Technique Sniffs Out Mold In Film Archives

Like humans, fungi have a taste for old movies. Unfortunately, the microbes prefer to eat than watch the cellulose acetate film. This moldy predilection destroys valuable film in archives and poses safety concerns to conservators who are exposed to the fungal spores. Now researchers have developed a technique to detect the odor profile of fungi that have digested a meal of film (Anal. Methods, DOI: 10.1039/c2ay05826j).

The project started when the U.K.’s North West Film Archive approached a team led by Craig E. Banks and Gavin Bingley at Manchester Metropolitan University for help in distinguishing between mold and plain old dust on film.

The archive often receives donations of valuable film that has been stored in less-than-ideal locations, such as attics or basements, Banks says. Conservators often have to diagnose a potential fungal film infection by trying to grow the mold in a lab, which is time consuming and can pose a health hazard.

The new technique employs gas chromatography/mass spectrometry to detect molecules that float off mold communities after a hearty movie dinner. To find telltale compounds of a fungal infection, the team first cultured 17 kinds of fungi often found on contaminated film and collected the volatile molecules wafting off the cultures. They spotted more than 150 airborne molecules, but narrowed that number down to three key chemical markers of problematic mold metabolism: 1-octen-3-ol, 3-octanone, and 3-octanol.

One of the benefits of the technique, Bank says, is that it can detect mold metabolism before the fungal growth is easily seen by eye. He thinks the technique could provide an early warning for film archives.