Over time, acetic acid is produced in acetate film by a catalytic degradation process that causes the film to give off a vinegar odor, which is referred to as vinegar syndrome. The odor is a sign that decay has begun; during the remaining life of the film, the rate of decay will increase. This degradation is prompted by poor storage conditions, and leads to eventual delamination and decomposition of the film, rendering it unusable.

In fall of 2019, select microfilm in MAIN, Special Collections, and LINX were tested for acetic acid. Based on the test results, it was recommended to rehouse certain reels of microfilm in new boxes, to remove some from the collection, and to clean or remove certain storage shelves/cabinets. This project is ongoing, and Circulation, Special Collections, and LINX staff are collaborating with Preservation to create the best possible environment for the film. Project goals are to determine the state of microfilm held in the Libraries, and to provide storage-related recommendations to slow down the rate of decay.

If you have questions about microfilm rehousing or note a vinegar odor where microfilm is stored, contact us.