Have you ever opened your fridge to discover something green and fuzzy inside? Or opened an old book and been hit with a strong musty odour? Chances are you have come into contact with mould.
Mould spores occur naturally outdoors and you come into contact with them every day. But in an archival setting indoors, it’s a much different story. Problems begin when the spores come into contact with collection material in an environment that nurtures their growth. Besides the physical damage that mould brings to the material, mould can also affect your health. With this in mind, there are certain precautions you need to take when handling contaminated material.
Fortunately, most of the mould that we come across in the holdings of Library and Archives Canada (LAC) is dormant. This means the spores are in a state of hibernation because the humidity level and temperature are carefully controlled. Ensuring that the environment is not favourable for mould activation and growth is one of the main factors we consider when storing collection material.
All treatment work is done in a biological containment hood after freezing the contaminated material for 48 hours at -35^(0) Celsius to ensure that the mould is inactive before cleaning. Because mould contains pigments that can cause staining, treated material often does not look any different than untreated material. For this reason, material that has been cleaned is clearly identified with a “Treated for Mould Contamination” label.
However if, during a visit at LAC, you suspect that the collection material you are handling is contaminated by mould, the rule of thumb is that it is best not to disturb mould. Therefore, you must immediately stop handling the contaminated documents! Then:
Report the problem to staff immediately; and
- Leave it to the staff who will take the appropriate actions such as segregating and sealing the material in a plastic bag to ensure that the mould does not spread.
The most important thing to remember is to protect yourself. The following is a list of protective equipment you can use when handling personal documents affected by mould:
- gloves (Nitrile™ or latex);
- mask respirators (specially designed and fitted to filter out spores);
- lab coats;
- goggles.
As long as you use common sense and take the necessary precautions when dealing with contaminated material, you should be fine, and with any luck, most of the mould you encounter will be limited to the inside of your fridge.
Questions or comments? We would love to hear from you!
Library and Archives Canada Blog 
I was recently informed that a unique historic newspaper in the LAC collection was destroyed due to mold without being copied. Why would that occur?
Thank you for your question. Library and Archives Canada (LAC) did not destroy a unique historic newspaper from its collection, as this course of action would violate the institution’s policy.
The management of LAC’s holdings is guided by a commitment that ensures that holdings are relevant and preserved in a state that the public will find useful, now and in the future.
LAC is not and will not be destroying any unique or un-copied material from its holdings. When disposition of a newspaper is considered, we first ensure that its content is available through duplicate copies or other formats such as microfilm or digital versions. Only then may we consider the disposition option.
Many publications which are more than about 40 years old were held together at the spine with animal-based glue. Insects and micro-organisms love the taste of this glue and will often have a good meal of it, to the detriment of the publication. With many places being used to store LAC items, what steps does LAC take to prevent items being destroyed in this manner ??
Thank you for your question. Library and Archives Canada (LAC) has purpose built and retrofitted buildings (such as the Gatineau Preservation Centre) where we can control the temperature and relative humidity, which assists in controlling mould growth.
Proper pest mitigation strategies are also in place and LAC has a team responsible specifically for monitoring environment controls and pest management within the storage facilities, ensuring any signs of pests are dealt with promptly.
Our facilities average a temperature of 18 – 22 degrees Celsius with the relative humidity between 40 – 50% and they are monitored at all times with the help of staff and other methods, such as wireless data loggers, which allow us to download environmental conditions anytime. If any environmental set point is breached, staff is alerted right away and an inspection will follow.
I scraped off the mould from an old photo. What should I do with the photo now? Is it salvageable? Is it safe to put the photo back in the photo album sleeves? Or should I simply scan the photo and throw it out? Thanks.
Thank you for your question. Scraping off the surface mould does not ensure that all the mould has been removed. Often, mould can be found within the material (which is very difficult to remove without damaging the object).
It would be best to segregate the photo rather than return it to the album. This will ensure that any residual spores do not contaminate the rest of the material. You may wish to scan the photograph, but ensure that the scanner is properly cleaned afterwards.
For more information, you may contact your local archives or museum to request further assistance; a qualified conservator is the only person who should be attempting treat material contaminated by mould.