Tick and Mosquito Protection

Tick and Mosquito Protection

By ArcticAbn

First off let me say that no single repellent agent that you may purchase is 100% effective. Moreover, many of the agents out there may be effective against one or more types of insects yet less effective against other types.

All insect repellents essentially work in the same manner. They form a barrier between you and the insect. They are a repellent not an insecticide. I should not have to say this but here is a safety note:



Insect repellents are designed to do just that repel insects. Repellents are applied to the skin. The repellent works by repellents work by evaporation, creating a shield a few inches above the area of application. The presence of the repellent vapor confuses insects so they can’t locate a target host. The interaction of the body (sweating and heat) causes the repellent to evaporate. Insecticides are designed to kill insects. Therefore, most if not all are considered hazardous to humans as well. Contact with insecticides should be avoided.

Through various studies the Center for Disease Control (CDC) and the Department of Defense (DoD) developed what is termed the DoD Repellent System. The DoD Repellent System is comprised of two different types of barriers. There are only two chemicals approved for use in the DoD protection system. When used together, they provide nearly 100% protection from ticks, mosquitoes, chiggers, fleas and other marauding insects. Both of these repellents are approved by the CDC and by the Environmental Protection Agency (EPA). They are N-diethyl-meta-toluamide more commonly known as DEET and Permethrin.

The use and application method of both agents is different and to be effective must be used in combination with each other. DEET is a repellent and Permethrin is an insecticide.

What is DEET, is it safe, and how does it work?

DEET (chemical name, N,N-diethyl-meta-toluamide) is the active ingredient in many insect repellent products. It is used to repel biting pests such as mosquitoes and ticks, including ticks that may carry Lyme disease. Products containing DEET currently are available to the public in a variety of liquids, lotions, sprays, and impregnated materials (e.g., wrist bands). Formulations registered for direct application to human skin contain from 4 to 100% DEET. Except for a few veterinary uses, DEET is registered for use by consumers, and it is not used on food.

DEET is designed for direct application to human skin to repel insects, rather than kill them. After it was developed by the U.S. Army in 1946, DEET was registered for use by the general public in 1957. After completing a comprehensive re-assessment of DEET, EPA concluded that, as long as consumers follow label directions and take proper precautions, insect repellents containing DEET do not present a health concern. Human exposure is expected to be brief, and long-term exposure is not expected. Based on extensive toxicity testing, the Agency believes that the normal use of DEET does not present a health concern to the general population. EPA completed this review and issued its registration decision (called a RED) in 1998.

Biting insects follow the scent of carbon dioxide gas to find a meal. Skin and breath naturally give off a carbon dioxide. By spreading a small amount of DEET on exposed skin and applying it to external clothing, insects cannot readily locate the source of the carbon dioxide. DEET works to repel biting insects, by blocking the receptors on an insect's antennae which help it home in on its host.

What is Permethrin, is it safe and how does it work?

Although known as a repellent, permethrin is actually a contact insecticide. That is, the chemical composition of permethrin is designed to kill insects through contact. Permethrin comes in many forms and has various uses for controlling insects. Not all permethrin is blended for the purpose of bonding to fabric. Most permethrin is agricultural which is for pest control on vegetation. Its design purpose is to stick to plants thus protecting the plants. Veterinary products are designed to adhere to animal skins/hair or premises and are not for fabric application. Some permethrin is formulated for treatment of medical conditions such as head lice and scabies. The formulations are not interchangeable mostly because of solvents utilized.

Permethrin is virtually non-toxic to humans and no systemic effects have been reported. In EPA and FDA tests, it was uncommon to have any skin reddening, rash or other irritation. When used as a repellent, permethrin is applied to exterior clothing where it dries and bonds to the cloth fiber. This water-based formula is non-staining, odorless and has exceptional resistance to degradation by sunlight (UV), heat and water. Although permethrin is approved for skin application under certain circumstances such as head lice formulas, it is not applied to skin as a repellent. Permethrin does not bond to skin (stick) and is quickly deactivated by skin's esterase action into inactive compounds. Because of these attributes permethrin offers no repellent benefit on skin. It is only effective when used as a clothing treatment. The EPA categorizes permethrin as a Category III (Low Toxicity) for oral and skin contact and a Category IV (Very Low) for inhalation and skin irritation.

Permethrin acts on the nervous system of insects. It interferes with the sodium channels to disrupt the functions of the neurons, and causes muscles to spasm, culminating in paralysis and death.

So what is the two barrier system?

The DoD system consists of both permethrin treated clothing and DEET applied to skin. The use of one without the other will undermine the system and increase the risk of insect or tick bite.

Permethrin can be purchase in two forms; aerosol and liquid. In most cases you can purchase the aerosol form at most outdoor sporting stores and at Walmart. I have not seen is told at Target or Kmart. The liquid form can be ordered on the web and I have provided a web address at the end of this article. The aerosol form generally comes in 6 oz cans and generally one can is good for one pair of pants and one shirt. It is applied directly to the clothing until moist and then the cloths are allowed to air dry in a well ventilated area. A single application of permethrin to clothing will generally last several weeks and through several washings. The second form of permethrin is the liquid concentrate. It is usually purchased as a kit which contains the liquid concentrate, protective gloves, and a large plastic bag. The concentrate is mixed with an appropriate amount of water and placed into the large plastic bag. The shirt and pants are then immersed in the mixture and allowed to set for a couple of hours soaking up all of the mixture. The pants and shirt are then allowed to air dry. This type of application can provide protection for up to an entire year or 40-50 washings.

DEET as well comes in many forms; aerosol, liquid, or lotion as well as many concentrates. The higher the concentrate the longer the protection lasts. A concentrate of 5% will provide approximately 90 minutes of protection while a concentrate of 100% will last approximately 10 hours. Most recently a new water based product (normally alcohol is the base) has been developed that shows extraordinary promise of both safety of use and protection realized. Introduced in 1998, is by far the most advanced and effective delivery system available. The active ingredient, DEET, is encapsulated (surrounded) at a 20% concentration within a skin nourishing protein just the way air is captured within a ping pong ball . . . and the system is water based. An application of Controlled Release contains many of these protein ping-pong balls that are suspended in a water-based lotion. After contact with skin, the protein balls begin to breakdown releasing the captured DEET. The process continues as each microscopic ball is depleted then replaced by a new ball that contacts the skin, releases its DEET and so on. The process takes up to 24 hours for one application. The initial application can be adjusted when the user is in an area of more aggressive insects. To adjust simply apply more product during initial application, with no need to reapply during the day. The only commercially available product using this technology is Sawyer Controlled Release.

Because protein's adherence to the skin is so effective, these formulas are very resistant to perspiration (sweat-off), and water. When applied they are dry and comfortable with no greasiness. This system results in very effective protection and is the safest repellent by far. However, it is only effective when used on skin because clothing does not have the capability to release the proteins.

Commercial Products

The commercial version of the military permethrin aerosol is:

Sawyer Tick/Mosquito Aerosol Permethrin Repellent


Coulston Duranon Odorless Tick/Mosquito Repellent


Repel Permanone Clothing Repellent


The commercial version of the military DEET lotion is:

3M UltraThon Lotion



Permethrin- when purchasing permethrin look aerosol that contain a 0.5% permethrin content. A single application at this level should provide protection for approximately 5 washing before requiring reapplication. Products brand names include Repel Permanone, Coulston Duranon, Sawyer Duranon or Permethrin or other brands. Sawyer also makes a commercial version of the military liquid treatment kit for soaking clothing.

DEET- There are currently 147 brand products registered with the EPA and the CDC that contain DEET. Most every supermarket and general merchandise store sells one brand or more. If you are interested in the Sawyer Controlled Release see the web site below.

Sawyer products can be purchased on line from many sources including:

SCS Limited http://www.scs-mall.com/insect-repellents/

REI http://www.rei.com/gear/feature/search/vendor_link/Sawyer

DOM’s Outdoor Outfitters http://domsoutdoor.com/product.asp?pn=1-029007

Sources of Info.

1. Department of Defense Deployment Health and Family Readiness library
2. National Pesticide Information Center