Paper naturally expands and contracts with changes in temperature and humidity. Therefore, any extreme fluctuations can cause the paper to cockle or become wavy. The ultraviolet rays in sunlight and florescent lighting cause severe problems for paper. It will fade all art mediums and many inks. The most harmful contaminant in the atmosphere is sulphur dioxide, a gas produced by the combustion of fossil fuels.
Sulphur dioxide is absorbed by the paper and converted into sulfuric acid.
This acid causes discoloration, brittleness and eventual disintegration of the paper fibers. Most damage to paper is caused by improper handling, storage, and display methods. Poor handling causes tears and stains left from dirty, oily hands. People often attempt to repair tears with pressure sensitive tapes or glues. These adhesives migrate into the paper causing irreversible stains and are very difficult to remove.