Most people know corn starch can be used for cooking, as a stain remover and as a deodorizer. Now they can add insect repellant to corn starch’s expansive list of applications.
The U.S. Department of Agriculture Agricultural Research Service has announced that its scientists in Peoria, Ill., are using the starch to make products that can fight insects, including mosquitoes.
Researchers convert starch into a class of materials known as amylose-inclusion complexes. The complexes can be combined with essential oils from plants toxic to mosquitoes, creating an emulsion. Once blended, the complexes surround the oil, protecting it from heat and oxidation, which can reduce its potency.
Safe for the environment but toxic to mosquito larvae, the emulsion can be applied to larvae habitats, such as water catch basins and old tires. The substance disperses in the water, allowing it to contact and kill larvae. Lab tests showed the emulsion killed the larvae of yellow fever mosquitoes in 24 hours.
According to the USDA’s announcement, researchers envision using the emulsion to help control mosquito populations and prevent diseases like West Nile virus, yellow fever, dengue and Zika.
“This is a terrific development,” said Tony Banks, senior assistant director of agriculture, development and innovation for Virginia Farm Bureau Federation. “As an insecticide, this type of product could be environmentally safer and pose fewer exposure risks. Naturally, this technology could lead to greater demand for corn as more starch-based products are developed.”
With humidity and rainy weather, Virginia’s spring and summer make an ideal climate for mosquitoes, which are harmful to humans and animals and spread debilitating, sometimes fatal diseases.
The Centers for Disease Control and Prevention reported Virginia had 1,319 cases of mosquito-borne diseases between 2004 and 2016. The most prevalent such disease in Virginia is West Nile virus.
Farmers and their animals spend a lot of time outdoors and can be especially vulnerable to mosquito-borne diseases. Many farms have sources of standing water that make ideal breeding grounds for the pests, including ponds, containers and drums, and ditches that collect water. This new technology could lead to new alternatives for controlling mosquito-borne diseases that affect humans, livestock and pets, Banks said.
“Mosquito-borne diseases can affect livestock production by causing weight loss, lost reproduction and death,” he added. “Vaccines are not foolproof, so we need to have a variety of measures for controlling pests and diseases.”
