Types of Chemical and Natural Mosquito Repellents
Keeping the Mosquitoes Away From You
Avoiding those bloodthirsty mosquitoes when outdoors can be a challenging task. If you don't protect yourself, you can be a very inviting meal for these critters. There are ways to avoid having all of those itchy, red welts all over your body. Using repellents to steer the mosquitoes away from you can help. There are repellents on the market as well as natural ways to repel mosquitoes.
The first line of defense to avoid mosquitoes is to stay away from activities and items that can attract them. By avoiding these things, the mosquitoes will find you less attractive meal.
- Avoid dark clothing. Many mosquitoes use vision to locate hosts from a distance. Dark clothes and foliage are initial attractants.
- Emit as little carbon dioxide as possible. You give off more carbon dioxide when you are hot or have been exercising. A burning candle or other fire is another source of carbon dioxide.
- Emit as little lactic acid as possible. You release more lactic acid when you have been exercising or after eating certain foods (e.g., salty foods, high-potassium foods).
- Avoid floral or fruity fragrances In addition to perfumes, hair products, and scented sunscreens, watch for the subtle floral fragrance from fabric softeners and dryer sheets.
- Skin temperature is a key. The exact temperature depends on the type of mosquito. Many mosquitoes are attracted to the slightly cooler temperatures of the extremities. About the only way to avoid this is by covering your arms and legs with protective clothing.
Chemical Insect Repellents
Probably the most commonly known insect repellents contain the chemical DEET, which stands for N,N-diethyl-meta-toluamide. Repellents containing DEET can be applied to the skin or clothing to prevent bites from mosquitoes and ticks.
It is believed that DEET works by blocking the insect olfactory receptors for 1-octen-3-ol, which is the substanc contained in human sweat and breath. Insect repellents usually contain concentrations of DEET ranging from 10 to 35 percent. Repellents containing 20 to 35 percent concentrations are expected to keep the bugs away for six to 12 hours. Concentrations of less than 10 percent offer protection for one to three hours.
DEET is not recommended for infants less than two months old. It is also not to be applied to damaged skin. In some cases DEET can cause skin irritations or reactions. Another insect repellent, icaridin has been reported to be as effective as DEET without the irritation associated with DEET. According to the World Health Organization, icaridin "demonstrates excellent repellent properties comparable to, and often superior to, those of the standard DEET."
When applying any insect repellent you should follow these guidelines:
- Always read the directions and apply accordingly.
- Do not use any repellent that has not been approved by the EPA.
- Watch for allergic reactions.
- Do not apply repellent to mouth, eyes, cuts, wounds or sunburned skin.
- When applying to your face, spray it on your hands and then rub on your face.
- Only apply repellent to exposed skin.
- Children should not apply insect repellent. Only adults should apply to children.
- Apply only as often as label indicates.
- Always wash repellent off of skin when you come inside.
- Keep in mind, some things lower repellent effectiveness such as sunscreen, swimming, rain, sweat, and evaporation.
Is Catnip More Effective than DEET?
Researchers at Iowa State University claim that nepetalactone, the oil contained in catnip, is ten times more effective at repelling mosquitoes than DEET. For the study, groups of 20 mosquitoes were put in a two-foot glass tube, half of which was treated with nepetalactone. After 10 minutes, only about four (20 percent) mosquitoes remained on the side treated with a high dose of the oil. In a low-dose test an average of 25 percent or five mosquitoes remained. In contrast, tests with DEET found that there were 40 to 45 percent or eight to nine, mosquitoes remaining on treated side.
Researchers hope that this study will lead to development of a nepetalactone insect repellent in the future. Catnip is primarily known for the stimulating effects it has on cats. Let's hope it doesn't make people wildly chase balls of yarn and climb up the curtains!
If you are uncomfortable spraying chemicals on your body then there are some natural mosquito repellents. These might not be as effective as DEET and will need to be applied more often. It is important to note that even though these are natural substances, some people can be sensitive to certain plant oils and high concentrations of these oils can be toxic.
- Lemon Eucalyptus Oil
- Cinnamon Oil
- Citronella Oil
- Rosemary Oil
- Lemongrass Oil
- Cedar Oil
- Peppermint Oil
- Geranium Oil
- Castor Oil
- Clove Oil
While citronella candles won't keep swarms of mosquitoes from entering your backyard, they do offer some protection. One study compared the ability of commercially available 3% citronella candles, 5% citronella incense, and plain candles to prevent bites by Aedes mosquitoes under field conditions. People near the citronella candles had 42% fewer bites than the control group who had no protection. However, burning ordinary candles reduced the number of bites by 23%. The study concluded that the efficacy of citronella incense and plain candles were not that different. The ability of plain candles to decrease biting may result from their action as a decoy source of warmth, moisture, and carbon dioxide.
Types of Vegetation that Repel Mosquitoes
Many of the essential oils that act as mosquito deterrents can also work to repel mosquitoes in their vegetative form. These grasses and plant can be planted in your yard, garden and landscaping to add a little mosquito protection. However, don't expect the entire mosquito population to fly away and leave you alone.
- Citronella grass is used to make the oil that is contained in candles that can be burned to repel mosquitoes. Citronella grass is actually a tropic plant that grows to be six feet tall, so it might not be practical in the average suburban backyard.
- As we found out earlier, catnip is derived from a plant and is most commonly used to drive your cat crazy. However, planting catnip plant near your patio or deck will help repel mosquitoes.
- The rosemary garden herb also has oil that repels mosquitoes. These are tropical plants and do not grow well in colder climates. However, you can grow them in a pot and take them inside during the winter.
- With their yellows, oranges and reds, marigold flowers may look pretty but don't smell particularly pretty to humans or insects. They are a good plant for repelling mosquitoes as well as insects that can attack vegetable plants and aphids.
- Horsemint has a scent similar to citronella, which mosquitoes don't like. Horsemint grows wild in most of the Eastern United States, from Mexico, Texas up to Minnesota to Vermont. It is partial to sandy soils.
- The ageratum bedding plant contains coumarin, and mosquitoes detest the smell. It is used in the perfume industry and is even in some commercial mosquito repellants. Ageratums are annuals, and they come in a muted blue and white that compliments most other plantings.
- There are two types of plants known as mosquito plants. One is a member of the geranium family that was genetically engineered to incorporate the properties of citronella. Since Citronella only grows in tropical places, this plant was created to bring the repellant properties of citronella into a hardier plant. The other kind of mosquito plant is agastache cana, which common names include Texas hummingbird mint, bubblegum mint, giant hyssop, or giant hummingbird mint.
Choosing a Repellent that is Right for You
Insect repellents do not protect all people in the same way. The effectiveness of a repellent depends on the mosquito species that is biting as well as the age, sex, level of activity, and attractiveness of the human using the repellent. Consider the following when choosing a repellent:
- Are you in an area where you know that mosquito-borne diseases are present?
- Are there a lot of mosquitoes around?
- How much time will you be spending outdoors?
- Will you be around heavily vegetated, humid areas during the day?
- What types of activities will you engage in such as swimming, exercising, etc.?
- What is the weather like? Is it humid and the temperature high?
Other Ways to Avoid the Mosquitoes
Make sure your yard doesn't contain any breeding areas for mosquitoes. Female mosquitoes look for areas with still, stagnant water to lay their eggs. Empty standing water from pots, children's pools, clogged gutters or any areas that are prime breeding grounds for mosquitoes.
Investing in a mosquito trap to place on your property can also reduce the mosquito population around your home. These traps can attract mosquitoes in an area as large as 1.5 acres. They attract mosquitoes by emitting a plume of carbon dioxide together with other mosquito attractants such as sugary scents, lactic acid, octenol, warmth, water vapor and sounds. By mimicking a mammal's scent and outputs, female mosquitoes are drawn toward the trap, where they are typically sucked into a net or holder by an electric fan where they are collected. It is a safe and clean alternative to mosquito repellents.