Deet, a Hidden Killer?

We all know that ticks and mosquitos are a problem here in Maine. Recently, when I went to the supermarket to buy a non-toxic insect spray to use around my door I was astonished and dismayed to discover that all but one spray used Deet (I came home and ordered lemon eucalyptus oil). Granted, Deet is the most widely used insect repellent in the U.S. It has been around longer than any other active ingredient, and many scientists say it’s the ‘gold’ standard for all repellents.

Deet known to chemists as N,N – Diethyl – meta – toluamide is a yellowish liquid that, when applied to skin or clothing, repels a number of biting insects, including mosquitoes (some sources say it does not repel mosquitos at all!), ticks, and fleas. The chemical was created by USDA chemists in the 1940s for use by the U.S. military. It has been commercially available since 1957 and has since become commonplace.


“How this chemical kills insects remains a mystery to scientists.”


Does anyone besides me find this statement alarming?


Deet is a pesticide that has been banned in many countries in Europe – but is considered safe in US. Why? There is no direct (key word) relationship between D and neurological disorders say the “experts.”


Many people routinely use this product on their skin or clothes – What we do know is that this product kills amphibians, fish, and reptiles along with insects – and almost immediately ends up in the nearest water source. We all drink it and don’t know it.


Although Deet is not supposed to stay in the environment for long we have absolutely no idea what damage it does to the rapidly disappearing helpful insects etc. while it’s there.


After living in New Mexico where bees, butterflies and other insects are still relatively common pollinators I wondered why the loss of bees is so much more severe here in Maine. This year, although my many fruit trees were all blooming profusely I never saw more than a few bumblebees disappearing into the flower heads for nectar (I used to be able to stand under my fruit trees listening to a deafening collective bee hum).


To answer the above question I looked to the use of pesticides. While living in New Mexico I lived in a desert where grass was absent and the common garden variety of deadly insecticides like Round –Up weren’t needed to control pests. Annoying mosquitos were only found at the river’s edge and Lyme ticks were non – existent. No need to sell Deet in the desert. Of course agribusiness still uses other deadly pesticides, although not in Rio Arriba County where I live because people, especially Indigenous peoples, have banned the use of these products. Each Pueblo sells pure (and the most delicious) honey from honey bees that have not been exposed to antibiotics.


I reached the tentative conclusion that the use of common pesticides like Deet might be responsible for the shocking absence of pollinators here; at least that’s my present hypothesis.


I thought about biologist/scientist/environmentalist Rachel Carson’s prophetic book Silent Spring  that was written almost 60 years ago. Deet was one of the chemicals that environmentalist/scientist/biologist Rachel Carson objected to.


Written in response to all rampant chemical pesticide use after World War II. Silent Spring suggested that the planetary ecosystem was reaching the limits of what it could sustain. Rachel challenged the practices of agricultural scientists, the government, and called for a change in the way humankind viewed the natural world, warning the public about the dire consequences of indiscriminate pesticide use.


Maybe we should have listened.