Mold and mildew are generic terms that refer to various types of fungi, microorganisms that depend on other organisms for sustenance. Mold propagates by disseminating large numbers of airborne spores which travel to new desirable locations to germinate. Molds excrete enzymes that allow them to digest organic materials such as paper and book bindings, altering and weakening those materials. In addition, may contain colored substances that can stain paper, cloth, or leather.
Remember mold can be dangerous and can pose a major health hazard. Exposure to mold can lead to debilitating allergy even among people not prone to allergies. Toxigenic molds, like the common ‘black mold’, produce mycotoxins which are toxic to the cells of higher plants and animals, including humans.
The most important factor in mold growth is the presence of moisture, the higher the relative humidity the faster the mold will grow. Mold spores, active or dormant, are everywhere on everything, it is not possible to create an atmosphere free of spores. The only way to control their growth is to control their humidity and temperature and prevent the addition of new active mold.
rule of thumb #2 – The ideal temperature for storing books and documents is between 60-64° f (16 – 18° c) and 45% – 55% relative humidity (RH). Which means a dehumidifier in the summer and perhaps a humidifier in the winter. Keep the storage area in this general ballpark and you shouldn’t promote mold and mildew growth.
rule of thumb #3 – IF on the outside chance you find mold or mildew on a page or a book and if you insist on trying to salvage the item, wear a face mask, and latex gloves. Bracket the page with wax paper or plastic and apply 95% pure alcohol with a soft cloth. Leave book under weight overnight. If you can see no active mold but the cover still smells mildewy, wipe the exterior with cloths laced with disinfectant such as Lysol®. Repeat if necessary and keep the item dry and segregated. Do not replace the item in the collection until you are certain the mold and mildew haven’t resurfaced.