Whether you’re the kind of person who likes to go on long excursions in the bush or simply enjoy sitting outside on a hot summers day, one thing’s for sure: remaining bug-free is of upmost importance. So when I come across studies that find things like coconut oil repels insects better than DEET, I get really excited, because protecting our health while also staying bug-free is a win-win in my opinion.
The chemical concoctions that make up most standard bug repellents wreak havoc on the nervous system. Aside from the controversial chemical, DEET, these repellents also contain ingredients like fragrance, Dimethicone, sodium benzoate as well as butane and propane. All highly neurotoxic.
Thankfully, you can still get protection from unwanted bugs by utilizing natural insect repellents like coconut oil and different essential oil blends.
But before getting into that, I wanted to give you a little background on DEET, and why it should be avoided (or at the very least, how to apply it properly to reduce direct exposure).
What is DEET?
DEET (N,N-diethyl-meta-toluamide) is the most widely used insect repellent pesticide in North America. The chemical deters insects like mosquitoes, black flies, fleas and ticks, and prevents the spread of insect-borne diseases like West Nile Virus, Zika Virus, Malaria, and Lyme Disease.
DEET was first developed by the United States Army in 1946 and was approved for public use in 1957. While the warnings on labels say to not ingest, that’s a bit difficult if you’re spraying it directly on your skin or inhaling the vapors from the sprays. For a chemical that is also known to melt plastic, how can we be so quick to trust those that make claims about its safety?
I don’t know about you, but I wouldn’t be spraying pesticide on my skin just to be protected from bugs if safer alternatives exist.
Dangers of DEET
DEET is not without controversy or side effects. In fact, regular DEET use is linked to side effects like rashes, skin irritation, numbness and burning in the lips, nausea, headaches, dizziness and trouble concentrating.
Most of the serious side effects caused by DEET involve long-term, heavy, frequent, or whole-body application of the repellent (1). Unfortunately, we’re bombarded by so many chemicals on a day-to-day basis that adding in another toxic threat like DEET can be icing on the cake for the trigger of many different health concerns.
In some cases, DEET alone can cause the following conditions or reactions:
Many studies have found DEET to be toxic to the central nervous system. Vincent Corbel from the Institut de Recherche pour le Développement in Montpellier, and Bruno Lapied from the University of Angers, France, led a team of researchers who determined the mode of action and toxicity of DEET (2).
According to Corbel, DEET “inhibits the activity of a key central nervous system enzyme, acetylcholinesterase, in both insects and mammals.” (3). This is the same mode of action used by organophosphate and carbamate insecticides.
It is often the case that DEET is combined with these insecticides. But this isn’t a good thing. DEET interacts with carbamate insecticides to increase their toxicity, which means bad news for our nervous system.
In some instances, DEET has been found to induce seizures in children. According to a case analysis published in Human and Experimental Toxicology, clinical reports of children under 16 years old who suffered from brain damage indicate that symptoms can be caused by the ingestion of DEET, as well as repeated or even brief exposure to the insect repellent. The most common symptom among the reported cases was seizures, affecting over 72 percent of the patients. These symptoms were significantly more frequent when DEET products were applied to the skin.
The researchers of the study concluded that “repellents containing DEET are not safe when applied to children’s skin and should be avoided in children.” (4).
DEET is known to create allergic skin reactions like redness, rash, swelling and hives, especially when on the skin for extended periods of time. One case study found that some people may even go into anaphylaxis from exposure to DEET. In the case of one 53-year-old woman, symptoms like skin redness, fever, and blistering appeared after an insect repellent containing DEET was applied topically. The next time she used a product containing DEET, she developed hives and swollen eyes, and had to call 911 (5).
Another case study involved a 22-year-old man who developed hives immediately after applying insect repellent and coming into contact with those who had used DEET-containing repellents (6).
Anecdotal reports of allergies to DEET can be found all over the internet, as a simple Google search will provide.
While the results are mixed on whether DEET causes cancer, there is some evidence that it contains carcinogenic properties that can alter our DNA if inhaled or applied to the skin. One study from Germany found that when cells from tissue biopsies were exposed to DEET for 60 minutes, the pesticide produced potential carcinogenic effects in human nasal mucosal cells (7).
Another study found that DEET specifically stimulates endothelial cells that promote angiogenesis (the formation of new blood vessels), which increases tumor growth. As cited by researchers in the article, “Considering the environmental pollution induced by DEET worldwide and its presence in drinking water sources, new water treatment technologies are needed for its elimination. Finally, risk assessment of DEET should now be implemented in humans in order to provide safe conditions of use of this insect repellent.” (8).
4. Environmental Impact
As mentioned above, DEET is widespread in our environment. Not only is it present in water, but it’s in the air, too. For these reasons, DEET is toxic to birds, fish, aquatic invertebrates and other insects.
A recent U.S. Geological Survey report on water contaminants listed DEET as one of the compounds most frequently found in the nation’s streams. Not only does this negatively affect the health of our lakes, rivers, and streams, but it can greatly impact the health of the ecosystem as a whole.
According to the National Pesticide Information Center, DEET is found in wastewater, as well as in places where wastewater moves into other bodies of water. Even low concentrations of DEET produce a slight toxic effect in cold water fish. DEET can then enter the bodies of other animals (like humans) who consume those fish.
DEET takes a long time to break down, so it can remain in the environment for many years.
For the sake of your body, and the environment, it is best to steer clear of DEET (especially if you’re just going to the park, where bug contact is minimal).
If you must apply DEET, make sure you follow these directions as provided by the Centers for Disease and Control (CDC):
– Do not apply to skin that is cut, wounded or irritated
– Do not apply to hands, or close to the eyes or mouth
– Do not use on young children
– Do not use under clothing
– Do not over-apply
– If you must apply to exposed skin, make sure the areas of exposed skin are kept to a minimum by wearing long sleeves and pants
– Wash the product from your skin and clothes with soap and water after use
Coconut Oil Repels Insects Better Than DEET
Fortunately for us, we don’t need to depend on DEET to repel blood-sucking insects. And it could be as easy as slathering on some coconut oil before heading out the door.
According to the new U.S. Department of Agriculture (USDA) study, compounds derived from coconut oil repel insects better than DEET.
The study, published in Scientific Reports, identified specific coconut oil fatty acids that have strong repellency and long-lasting effectiveness against disease-transmitting insects like mosquitoes, ticks, biting flies and bed bugs.
Lead researcher, Junwei (Jerry) Zhu, with the ARS Agroecosystem Management Research Unit in Lincoln, Nebraska, found that the coconut oil compounds were effective against biting flies and bed bugs for two weeks. Not only that, but coconut oil had a lasting repellency against ticks for over a week in laboratory tests. When higher concentrations of coconut oil compounds were topically applied, repellency against mosquitoes was even stronger.
Zhu emphasized that coconut oil itself is not a repellent, but the coconut oil-derived free fatty acid mixture — lauric acid, capric acid and caprylic acid as well as their corresponding methyl esters — provides strong repellency. Field trials showed that this all-natural formula, when encapsulated into a starch-based formula could provide protection to cattle against stable flies for up to 96 hours (4 days).
While DEET was only 50 percent effective against stable flies, the coconut oil compound was more than 95 percent effective.
DEET lost its effectiveness after three days when tested against bed bugs and ticks. Coconut oil, on the other hand, lasted for about two weeks. Coconut oil fatty acids also provided more than 90 percent repellency against mosquitoes, including the species that can transmit the Zika virus.
According to Zhu, this is the only known natural insect repellent that offers long-lasting protection.
Coconut Oil Insect Repellent Recipe
While coconut oil repels insects better than DEET, you can make the formulation even stronger by adding insect-repelling essential oils.
You have two options when making your recipe. You can either purchase a spray bottle and add essential oils and liquid coconut oil, or you can mix up solid coconut oil with essential oils in a container with a screw-on lid. With both versions, you’ll be able to apply directly to your skin. You’ll just have the option of either spraying onto your skin and then rubbing it in, or just taking the mixture out of the container by hand and rubbing onto your skin.
The following essential oils are effective against blood-sucking insects:
– Citronella (Cymbopogon winterianus)
– Lavender (Lavandula augustifolia)
– Clove (Eugenia caryophyllata)
– Lemongrass (Cymbopogon flexuosus)
– Lemon Eucalyptus (Eucalyptus citriodora)
– Catnip (Nepeta cataria)
– Virginian Cedarwood (Juniperus virginiana)
– Rose Geranium (Pelargonium roseum)
You can use a combination of the oils, or use them singularly. Dilute 10 drops of your essential oil into four ounces of coconut oil in a spray bottle (make sure you use liquid coconut oil for the spray bottle) or screw-lid (coconut oil that hardens at temperatures cooler than room temperature can be used for this purpose). Either shake (spray bottle) or mix (screw-lid) the essential oils into the coconut oil, and use as needed.