US Coins

Hazardous to your health

Last month I began a two-part series discussing the safe handling of exotic numismatic materials.

You will remember that many of these materials — wood, feathers, skin and hair — are susceptible to insect damage. As such, it is highly probable that these objects were treated with some sort of toxic insecticide prior to coming in to your collection.

If you have this material in your collection, it is important that you be aware of the risk and take steps to protect yourself and your family. I speak of this from a personal experience. Many years ago I treated, in a museum, a feather object that was contaminated with arsenic. Initially, I had no idea that it had been treated with an insecticide. It was not labeled as such and the documentation that accompanied it made no mention of it either. I only discovered this after having it tested.

I now err on the side of caution when handling objects that I suspect could have been treated with toxic chemicals in the past.

Heath concerns

Health concerns are associated with exposure to insecticides. The toxins can be inhaled as dust and absorbed through the skin. For those wishing to read more about the toxicity of common insecticides and fumigants, please refer to the Canadian Conservation Institute’s Technical Bulletin No. 15, Solving Museum Insect Problems: Chemical Control (

Safe handling

I use the following guidelines for the safe handling of collections that may have been contaminated with toxic insecticides. They have been adapted from a set of guidelines prepared for the Society for the Preservation of Natural History Collections by Monona Rossol, industrial hygienist with Arts, Crafts and Theater Safety, and Jane Sirois, Conservation Scientist, Canadian Conservation Institute:

? Wear disposable nitrile gloves when handling material — cotton gloves will not protect you from toxins.

? When removing gloves, be careful that your hands do not touch the exterior surface of the gloves.

? When finished handling your collection, discard gloves and wash hands with soap and water before handling other objects or eating or smoking.

? Do not eat, drink or smoke when handling these collections.

? Wear a protective lab coat or clothing when handling collections to keep dust off your clothing — remove your protective clothing when you are finished.

? Wear a dust particle mask or respirator fitted with a high efficiency particulate air (HEPA) filter.

? Set up a separate work area away from areas where food is eaten or prepared.

? If possible, work with good ventilation.

? Wash protective clothing separately from other clothing.

? Regularly wipe down your work surface with soap and water.

? If you clean up with a vacuum cleaner, make sure it is a HEPA vacuum.

Display and storage

It is advisable to display these objects in an exhibit case. A sealed case will keep any contaminated dust from being dispersed throughout the room. A case will also keep curious hands from touching the objects. This is particularly important if children are around.

When storing these objects, it is recommended, from both a pest management standpoint and health and safety, to store them individually in resealable polyethylene bags.

There are many technical articles dealing with pesticide-contaminated museum objects. I recommend the 2005 Altamira Press book, Old Poison, New Problems: A Museum Resource for Managing Contaminated Cultural Materials, by Nancy Odegaard and Alyce Sadongei. It is an excellent primer.

Susan L. Maltby, Toronto, is a private conservation consultant, with an interest in numismatic preservation.

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