I've included this article because although it doesn't mention Egypt, it deals with a subject that is of concern to many archaeologists looking at the rock art of Egypt, including that of the Eastern Desert. This article highlights some of the man-made problems facing those wishing to conserve the art, including graffiti and the actual physical removal of some pieces: "Unlike the rock art buried deep in caves in southern Europe, African art was painted and etched on rock faces far more exposed to the elements - and the public. Looting of the treasures also seems more commonplace".
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