Protecting People, Property and Wildlife®

Since 1983

Do Mothballs Repel Rodents?


Many people have tried using mothballs to get rid of pesky critters like mice and rats, but the question is, does this actually work? After all, they’ve been used for about 2 centuries to keep moths away from clothing. Unfortunately, mothballs are not an effective repellent for rodents, no matter how well they’re placed.

What Mothballs Actually Do

Naphthaline, the original chemical composition of mothballs, was discovered in 1820 as a distillation of coal tar. Because of naphthaline’s flammability, mothballs now are made up of paradichlorobenzene. Generally, both of these chemicals are used in pesticides and repellents because they give off strong fumes which become toxic at high concentrations.

In order for mothballs to perform their primary job, they need to be placed in sealed-off spaces like boxes, containers, or chests. The fumes can build up in smaller places without air circulation, and they smell so bad that it keeps moths away. Thus, mothballs are chemicals which function as pest repellents when the break down into gas in contained places.

Why They Don’t Work on Rodents

Mothballs aren’t an effective rodent repellent because they were never designed to be. The key for making mothballs repellents is the space in which they are placed. If the chemicals are dispersed in a larger space, they are essentially “watered-down” and become ineffective.

So, sprinkling mothballs around a room, garage, or attic isn’t a good method for rodent control. A small number of mothballs could potentially discourage rodents from going too close to them, but it would not stop them from simply moving elsewhere in the room where the scent isn’t as strong.  In order for them to have the desired effect, you would have to put so many mothballs in a room that it would make your whole house virtually uninhabitable.

Proper Rodent Control

At Critter Control® of Sarasota, we highly recommend that you don’t use pesticides or repellents like mothballs to get rid of rodents because they simply don’t work well. By contrast, our trained technicians have years of experience dealing with nuisance rodents. They will help you get rid of any pests in your house as well as teach you how to prevent them from coming back, without using horrible-smelling mothballs. We use the most effective methods in the business, while also leading the industry with our high standards of humane animal treatment. Give us a call at 941-355-9511 for a free consultation!