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Caffeine As an Insecticide

By Jonathan Budzinski ; Updated September 21, 2017
Caffeine found in coffee and tea can be an effective home remedy for insect pests within the garden.

Caffeine is a compound most commonly found in coffee and teas. It is addictive to humans and is known for boosting energy levels for a short period of time. Studies show that caffeine is also toxic to insects and is becoming a new class of biochemical insecticides that holds minimal risks for humans.


Caffeine is a naturally derived biological substance that is found in various plants such as coffee beans and tea leaves. Its stimulating effects on the central nervous system have earned it recognition and popularity all across the globe. It is considered by the FDA to be a drug and food additive and is also a diuretic, causing the body to lose water.


In 1984, neurologist James A. Nathanson published an article for "Science" magazine stating that caffeine is produced within plants to ward off dangerous insect pests and is a natural insecticide. In his tests he observed that caffeine interfered with general behavior and growth of many insects and their larvae.


Mosquito infestations treated with caffeine will become inhibited in their development during early stages without introducing toxic chemicals into the local environment. As the primary carrier of the virus that develops into yellow fever, governments across the American continents are seeking alternative control agent different from the chemicals they have previously used.


Most chemical insecticides are highly toxic to humans and animals as well as insects. They can cause serious illnesses including some forms of cancer. Caffeine as a potential insecticide will reduce the threat posed from the use of manufactured chemicals to the human population.


Caffeine is not selective as an insecticide. It is lethal to most insects and, over time, even to the plants they are protecting. Caffeine does not decompose along with other substances within plants and will build within the soil over time. As this builds, the toxicity level of the soil raises to the point where the plant becomes unable to survive. This is why coffee plantations tend to erode after only a few decades.


About the Author


Jonathan Budzinski started his writing career in 2007. His work appears on websites such as WordGigs. Budzinski specializes in nonprofit topics as he spent two years working with Basic Rights Oregon and WomanSpace. He has received recognition as a Shining Star Talent Scholar in English while studying English at the University of Oregon.