Book Mold, Foxing or Age-Tanning?

3/23/2022 (Permalink)

It can sometimes be hard to distinguish between mold on books and what is known as foxing and age-tanning because at first glance they look similar.

How should I store or pack my books to prevent mold?

If stored in a good environment, paper made in Europe from the late medieval period through to the mid-19th century tends to be in good condition. Paper made after the mid-19th century, however, may be affected by the poor quality materials from which it was made. From the mid-19th century onwards, increasing demand for reading material coincided with the development of mechanized papermaking and printing. This allowed the widespread use of cheap and plentiful wood pulp as the raw material for paper making. Wood pulp can simply be ground up and then made into paper. This type of pulp, known as groundwood, contains all the acidic components that are present in the wood. Paper made from groundwood pulp, e.g. newspaper, is cheap to produce but inherently very acidic, according to the Victoria and Albert Museum. The use of groundwood in old books can immediately be identified by the way the paper has turned a rusty-orangey-brown as the acids in it work away at the fibers, according to Rhollick.

Avoid storing books in attics, basements and garages and keep boxes slightly off the floor and away from the walls. This prevents damage from minor flooding and the airflow will help avoid insect damage and mold. For long term storage of valued books, individual, archive quality, boxes are a great option.

How often should I perform regular maintenance on my books?

Removing books from shelves once or twice a year to dust them will keep them clean and is a good way of noticing problems with mold or insects before too much damage is caused.

Besides mold, what else can cause yellow/brown/orange spots or browning on books?

1. Age tanning, or browning, occurs over time on the pages of books. This kind of deterioration is commonly seen in books printed before the advent of acid-free paper in the 1980s, according to Biblio.com. Tanning tends to start from the outer edges of books and moves inwards over time, thus creating a yellowish or brownish border on the pages. This process can show up on just the edges of pages, when this occurs it is sometimes referred to as "edge tanning." The end papers of books are usually more acidic than the rest of the pages, so they undergo tanning faster. The process is more noticeable in the areas where glue has been applied to the back or where bookplates or newspaper cutouts have been kept says freelance writer, Satabdi Mukherjee. The browning of pages in older books will continue to be both part of the charm and challenge of book collecting.
2. Foxing describes disfiguring small yellow brown spots or blotches on paper. Two main causes are mold and iron contaminants in the paper. Molds feed on the paper itself, as well as any dirt or organic material on it, for example, finger marks, food stains and squashed insects. Tiny metal impurities can be found in paper as a result of the original manufacturing process. Damp conditions will cause iron contaminants to rust. In some cases a conservator may be able to reduce the disfiguring effect of foxing, but in many cases you simply have to accept this old damage.

Is old-book smell always mold?

No. Explained best by Ann Elizabeth Wiener for the Science History Institute, that no one can deny that old books have their own distinct scent but that does not necessarily mean they have mold. Some love “old book smell’ while others despise it but everyone can agree that it is a potent, unmistakable smell but it can be a hard order to describe. That may be because no two books smell exactly the same. The complex scent is actually an amalgamation of specific chemical markers of decay that combine with how a book was made and how and where it was stored and used by the people who have touched it. In essence, when we breathe it in, we are simultaneously smelling the life and the death of a book. The paper, inks, and adhesives that make up a book contain hundreds of volatile organic compounds (VOCs). As these components break down, VOCs are released into the air, and we detect them in the form of that distinctive odor. (New books release their own, very different VOCs. Inks, solvents, adhesives, bleaching agents, and other chemicals involved in modern manufacturing processes combine to produce the crisp, synthetic smell you notice when you snap open a freshly printed text. Environmental factors, such as the kind of climate or room a book was stored in, whether it was dusty or dirty or exposed to constant sunlight or mildew, all contribute to a book’s smell profile. So to sum up, just because a book can smell like it’s past does not mean it has mold.

What may cause mold on my books?

Air carries moisture and paper is really good at absorbing water out of the air. Water rapidly escalates the deterioration of paper so humidity is extremely harmful to your books. Try to keep your books in a controlled humidity situation, according to BookWritten.com. Mold growth is caused by high relative humidity or dampness, combined with poor air circulation. Relative humidity measures the amount of moisture that is in the air relative to the maximum amount of moisture that the air could hold at that temperature. If conditions become dryer and relative humidity drops, the mold should become dormant, but will reactivate again if relative humidity rises. If you have mold on books, try to locate the source of the dampness and address the underlying cause of your problem.

What to do if you find mold in your books in your Toms River home, study, office or library?

SERVPRO of Toms River specializes in mold remediation, the cornerstone of our business. We have the training and expertise to safely handle any mold situation. Call us today at 732-349-9898 today for your mold damage emergency.