Mould, musty smells and pests around trading cards
Recognise when to stop handling, isolate an affected group safely and remove the environmental cause before it spreads.
Stop routine sorting when contamination is possible
A musty smell, fuzzy or powdery growth, insect activity, droppings, webbing, staining or cards sticking together is a reason to pause. Do not continue flipping through the collection or carry open binders through other storage areas.
Mould can affect health. The US National Archives advises limiting handling, removing the source of water or high humidity and consulting a conservator for valuable or sentimental material. If contamination is extensive, follows sewage or flooding, or causes symptoms, keep away and seek appropriate professional help.
Isolate without creating another moisture trap
If items are completely dry and can be moved safely, separate the affected closed box or binder from unaffected collections. The National Archives' rehousing guidance describes wrapping dry containers suspected of contamination for isolation. Wet items need a recovery plan; sealing active moisture in plastic can worsen the situation.
Label the isolated group and record where it came from. Do not shake, brush or vacuum suspect cards in the collection room. Spores and pest material can spread to shelves, clothing and other objects.
Remove the cause, not just the visible sign
Check for leaks, condensation, damp walls, stored food, pest access, dirty shelving and boxes placed directly on the floor. Move unaffected material to a clean, dry location while the cause is investigated. A new sleeve does not correct a damp room or active infestation.
| Sign | Do not | Safer next decision |
|---|---|---|
| Musty smell, no visible growth | Spray fragrance or cleaner | Dry and inspect the room; monitor the isolated group |
| Visible mould-like growth | Brush it at the sorting table | Limit handling and contact a conservator |
| Live insects or repeated cast skins | Add household pesticide inside boxes | Isolate and seek collection-pest advice |
| Sticky sleeves or pages | Pull cards free | Stop and obtain material-specific advice |
The Canadian Conservation Institute says mouldy papers should not be treated by an untrained owner and recommends contacting a conservator. Its warning matters here because over-cleaning or the wrong technique can make damage worse.
Inspect neighbouring storage
Check adjacent shelves and boxes without opening contaminated material in the same space. Record any new sign and the environmental conditions. Once the source is corrected and affected items have professional advice, clean or replace outer storage as directed and continue monitoring.
Read when to contact a conservator for a UK route. This site does not identify mould species, recommend pesticides or provide a treatment recipe.
Sources & checks
- US National Archives: mould and insect infestation · Checked 2026-11-10
- Canadian Conservation Institute: basic care of paper documents · Checked 2026-11-10
- US National Archives: general rehousing considerations · Checked 2026-11-10