Cockroaches will not eat catnip, which is why it can be used as a nontoxic repellent against insects. Iowa State University researchers found that nepetalactone, the chemical in catnip that attracts cats, effectively repels cockroaches. In fact, nepetalactone from catnip was found to repel cockroaches 100 times better than DEET, the common commercial repellent for cockroaches, mosquitoes, and other insects.
Although scientists don't know exactly why cockroaches are repelled by the nepetalactone in catnip, this discovery could have a positive impact on pest control. Nepetalactone could be used to prevent infestations from reoccurring after an extermination, or it could serve as a preventative measure to reduce the need for more toxic chemicals.
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