This is a follow up to this post where I noted my horror at finding mould patches in some of my books!
After doing a bit of online research, I found a couple of useful articles.
Most of the information below has been gleaned from this article on the Biblio.com website and from this blog post on Thatcher Wine’s website.
There are plenty of other articles out there but they tend to repeat the same information.
Health and Safety for Humans and Books!
Firstly, book mould isn’t that great for humans either! If you’ve found a particularly bad outbreak in your book collection, wear a face mask when cleaning it up.
If your prized collection is very damaged and/or is very valuable, do contact a professional book conservator. You don’t want to damage your rare and expensive books further!
Mould and Mildew
Both mould (or mold if you’re outside of the UK) and mildew are types of fungus.
Evidence of mould might be spots and stains, white filaments and fuzzy growth.
Mildew takes the form of powdery flakes or a patch of spots, usually white. By the way, that nice ‘bookish’ smell you might associate with book collections and old libraries – that’s actually evidence of mildew!
If your books have suffered water damage in the past they are very likely to develop mould. I’m here with all the good news!
So far I haven’t found any direct water damage but plenty of spots and stains. Only one book had mildew judging by the colour. (Why this one book, I’m not sure! The others either side were fine!).
The mould staining also seems to be restricted to the covers or dust jackets. So far at least.
How, What, When?
Fortunately none of my books have suffered from a disaster such as flooding (the Biblio.com article mentioned at the start has advice on dealing with wet books). So the books are all dry. But how have they gotten mouldy?
Well, I live in a mild but very humid part of the world in an old stone cottage. There’s also no central heating so I should have been more proactive about preventing mould from taking hold, but there we go!
Choose Carefully!
Firstly, you can try gently brushing or wiping away any growth using a soft brush or cloth. Now, most of the mould I’ve come across in my books has been comprised of small dark spots and stains. So there wasn’t much to brush away, but you know, it’s always good to keep the books dusted!
To clean the stains, I found a few recommendations starting with gently wiping with methylated spirits.
Methylated spirits is the UK name for denatured alcohol – ethanol suited for cleaning purposes but made smelly and poisonous so you’re not tempted to drink it. The stuff you get in the UK certainly stinks!
I have used methylated spirits in the past and found it to be pretty horrible stuff to work with. So when testing it on an old cookery book, I really needed it to have a night and day effect on a stain to feel like it was worth it. I didn’t feel it did so there was no way I was going to risk it on more expensive books.
If you do use methylated spirits, make sure you are in a very well ventilated room.
Generally speaking, the key seems to be to use some kind of cleaning fluid that not only kills the mould but also dries quickly so as to limit any damage to the books. You don’t want to make matters worse by making the cover or pages soggy!
So with methylated spirits crossed off, I then tried some anti-bacterial wet wipes. They seemed to clean just as well and dried very quickly. Most importantly, they didn’t stink!
Wet wipes aren’t exactly environmentally friendly so if you do use them, don’t flush them down the loo! These days you can get biodegradable ones so those will be the ones I’ll be using going forwards.
Whether the anti-bacterial nature of the wipes works on mould, only time will tell!
Cleaning Up
Now with the choice of cleaning medium chosen, I used the following steps:
- Wipe the book or cover gently and leave to dry.
- You do need to balance killing & cleaning the mould stain and not damaging the book cover.
- There are a few book covers that I’ve opted not to wipe down at this stage as the stain or mark is very minor.
- Once dry, hopefully the book cover should look a bit better.
- I then used a protective dust jacket cover in the case of hard backs. Something like a Brodart cover is a good brand example but there are others out there.
- As a final step, I put the book in a book bag. Big omnibus books don’t fit into these but where I can, sealing the book up seems like a good idea.
Freezing the Books?
If you are feeling particularly thorough, you could try freezing your book for a couple of days. Wrap it up securely in something water proof and pop it into a kitchen freezer. It won’t magically clean up any stains but should kill any surviving mould.
Putting a book in a freezer along side frozen peas was quite a conceptual leap for me. I have tried it with one book and while I was concerned that the freezer treatment might make the pages and spine brittle, the book emerged none the worse for the experience. As expected, the stains hadn’t magically disappeared but hopefully the process has killed off any remaining mould.
One thing I did find was that taking the book out of the freezer caused condensation to immediately form on it. Not something that I wanted to happen! So as it’s currently spring time, I left the book in a sunny spot until it had warmed up enough to handle.
Storage
With the books cleaned the next step is to look at storage.
As mentioned above, I’m now going to be storing the books in protective covers and bags. So that should help keep the dust off.
Talking of dust, layers of it on top of your books can act as a medium for mould to start growing. So a regular whip around your book shelves with a duster is a good idea.
Generally speaking, advice seems to agree on keeping your book collection consistently warm but not too warm. About 21°C should be about right. Oh and just to confirm the Goldilocks nature of book storage, preferably well ventilated!
I’d also recommend getting a good reading light. It surprising what shows up under a decent light that
My home however is always going to be damp. It’s the nature of the beast where old stone cottages are concerned! Fortunately, I can move my books to my office which is still an old building but has central heating! I also work for myself so if I want to have comic books in my office, I can!
Summing Up
Let’s face it, the UK is a pretty damp part of the world! Sooner or later your books will start to show signs of age, whether that’s yellowing, dings or yes, mould. If you’re lucky enough to live in a newer build with central heating, the conditions for mould growth might be mitigated a bit. If you have any books that are rare or important to you, I’d still give them a close look and a check for any suspicious-looking stains.