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.

The Legacy of Rachel Carson – Silent Spring?



According to The Guardian and every other source I consulted krill (zooplankton) have suffered an 80 percent decline beginning in the 70’s and currently the loss of krill is creating a starvation scenario for many marine animals from whales to penguins.


A recent article in The New York Times states that we have also lost 80 percent of the insects on the planet. Insects and krill (zoo plankton) are at the bottom of the food chain and the loss of these animals on land and in the water is nothing short of catastrophic because all other life forms including humans depend on them to survive.


On land the insect loss is directly tied to insecticide use. In the water, pollution (partially due to insecticide use), and increased industrial fishing for krill are culprits.


Human induced Climate Change is also a fundamental factor.


How is it possible that we are unwilling/unable to face the fact that we are actively engaged in the process of our own self – destruction?


I am writing this article on May Day. The cottonwood trees are feathered with pale green leaves, emerald green shoots and wildflowers abound. Gardens and fields are being tilled and planted. Adequate rain has blessed us creating seemingly unbelievable abundance. The river is a raging brown torrent ripping away the fragile shoreline; the acequias are running. The earth continues to celebrate renewal even as life on this planet becomes more threatened with each passing day.


Lately, I have been thinking a lot about the marine biologist and author Rachel Carson probably because I have had only one tree frog singing through the cottonwoods. I feel the loss of the abundance of these amphibians keenly, recognizing that pesticides are to blame. I have also spent time in gardening places where all sorts of deadly chemicals are still being sold much to my raging disbelief.


My relationship with Rachel Carson stretches back to childhood. I remember being so proud of the fact that I could read her book “The Edge of the Sea” at age twelve and understand everything she said. After moving from Monhegan Island to Southport Maine as a young mother, I discovered that Rachel Carson’s cottage was situated in the woods just behind my house. Although she died five years before I moved to Southport I suspect her influence on me lived on fueling my need to speak out as an environmental Earth activist, even now.


Rachel Carson, writer, scientist, and ecologist, grew up in the rural river town of Springdale, Pennsylvania. Her mother bequeathed to her a life-long love of nature and the living world that Rachel expressed first as a writer and later as a student of marine biology. Carson graduated from Chatham University in 1929, studied at the Woods Hole Marine Biological Laboratory in Massachusetts, and received her MA in zoology from Johns Hopkins University in 1932.


She began a fifteen-year career in the federal service as a scientist and editor and rose to become Editor-in-Chief of all publications for the U. S. Fish and Wildlife Service.


Carson wrote pamphlets on conservation and natural resources and edited scientific articles, but in her free time she wrote her first book, Under the Sea Wind. In 1952 she published her prize-winning study of the ocean, The Sea Around Us. She won a National Book Award, a national science writing-prize and a Guggenheim grant, which, with the book’s sales, enabled her to move to Southport Island, Maine in 1953 to concentrate on writing. This book was followed by The Edge of the Sea published in 1955. Together, these books created a biography of the ocean and made Carson publically famous as a naturalist and science writer. Carson resigned from government service in 1952 to devote herself to her writing.


Carson’s prophetic Silent Spring (1962) was written in response to the chemical pesticide use that became rampant after World War II. She also recognized that pesticides were killing her beloved birds. The book was first serialized in The New Yorker and then became a best seller, creating worldwide awareness of the dangers of environmental pollution.


Silent Spring suggested that the planetary ecosystem was reaching the limits of what it could sustain. She challenged the practices of agricultural scientists and the government and called for a change in the way humankind viewed the natural world. Carson courageously stood behind her warnings of the consequences of indiscriminate pesticide use despite the threat of lawsuits from the chemical industry and accusations that she was too emotional and grossly distorted the truth (criticisms I too have endured as a nature writer – at least I am in good company).


Carson was also attacked by the chemical industry and some in government as an alarmist, but continued to speak out to remind us that we are a vulnerable part of the natural world subject to the same damage as the rest of the ecosystem.


Outlining the dangers of chemical pesticides graphically, the book eventually led to a nationwide ban on DDT after Carson’s death, and sparked a movement that ultimately led to the creation of the US Environmental Protection Agency.


From my point of view probably the most important aspect of Carson’s writings is her view that human beings were just one part of nature distinguished primarily by their power to alter it, in some cases irrevocably.


Unfortunately, except for a few folks and some Indigenous peoples, these ideas with respect to species equality and the human ability to alter the earth’s ecology permanently are not part of the dominant cultural reality, especially in this country.


It is difficult for me to wrap my mind around the fact that up to the present we continue to export DDT and other toxic chemicals to third world countries like Mexico and South America, apparently believing that the toxicity in their water, soil and air will not have an effect on us while those of us who can afford it buy organic whatever.


Silent Spring was written in 1962 and almost 60 years later pesticide use continues unabated. It is rarely mentioned that now we have even more lethal chemicals to use in our backyards. As far as I can tell the EPA was left behind somewhere back in the last century. By conservative estimates we have lost 50 percent of the non-human species on earth. How can we continue to believe that we will be able to survive these losses? We are on the edge of our own extinction.


As I walk out the door into this glorious blue, green, and gold May Day I am heartsick. Every year we draw closer to ‘silent spring,’ the one without renewal.