Leonardo da Vinci?s Codex Atlanticus, the largest collection of drawings and writings by the Renaissance master, has been infiltrated by mould, officials said recently.

The extent of any damage is not yet known to the roughly 1,120-page Codex containing his drawings and writings from 1478-1519 on topics ranging from flying machines to weapons, mathematics to botany. But officials say any conservation measures will be very expensive and there are no funds for the work.

?The mould is not spreading,? said Monsignor Marco Navoni, a historian at the Biblioteca Ambrosiana where the documents are housed. ?We need to find sponsors to come forward to help pay for analysis to establish the necessary therapy, and then do the treatment.?

The Codex is kept in a vault at the Biblioteca Ambrosiana, where temperature and humidity are constantly monitored. Mould was first identified in April 2006 by an American scholar, and confirmed by the conservation experts from the Florence-based state conservation institute, Opificio delle Pietre Dure. Until the scientific analysis is done the extent of the damage and its cause will not be identified, said the Opificio?s deputy director, Cecilia Frosinini.

?I feel a moral responsibility now that we are aware of the problem, because it belongs to the whole world, not just Italy,? Frosinini said.

Frosinini said the mould could be the result of factors including exposure during any exhibition or study, or the unintended consequence of a 1968-72 restoration.