Marlyss Simmons sent me a story on the development of a natural insect repellent with real teeth. NPR carried the story --- you know, the NPR whose funding is being threatened.
Repelling Bugs with the Essence of Grapefruit by Richard Knox describes research on nootkatone, a substance found in grapefruit and Alaskan yellow cedar trees. It has been approved as a food additive and is already used in Squirt.
Nootkatone is effective against ticks which cause 30,000 cases of Lyme disease yearly and mosquitoes which carry West Nile virus, not to mention malaria in tropical climates. It is nongreasy, pleasant smelling, and dries quickly. In a 2% solution it is long lasting.
As for its insecticide properties, it kills quickly. It affects the insect's nerve cells so "they basically vibrate them selves to death". Just imagine watching a tick quivering before it falls screaming to the ground! Further good news --- it is rapidly biodegradable and therefore not a threat to pollinators.
The CDC holds the patent on nootkatone and has contracted with two companies to begin production. The bad news is the cost. It is currently $4,000 per kilogram for food grade, but that level of purity would not be required as a repellent. There is also some hope that a similar chemical which is called nootkatol will be effective. This is currently a virtually free waste product.
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