Cracked microfilm

In a change from our typical themes, we present a mystery: The Case of the Salt and Vinegar Microfilm. A frightening tale of degradation, fitting for Halloween this weekend. The piece is a work of fiction very loosely based on true events from Mullins Library.


Oh, that smell…

Sounds of a typewriter clicking and the steady thumping of rain hitting the pane of a window

I was minding my own business, getting a lay of the land as it were, when I stopped abruptly. It was a smell: a distinctive smell, one I’d smelled before, but not for a long time. As I turned, the view of hundreds of reels 35mm film overtook me: Bingo. I opened the drawers, one by one. All the same. That putrid, acidic smell was all too reel… I mean, real. Who, or what, could be the culprit? Thus began The Case of the Salt and Vinegar Microfilm.

black and white close up of a typewriter

Testing for clues

With thousands of reels and no time to waste, I called in my best covert assistant: A.D. Strips. Even I didn’t know what A.D. stood for, but I knew I could trust him with this special task. He worked fast, like lightning fast, usually getting me the information within 24 hours and without any invasive or compromising repercussions. He chose a handful of subjects, hoping to get the most information out of the fewest in effort to be discrete – and it worked! We could see clearly the condition that plagued these poor reels: Acetic Acid Syndrome. I know what you’re thinking, acetic acid, that sounds terminal. It can be, but fear not my dear reader, I wasn’t going to let anything like that happen. There might still be time before the inherent chemicals broke the films down into dry, cracked, and useless pieces of plastic: all information within them lost to time.

A-D Strips used for determining pH with the spectrum of colors
A-D Strips (Evidence for acid levels in film via pH indicators)

A.D.’s work gave us a barometer of sorts. It helped us locate the concentrations of infection. Even though he couldn’t speak, his color-coded system gave me all I needed: The range was a bold blue to a sickly yellow with all the spectrum of green in between. As I held the proof, I breathed a sigh of relief. Thankfully much of the collection was in the blue-green range meaning it wasn’t past the auto-catalytic point, but still inconsistent across the board. Our reels were sick, but not in need of intensive care. Even so, I knew the next steps would be tricky. There had to be another factor impacting the infection, I just couldn’t put my finger on it.

Black and white photo of a man standing under a lamppost at night with a partial lit sidewalk
Our Contemplative Detective

An Unfriendly Acquaintance

I was ruminating when a knock came at the door. A tall, dark-haired specimen strolled in wearing a wool coat riddled with moth holes and smoking a cigarette on the end of a yellowed Bakelite holder. “What do you want, Enivra?” I asked, looking back at my notes. I wasn’t surprised she’d come around. Envira Mentl Condishuns was a frequent troublemaker this side of town. Though many cases seemed to be connected to her, I could never tie anything explicitly to her handiwork – it was all circumstantial. “I’m surprised you haven’t come knocking on my door yet,” she said in a sickeningly sweet tone, leaning in closer to me. She stood there just waiting for me to respond. “Alright,” I said as I leaned back in my chair, “I’ll bite. What makes you think I’m even considering you in this case?”

Black and white image of a woman's face blurred by a wet window pane
Envira – the mysterious femme fatale

She laughed with a lack of control, a cackle if I ever heard one. “Because I impact everything! The air density, the moisture content, the temperature, the pollutants, even the microclimates! I’ve got them all wrapped around my little finger. I can put a stop to all this – for the right price.” She winked and knocked some ash on to my desk. That’s all this ever was to Envira: money. You’d think she’d be able to afford a better coat since she was always so cold, but maybe she liked the moths that seemed to dance around her, giving emphasis to her every word. “This doesn’t concern you, Envira. I have a different suspect in my sights. Thanks for stopping by though.” I got up to lead her to the door like the dozens of times before. She shivered and her expression changed, “But, really? Who? What is it? If it’s the pests, I can work my magic with them too.” She looked almost desperate to be involved. When she grabbed the sleeve of my jacket, I knew she was, and I hated to see her like this. Then it hit me. It was something she had mentioned so quickly, I could have missed it. Maybe she was part of this case after all. “Envira,” I said, quickly turning to meet her dark, shadowy eyes. “I have an idea and I believe you are wrapped up in all this, but you have to give me some time to figure this all out.” She seemed satisfied with this answer and promptly left, and with a flutter of moths and smoke trailing.

Environmental conditions graph
Temperature and Humidity Fluctuations (More Evidence)

The Solution presents Itself

I got on the rotary phone as soon as Envira left. With each passing day, the reels were getting more and more infected: an exponential change that couldn’t be reversed, but I realized it could be managed! She had given me the idea even if she didn’t know she had. While the reels were comprised of a cocktail of chemicals themselves, it was also their storage conditions that controlled the infection! The acidic paper boxes, air-tight metal cabinets, paired with fluctuations in humidity and temperature created microclimates which enabled the off-gassing chemicals to accumulate within a contained space, spreading the condition to other reels in the same cabinet. This explained why the condition was magnified in specific areas but not in others. While the infection itself was caused by the reels’ chemical makeup, the spread and intensity of the infection was being caused by the storage, so if we changed the storage condition of the reels, it might stave off the potential for new or worsening infection! Jackpot!

Hollinger microfilm boxes
Examples of Microfilm Boxes from Hollinger

And that brings us to today, my dear reader. It’s a long road ahead replacing the old paper boxes for newer, acid-free paper boxes, and cleaning out or replacing the metal cabinets. Ideally, cold storage like refrigerators or freezers, will come into play to completely halt the spread, dead in its tracks. With thousands of reels to rescue, it might seem like the case will never close completely. However, with diligent monitoring of the environmental conditions and the updated storage conditions, these reels are definitely on their way to stability. Once Acetic Acid Syndrome rears its ugly head, it’s here to stay, but that doesn’t mean we can’t manage it and protect the information we hold dear. And with that, I closed The Case of the Salt and Vinegar Microfilm.

As the door closes, we see the detective sitting, feet up on his desk, staring out the window, expectant of the next case.


We hope you enjoyed this kitschy diversion from the norm, but we also want to stress the hints of truth in the narrative: environmental conditions like humidity, temperature, storage materials, and lack of attention to particularly susceptible materials can lead to disastrous consequences. Monitoring and mitigation are two aspects of preservation at work to ensure the longevity and usability of collections materials. Currently the Preservation Unit is working with multiple departments to mitigate the impact of Acetic Acid Syndrome in our microfilm collections through updating storage conditions and further monitoring, among other creative solutions. If you smell salt and vinegar in a library, we hope it’s just a rogue bag of chips and not the microfilm!