Q I have several old framed pictures and others in envelopes that were stored in the basement. When I opened the plastic storage box there was a lot of green powder covering the entire lot. Can they be safely cleaned for display? Also, some of this dust escaped into my living space. What is the best way to get rid of this stuff?
A Storing photographs, or any paper item, in a basement is asking for trouble. Basements typically are perfect places for breeding mold and mildew: dark, moist and cool.
It sounds like your photographs are moldy. Active mold is usually fuzzy; inactive turns powdery, as you describe. It'll stay inactive until the right conditions (temperatures generally above 60 and humidity above 70 percent), then it'll "bloom" again.
Mold almost always imparts permanent damage because the organisms are actually living off the cellulose in the paper in the photo. You won't know how badly your photos are affected until you clean them.
Because they're moldy, the Minnesota Health Department suggests wearing an N95 respirator (disposable device that covers the mouth and nose), goggles and gloves. Work outdoors if you can, or some isolated place with lots of air circulation to prevent reaction to mold if you're allergic.
Clean mold only after it's become inactive or dry. Because yours already is, use a very soft brush to gently brush the mold off the photographs if you are outdoors; use a vacuum cleaner with a HEPA filter if indoors. (Use the lowest suction power and be very careful if the photos are brittle or deteriorating.)
Sunlight kills mold, so a brief exposure to sunlight is useful. But light also fades photographs, so the emphasis is on brief. Do not exceed one hour. If the photos are highly prized, consider hiring a professional to clean them and possibly retouch them.
For the second part of your question, realize that mold spores are light and easily dispersed. They will bloom and grow wherever the temperature and humidity are right. Clean up the visible dry powdery mold with a HEPA vacuum. Remove the bag immediately outdoors and dispose of it.
