NEW YORK, NY. August 26, 2025 — Buying used or antique books can be exciting, but it also comes with hidden risks. Many of these books may carry insects such as booklice, silverfish or even bedbugs that feed on paper, glue and fabrics. If left untreated, these pests can spread and damage entire collections. For that reason, freezing books has become one of the most reliable and chemical-free methods of protection.
A PROVEN CONSERVATION TECHNIQUE
Freezing books is not a social media trend, but a well-established practice in libraries, archives and museums. Institutions like the Smithsonian Libraries and the Library of Congress have long used freezing as part of their Integrated Pest Management programs. According to guidelines from the Canadian Conservation Institute, exposing books to temperatures of –20 °C for several days is enough to kill insects at every stage of their life cycle without harming the materials.
WHY FREEZING WORKS
Cold temperatures destroy pests by crystallizing water inside their cells, which ruptures eggs, larvae and adults alike. At the same time, freezing halts the growth of mold, which can also be a threat in books stored in humid conditions. While freezing does not eliminate mold spores completely, it keeps them dormant until the book is properly dried and preserved. Unlike chemical sprays, this process leaves no toxic residues and does not endanger readers or conservators.
FROM LIBRARIES TO EVERYDAY HOMES
The method is widely used in professional conservation, but it is also simple enough for private readers. Experts recommend placing books inside airtight plastic bags, freezing them for at least 48 hours, and then letting them thaw slowly while still sealed to avoid condensation. Some libraries, such as the University of Washington, have even reported successful treatments against bedbugs using carefully timed freeze-and-thaw cycles. This shows that the method is effective not only against paper-eating insects but also against common household pests.
SAFE, AFFORDABLE AND EFFECTIVE
Freezing secondhand books is one of the safest steps collectors and casual readers can take. It does not require expensive equipment or professional chemicals, only access to a household freezer capable of reaching low temperatures. For institutions, it is an environmentally friendly alternative to fumigation. For individuals, it provides peace of mind when bringing home books from thrift shops or flea markets.
CONCLUSION
Freezing old or secondhand books is a simple but powerful preservation tool. Backed by conservation science and widely applied in archives and libraries, it ensures that treasured volumes remain safe from insects and mold. Whether you are a collector of rare editions or just someone who enjoys hunting for bargains in secondhand stores, this method offers a practical way to protect books and keep them part of your library for years to come.
