Wanting to only use chemical-free products, it make sense then to use a natural insect repellent. But I have used some natural repellents that have been quite unimpressive; the female mosquitoes land on my skin in laughter, “Ha, ha, ha, sucker!”
You can find lots of homemade formulations suggested online, but an endless list of essential oils, vegetable matter and stinky concoctions leaves one confused. Which one really works the best? So I did some research of real, scientific journal article studies to see what natural ingredients are most effective.
What Attracts Mosquitoes to Some People More Than Others?
Apparently 20% of people are more likely to be bitten by mosquitoes based on factors that cannot be changed, such as genetics. Here are things you have no control over followed by some things you can do to avoid attracting mosquitoes.
Genetic and Unchangeable Factors:
- Type O Blood – Those with type A blood are the least attractive to mosquitos, type B is in the middle.
- Fast metabolism of cholesterol which by-products are expelled through skin surface.
- Those with higher body temperatures.
- Pregnant women and large people, because they give off more carbon dioxide which attracts mosquitoes and can be detected up to 164 feet away. Pregnant women also have a higher average body temperature.
- Those who release more steroid by-products, uric acid, lactic acid and ammonia through the skin via sweating and/or other natural compounds through breathing.
- Those who have an increased amount of a certain bacteria, especially Staphylococcus epidermidis, on their skin.
Factors You Can Change or Avoid to be Bitten
- Avoid being in mosquito territory after exercising because of higher body temperature, more exhalation of C02 , increased amounts of expelled lactic acid and bacteria-causing body odor bacteria on the skin.
- Beer drinkers – They haven’t pinpointed why, but a study has found that only one 12-oz beer is all it takes to make you more attractive to mosquitoes – hmm, do they get beer goggles too?
- Mosquitoes are attracted to dark colors, so avoid wearing dark colored clothing especially black, dark blues and reds.
- Avoid wearing perfumes or heavily-scented soaps and shampoos that attract mosquitoes.
Chemical Insect Repellents
Here are some of the common chemical-based insect repellents used for mosquitoes, ticks, fleas, chiggers, mites, black flies and other biting insects.
- DEET (N,N-diethyl-m-toluamide): Registered pesticide, developed in 1946 and first used by the military during jungle warfare. Approved for civilian use in 1957. Considered safe with normal use by the EPA and CDC, but possible side effects and warnings include: skin and eye irritation, seizures, insomnia, should not to be used on infants under 2 months old or pregnant women, can affect central nervous system (similar to effects of nerve gas). Damages plastic and synthetic materials – i.e., if it gets on your binocular grips, they will turn to goo.
- Picaridin: Also named Icaridin, Bayrepel and KBR 3023, (2-(2-hydroxyethyl)-1 piperidinecarboxylic acid 1-methylpropyl ester). Approved in the US in 2005, but used worldwide since 1998. Is odorless, lightly scented, just as effective as DEET but does not irritate skin and damage plastics as DEET does.
- IR3535 (3-[N-Butyl-N-acetyl]-aminopropionic acid, ethyl ester): Chemical used in Avon’s Skin-So-Soft Bug Guard Spray. Much less effective than DEET or Picaridin. Approved in the US by the EPA in 1999. The IR3535-based repellent protected for an average of 22.9 minutes.
- Permethrin: For use as an insect repellent on clothing and gear (not to be applied to skin). Also used as a pediculicide for head lice and scabies. Classified by the EPA as a likely human carcinogen, but considered safe when exposed to recommended low-doses. Highly toxic to cats, fish and other aquatic organisms. First registered with the EPA in 1979 for use on cotton.
- Metofluthrin: Used in clip-on diffusers to emit a vapor cloud of the chemical repellent as protection around you. As a neurotoxin, it is not to be applied directly to skin. Mostly effective towards mosquitoes if you are sitting still in one location, i.e., reading a book on the back porch. Not good for use during activities such as hiking, sports or when you will be moving around a lot. Approved by EPA in 2006.
Plant-Based Natural Insect Repellents
Many plant extracts have been identified as having insect-repellent effects and there has been increasing research in the last decade proving plant-based insect repellents are just as, if not more effective than DEET. For example, a field evaluation in the Bolivian Amazon demonstrated a eucalyptus-based repellent gave 96% protection for 4 hours vs DEET providing only 84% protection for the same amount of time. Some essential oils work well at masking chemicals from your body that attracts mosquitoes or simply acts as an irritant to the mosquito when detected.
Best Plant Essential Oils Scientifically Proven to Repel Mosquitoes, Biting Flies, Ticks and Other Insects
To start with, I have included EPA-registered plant-based insect repellents (biopesticides) with natural pesticide ingredients: Catnip Oil, Citronella, Oil of Lemon Eucalyptus and p-Menthane-3,8-diol (active compound in oil of lemon eucalyptus, also referred to as PMD). What does it mean to have and EPA-registered product by a company? It means that the company has provided the EPA with technical information based on scientific testing guidelines and approved study methodology on the effectiveness of the product against mosquitoes and/or ticks.
Oil of Lemon Eucalyptus (OLE, Citriodiol): From the Australian gum species, Corymbia citriodora also known as Eucalyptus citriodora. The active ingredient is para-menthane-3,8-diol, also referred to as PMD, refined from citronellal. When refined to increase the PMD content, it is designated as OLE (oil of lemon eucalyptus) or Citriodiol in the US. It is an EPA-registered biopesticide (derived from natural ingredients) and endorsed by the CDC.
Products containing oil of lemon eucalyptus are the most effective plant-based repellents available. It has a pleasant scent and feel without any plasticizing properties. Warnings: Do not used on children younger than three years old. Like other essential oil products, it can cause skin irritation in higher concentrations.
Best Lemon Eucalyptus Oil Repellent: Repel Lemon Eucalyptus Repellent contains 30% Oil of Lemon Eucalyptus with a concentration of 65% PMD.
In an evaluation by Consumer Reports of 10 repellents, both chemical and natural, Repel Lemon Eucalyptus Insect Repellent scored a 97/100 rating. It worked for at least 6 hours and was comparable to a 25% DEET product by OFF.
“This stuff is great! I took this with me on a 2.5 week trip through the amazon jungle in Ecuador. I didn’t use any DEET at all and…only got 3 bites the entire time there.” – Isc449
Catnip Essential Oil: Nepetalactone is the organic compound in catnip (from the mint family) which has been found to repel mosquitoes 10x more effectively than Deet. The study was conducted by Iowa State University in 2001 in a lab. Since then, there have been more studies demonstrating that catnip essential oil works as an effective natural mosquito repellent, however, I have yet to find any big-name products using it as an active ingredient. Catnip oil was registered by the EPA as a biopesticide in 2009 by DuPont as “Refined Oil of Nepeta Cataria” in 7% and 15% oil and lotions, but again, I have yet to find any commercial products from the company.
Perhaps there is more research being conducted since I did read some reports that the toxicity of catnip oil is largely unknown and it can cause minor skin irritation. I grow catnip for my cats so the next time I venture out into the woods, I’ll bring along some leaves to crush and smear on my clothes and skin as a test.
Best Catnip Essential Oil Repellent: Because there is still ongoing research, no big-name-brand commercial products are out on the market possessing EPA-registration, validating efficacy. There is an essential oil blend called Bug Off Synergy that includes catnip oil with a lot of positive reviews. You can, of course, purchase catnip essential oil and then dilute it to a 10% concentration to start with, but the oil itself is a little expensive, around $15-$20 per 1/2 ounce. I would consider adding catnip oil as one of the components to my homemade mosquito repellent. As with most essential oils, never apply 100% pure catnip oil to your skin.
The synergy blend is not diluted, so you will want to dilute it with rubbing alcohol or witch hazel in a spray bottle. Try 10 drops in a 4 ounces and fill with witch hazel or alcohol to start with and boost the concentration later if needed. You can also add a carrier oil such as soybean or coconut oil to make it last longer: Bug Off Synergy Essential Oil Blend.
“Bug Off worked well on a recent camping trip. I applied it every few hours as recommended & mosquitoes stayed away.” -Not Bitten
Citronella Essential Oil: Derived from two species of citronella grass, Cymbopogon nardus and Cymbopogon winterianus. Has been registered for use as a plant-based insect repellent since 1948. EPA reports no toxicity concerns when applied to skin, however, there is some concern about it causing increased heart rates in some people.
Citronella appears to be the least effective oil when applied by itself with no other ingredients. A study by the University of North Carolina found that citronella insect repellent products provided only 19 minutes of protection after application. However, as I will discuss in our next article, adding vanillin and/or soybean oil as well as other essential oil repellents to citronella is likely to prolong protection time compared with citronella oil alone. In Anopheles and Culex mosquitoes, a combination of citronella oil and vanillin demonstrated a comparable protection time against DEET.
Best Citronella Essential Oil Repellent: California Baby Bug Repellent Spray is an effective natural insect repellent especially for babies, children and adults with sensitive skin.
The active ingredients include citronella, lemongrass and cedar essential oils and contains no nut oils, gluten, soy, oat or dairy ingredients. Repels mosquitoes, ticks and biting flies.
“Someone brought this for us to try and it worked so well we used it the whole time…Not a single bug bite after 3 days of camping.” – Kate
These next two oils have not been EPA-Registered as natural repellents, but there has been a lot of studies proving their efficacy as very good alternatives to chemical repellents such as DEET.
Soybean Oil: Soybean oil based repellents have shown to be more effective than other natural repellents without soybean oil. It seems to increase the duration of protection time when added to other essential oils such as citronella. In one study, a 2% soybean oil based repellent (Bite Blocker for Kids) was as effective as 4-6% DEET products: OFF! Skintastic for Kids and OFF! Skintastic, respectively, lasting 1.5 hours. It far outperformed a 10% citronella formula (Natrapel) which only provided protection for 20 minutes. Look for products that use non-GMO, organic soybean oil.
Best Soybean Oil Based Repellent: Bite Blocker Xtreme is the best soybean-oil based insect repellent containing soybean oil, geranium oil and castor oil as the active ingredients. It is waterproof and sweatproof, providing up to 8 hours of protection.
Neem Oil: Pressed from seeds of the Neem Tree (Azadirachta indica). Several studies have proven Neem oil to be very effective as an insect repellent, even more effective than DEET, according to the US National Research Council. In one study, a mixture of 2% neem oil with coconut oil provided 96-100% protection for 12 hours from the bites of all Anopheline species. But as the case with many other essential oils, they do not protect equally across all mosquito species. The same formula protected 85% from Aedes, 37.5% from Armigeres and anywhere from 61-94% against Culex spp..
Best Neem Oil Repellent: This product isn’t solely marketed as a repellent, but you can apply directly to skin or combine with coconut oil as the study mentioned above did. The only drawback is it does have a strong scent, some describe it as burnt peanuts or like garlic, which is why diluting it to a 2% concentration mixed with coconut oil would help. I would also add it in combination with other repellent essential oils: 100% Pure Neem Oil.
Even though these are natural repellents, be sure to read all precautionary statements on the label. Some can cause moderate eye irritation. In rare cases, it may irritate skin so test a small area first. Do not allow children to apply any repellent to themselves.
What else can I do to keep insects away from my house and backyard?
- Remove standing water from anything that can accumulate water around your house such as gutters, flowerpot bottoms, tires, lids, etc.. to prevent insects from breeding.
- Change out water from landscape features, bird baths or pools that lack circulation at least once a week.
Be sure to also check out our homemade mosquito repellent recipes you can make with different essential oils from mosquito repellent plants to suit your needs.
Have you tried any natural insect repellents, good or bad? What has worked for you? Let us know in the comments below. 🙂