Top 5 Ways to Repel Insects

Of course, the best way to avoid being bitten by a bug is to cover up your body as much as possible. But in the sweltering heat, this might not be the most appealing option. A good alternative is to wear insect-repellent clothing, particularly clothing containing permethrin, a synthetic chemical insecticide.

Permethrin-treated clothing can remain effective for several months. But washing it can reduce its effectiveness. If you wear and launder permethrin-treated clothing every day, it will remain effective for about two weeks. You should reapply permethrin after about five washings.

On the down side, the jury is still out on the safety of permethrin. While it's not toxic when applied to clothing, it should not be applied directly to the skin. Although the Environmental Protection Agency asserts that the benefits of permethrin outweigh the risks, it lists the insecticide as a likely carcinogen if handled improperly [source: EPA].

Wearing floral or fruity smelling perfume, body lotions and sunscreen or using scented shampoos and body washes can increase the likelihood of a bug bite. If you smell like flowers or fruit, an insect is likely to confuse you with vegetation and will be attracted to your scent [source: Peterson]. Even subtle fragrances that come from products like dryer sheets and fabric softeners can attract insects. Washing your clothing in fragrant detergents might also entice bugs.

As an alternative, you can use scentless soaps and detergents. You'll be fresh and clean but not a floral or fruity smorgasbord for curious insects.

Like we mentioned before, mosquitoes can detect humans from 100 feet (30.5 meters) away. If you're out in the heat and you've been sweating, you'll have a stronger scent and be even more vulnerable to bites. If you've been eating foods that contain high levels of salt or potassium, your body will produce an increased level of lactic acid. Mosquitoes and other insects are attracted to the smell of lactic acid, so your scent will be even more appealing to them [source: DeGaborik].

To avoid this, stay away from food that contains high levels of salt and potassium. This will reduce the amount of lactic acid that your body produces and thus decrease the likelihood that your scent will attract insects.

If you're looking for a natural way to repel insects, oil of lemon eucalyptus is one answer. Its active ingredient is p-menthane-3,8-diol (PMD). This EPA-approved repellent provides the longest-lasting protection of all plant-based products [source: CDC]. It provides protection similar to products that contain low levels of DEET (a chemical we'll discuss on the next page). Oil of lemon eucalyptus poses no threats to the environment, and the only potential risk to your health is eye irritation if you apply the product directly to your face. It's effective in repelling mosquitoes, biting insects and gnats.

Other natural oils effective in repelling insects include citronella, cinnamon, castor, rosemary, lemongrass, cedar, clove, geranium and peppermint oils.

Although they might not have the best reputation, products that contain the chemicals DEET (N,N-diethyl-m-toluamide) or picaridin (KBR 3023) are the most effective insect repellents. While DEET is not a carcinogen, DEET products get a bad rap because long-term exposure may cause moodiness, insomnia and impaired cognitive function [source: Peterson]. Studies have shown that after high concentrations of continued exposure, DEET can cause hypertrophy of the liver and kidneys as well as stimulation of the central nervous system which can cause tremors and seizures [source: Extonet]. DEET products also have the potential to damage the water supply. DEET can not only harm aquatic life-forms, but it can also enter the drinking supply as runoff if farmers mishandle the product. The Environmental Protection Agency (EPA)monitors DEET products and only approves those that are effective and won't cause you or the environment damage.

Citing numerous scientific studies, the Centers for Disease Control and Prevention asserts that DEET products provide the longest-lasting protection against insects [source: CDC]. Depending on the amount of DEET in a product, it can repel insects for an average of three to eight hours [source: EPA].

Here's a guide for the length of time for the effectiveness of various DEET concentrations: