Use and Safety of Mosquito Repellents

The June 2008 quarterly Adult and Senior Care Update from California Dept. of Social Services suggests ways to reduce the risk of West Nile Disease. Among those recommendations was “Use an effective mosquito repellent containing ingredients such as DEET, picaridin, or oil of lemon eucalyptus.” This blog contains further information from the Centers for Disease Control and Prevention (CDC) regarding mosquito repellent.

CDC has identified several U.S. Environmental Protection Agency (EPA) registered products containing the following active ingredients that typically provide reasonably long-lasting protection:

  • DEET
  • Picaridin
  • Oil of Lemon Eucalyptus or PMD
  • IR3535 

EPA considers DEET and Picaridin as “conventional repellents” and Oil of Lemon Eucalyptus, PMD, and IR3535 as “biopesticide repellents.” Repellent efficacy and duration of protection vary considerably among products, among mosquito species, ambient temperature, amount of perspiration, exposure to water, and other factors. In general products with <10% active ingredient may offer only limited protection, often 1-2 hours, and may need to be reapplied. Products with concentrations above ~50% do not offer a marked increase in protection time (for example, products containing 23.8% DEET provide an average of 5 hours of protection from mosquito bites). Choose a repellent to provide protection for the amount of time that you will be outdoors. 

Products containing permethrin are to be used on clothing, shoes, etc. and should not be applied directly on the skin. Products containing oil of lemon eucalyptus specifies that they should not be used on children under the age of three years. DEET-based repellents may be used along with a separate sunscreen. No data are available regarding the use of other active repellent ingredients in combination with a sunscreen. 

EPA recommends the following precautions when using insect repellents:

  • Apply repellents only to exposed skin and/or clothing (as directed on the product label.) Do not use repellents under clothing.
  • Never use repellents over cuts, wounds or irritated skin.
  • Do not apply to eyes or mouth, and apply sparingly around ears. When using sprays, do not spray directly on face–spray on hands first and then apply to face.
  • Do not allow children to handle the product. When using on children, apply to your own hands first and then put it on the child. You may not want to apply to children’s hands.
  • Use just enough repellent to cover exposed skin and/or clothing. Heavy application and saturation are generally unnecessary for effectiveness. If biting insects do not respond to a thin film of repellent, then apply a bit more.
  • After returning indoors, wash treated skin with soap and water or bathe. This is particularly important when repellents are used repeatedly in a day or on consecutive days. Also, wash treated clothing before wearing it again. (This precaution may vary with different repellents–check the product label.)
  • If you or your child get a rash or other bad reaction from an insect repellent, stop using the repellent, wash the repellent off with mild soap and water, and call a local poison control center for further guidance [1-800-222-1222]. If you go to a doctor because of the repellent, take the repellent with you to show the doctor. 

Other than those recommendations listed above, EPA does not recommend any additional precautions for using registered repellents on children or on pregnant or lactating women. 

For more information about mosquito repellents and West Nile virus, you may wish to view the following CDC websites:

One Response to “Use and Safety of Mosquito Repellents”

  1. Nice list from EPA for safety and use of mosquito repellent. Mosquito precaution is must for every south countries in this world.

Discussion Area - Leave a Comment