Post by Steve King (Admin) on Jul 23, 2004 15:12:31 GMT -6
There are a variety of chemicals used to repel insects. Some are extracts from plants but the most effective ones are synthetics. Below is a list of your choices:
DEET is the most effective repellent against mosquitoes and ticks.
R-326 is the most effective insect repellent against flies, gnats, and no-see-ums.
Permethrin kills ticks or other insects when it comes in contact with them. It is used on clothing and materials.
GK-264 is both a mosquito repellent and a synergist.
Essential Oils are compounds which occur in nature and may provide a short period of repellency against insects.
These active ingredients are explained in greater detail below:
DEET (N, N-Diethyl-3-Methylbenzamide)
Formerly known as N,N-diethyl-m-Toluamide, Deet is by far the most commonly used insect repellent in the world. This is because it is the most effective repellent against mosquitoes and ticks. After researching hundreds of compounds, Deet was selected by the USDA and the U.S. military as the most economical and safest compound to use. After more than forty years of worldwide use, Deet has a remarkable safety record.
Recent adverse publicity has left many people confused and concerned about the safety of deet. Deet is a skin irritant but does not create a skin sensitivity. This means that after a period of frequent use your skin may become red, even sore to the touch, irritated by the presence of deet. You do not however develop an allergic resistance to deet. If allowed time to recover, your skin will accept the presence of deet again without rapidly developing a rash. Continued use could again develop irritation. The term sensitivity would refer to a condition where your skin develops a resistance to the presence of a chemical and an allergic reaction takes place if that chemical is presented to the skin. Deet has been well studied and does not cause people to develop a resistance to it. People do not develop allergic reaction or skin sensitivity to deet. The amount of deet which can be used prior to developing skin irritation varies from person to person.
Some segments of the medical community have recently expressed concern over the amount of deet absorbed by the skin, especially in children. To date absorption studies relating to deet indicate that the body releases the deet which it absorbs. It is not something which can be defined exactly. However literally billions of applications of deet occur annually, and deet has been in widespread use since 1954. There are no studies or clinical observations to suggest long term dangers of deet when used properly and in accordance with label directions.
R-326 (Di-n-propyl Isocinchomeronate)[/u]
R-326 is the most effective insect repellent against flies, gnats, no-see-ums, and similar pesky insects. R-326 is far more effective than deet against these insects and R-326 only needs to be present in small quantities. Because the molecules are much larger than deet molecules they are absorbed less, and when used in formulations with deet, they even lower the deet absorption rate by blocking access to the skin.
Permethrin
Permethrin is a contact insecticide. That is, it kills ticks or other insects when it comes in contact with them. It is used on clothing and materials. Though harmless to the skin, skin contact de-activates permethrin within fifteen minutes. As a clothing, tent or sleeping bag application, permethrin is very effective at keeping ticks from attaching to you and at reducing the mosquito population in your camping area. Aerosol spray applications of permethrin can remain effective up to six weeks of exposure to light or oxygen, and through several washings.
MGK-264 (N-octyl bicycloheptene dicarboximide)
MGK-264 is both a mosquito repellent and a synergist. As a synergist, or potentiator, MGK-264 both repels mosquitoes and helps the deet to do an even better job of repelling mosquitoes than it would by itself. The MGK-264 molecule is much larger than the deet molecule in size and thus less is absorbed into the skin.
DEET + R-326 + MGK-264 = COMPOSITE or BROAD SPECTRUM
Add these three active ingredients together and you get what we call a Broad Spectrum insect repellent. You get the effective mosquito and tick repellency of Deet and MGK-264, but you also get effective repellency of flies, gnats, no-see-ums, and such because of the R-326. By working together they each become more effective, last longer, and absorb less into the skin than straight deet formulas. A simple rule is to look for three names you cannot pronounce on the label and not just one.
ESSENTIAL OILS
Many compounds which occur in nature provide a short period of repellency against insects. There are well over 150 natural repellents but the more commonly used ones are Citronella, Eucalyptus, Lemon Leaves, Peppermint, Lavender, Cedar Oil, Canola, Rosemary, Pennyroyal, and Cajeput. Essential oils are used primarily by persons concerned about exposure to deet. Generally the EPA considers these oils safe to use in low percentages but overall their effectiveness is usually limited to less than 30 minutes.
Kids and Deet:
Obviously, the EPA has expressed concern about children's Deet absorption through use of sprays which dilute Deet with alcohol. Sawyer Products™ is glad to see the EPA raise this issue, and take such action. In addition to the concerns cited by the EPA, pediatricians voice concern that because a child has twice the area of skin in proportion to their body weight as an adult, a child's system is potentially open to greater absorption and stress than adults. Clearly more studies need to be done to understand the risk. In the meantime, A controlled release lotion offers the best current solution to parents' concerns.
Warning:
Beware of formulas that are not registered with the EPA. Some unregistered repellents have dangerously high concentrations of essential oils and, though somewhat effective against insects, may irritate the skin and cause other side effects. The EPA does not approve any repellent containing more than 10% essential oils and requires registration of any formula with over 3% essential oils. At high concentrations, these essential oils may not be safe.
** My opinion, a good sunscreen/insect repellant 2-in-1 for kids is Off Skintastic. It has 30 SPF and 9.5% DEET. I even use it myself when floating the rivers.
Source: SawyerProducts.com
