Another Use for Bounce Dryer Sheets: Repelling Gnats

For some time, many gardeners have carried around Bounce fabric softening dryer sheets to ward off insects. Entomology professor Raymond Cloyd and colleagues at Kansas State University in Manhattan and University of Illinois in Urbana, decided to test this claim about the Procter and Gamble product and discovered there’s something to it.

Cloyd’s team conducted a series of five experiments to find out if Bounce dryer sheets repel fungus gnat adults under laboratory conditions. Their tests found the average number of fungus gnat adults collected in the sample compartments containing the dryer sheets were significantly fewer, from 12 to 18 percent of the number released in the testing area. The compartments without dryer sheets, on the other hand, contained many more: 33 to 48 percent of the fungus gnats.

The researchers also tried to find out the substances in the dryer sheets that insects like gnats find repellent. The team analyzed the volatile compounds in the dryer sheets using gas chromatography–mass spectrometry. They found in Bounce a volatile compound called linalool, a colorless monoterpene alcohol used by cosmetic and perfume companies for its flower-like odor.

Linalool occurs naturally in plants such as lavender, marjoram, and basil, but has been shown to be toxic to a number of different mites and insects. The experiments also indicated high levels of the volatile compound beta-citronellol, found in plants including rose geranium, citronella, and lemon balm, and known for its ability to repel mosquitoes.

Cloyd’s findings were published online in the 1 December issue of the journal HortScience.

Photo: Damien du Toit/Flickr

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