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Adding a new weapon to the fight against insect-borne illnesses including Lyme disease and malaria, the Environmental Protection Agency approved a chemical that both repels and kills ticks and mosquitoes.

The chemical, nootkatone, an oil found in cedar trees and grapefruits, is so safe that it is used by the food and perfume industries. Nootkatone is considered nontoxic to humans and other mammals, birds, fish and bees, the EPA said.

Diseases caused by the bites of ticks, mosquitoes and fleas have tripled in the U.S. in the past 15 years, the Centers for Disease Control and Prevention said in a 2018 report. They include Lyme disease, anaplasmosis and Rocky Mountain spotted fever from ticks; West Nile, dengue, Zika and chikungunya from mosquitoes; and plague from fleas.

Manuel F. Lluberas, a public health entomologist who has worked on mosquito-control campaigns around the world, said that he hoped that nootkatone would be accepted by people who fear synthetic repellents and that it could be made cheaply enough to be bought by foreign aid programs like the President’s Malaria Initiative.

The EPA registration applies only to nootkatone as an active ingredient. Any formulations using it in the future will have to be tested and registered separately. The chemical repels mosquitoes, ticks, bedbugs and fleas — and, in high concentrations, kills them, the CDC said. It may also be effective against lice, sandflies, midges and other pests, some of which can carry lethal diseases.

It is not oily, lasts for hours and has a pleasant, grapefruitlike scent, said Ben Beard, deputy director of the division of vector-borne diseases at the CDC, naming two grapefruit-flavored sodas. “If you drink Fresca or Squirt, you’ve drunk nootkatone,” Beard said.

Nootkatone works differently from previous classes of insecticides and can kill bugs that are resistant to DDT, pyrethroids and other common insecticides.