures of horses, extinct bulls and ibexes, painted by unknown hands some 17,000 years ago.
The cave was rediscovered by four teenagers in 1940 and became a massive draw to tourists in the 1950s and 1960s.
It has been closed to the public since 1963 to prevent deterioration of the art caused by humidity and warmth from visitors. A visitors' centre has been built outside the cave, with replicas of the painted chambers, and receives around 300,000 tourists each year.
The mould problems emerged in 2001, when a white fungus, Fusarium solani, broke out, apparently infiltrating the cave through new air-conditioning or through work to install the system.
The outbreak was tackled aggressively, including the use of fungicides and antibiotic compresses applied to the painted walls to kill mould and bacteria. Thereafter, black spots of Ulocladium fungus broke out.
The two-day Paris seminar includes specialists in cave art from South Africa, Spain, the Czech Republic, the United States and Japan, who have been invited by Culture Minister Christine Albanel to swap ideas and experiences.
The seminar's chairman, Jean Clottes, said the microscopic flora in Lascaux "is fiendishly complex."
"A hundred micro-organisms or more are cohabiting and interacting there. All it needs is for one to dominate for disaster to ensue," he said.
France's handling of Lascaux has been attacked by a vocal group of conservationists, who fault the installation of the air-conditioning system in 2001 as catastrophic and a management structure that it styles as bureaucratic and unaccountable.
(c) 2009 AFP
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