Tip of the Week: How to Repel Mosquitoes Safely

Remove any standing water where mosquitoes can breed around your yard, such as plant pots, leaky hoses, clogged gutters, empty buckets, toys, and old tires. Trim back overgrown vegetation, and encourage natural predators like bats, birds, dragonflies, and frogs. Protect yourself from mosquitoes by wearing long-sleeved, loose, light colored clothing. When sitting outside, use an oscillating fan, a screened area, or even a pop-up shelter. Burning citronella candles outside may also help repel mosquitoes. As a last line of defense, employ least-toxic mosquito repellents (but with the understanding that no acceptable repellent will provide complete protection from bites).

Many common mosquito sprays contain harmful ingredients, so it is important to read labels carefully before buying and using repellents.

Least-Toxic Mosquito Repellents:

Although many essential oil insect repellents are registered by the U.S. Environmental Protection Agency (EPA), only the following active ingredients in repellents are evaluated by EPA for health risks and product effectiveness, and also considered least-toxic by Beyond Pesticides. With any repellent, read the directions and follow the label carefully, and be sure to avoid contact with sensitive areas like the eyes and open wounds. These materials are all alternatives to the hazardous ingredient DEET.

Oil of Lemon Eucalyptus (OLE) **Best Choice**
The U.S. Centers for Disease Control and Prevention (CDC) recommends OLE repellents as an effective alternative to DEET. OLE masks both carbon dioxide and lactic acid exhalations that alert mosquitoes to our presence, hiding humans from detection. Only formulated, refined OLE is registered by the agency as a repellent; note that “pure” lemon eucalyptus oil is registered for safety, but not repellent effectiveness by EPA. A synthetic version of the active ingredient in OLE, p-Menthane-3,8-diol, is also on the market, but Beyond Pesticides suggests considering the refined, natural extract. Protection times are similar to DEET-based repellents.

  • Cautions: Do not apply to children less than 3 years of age.
  • Product Examples: Repel Lemon Eucalyptus Insect Repellent, Cutter Lemon Eucalyptus Insect Repellent.
  • Estimated Time of Effectiveness: 3-7 hours in areas with aggressive mosquito populations, up to 12 hours in other areas.

Picaridin (Icaridin, or KBR 3023)
A synthetic version of the piperine compound in pepper, picaridin is a relatively new insect repellent that can be used as a less toxic alternative to DEET. Although there is limited data available on this product, particularly concerning long-term toxicity, evidence does suggest that it has low potential for human harm if used as directed. Picaridin is synthetic, so those seeking a natural repellent should consider OLE.

  • Cautions: Do not apply to children less than 2 months of age.
  • Product Examples: Avon Skin So Soft Bug Guard Plus Picaridin, Sawyer Premium 20% Picaridin Insect Repellent.
  • Estimated Time of Effectiveness: Based on picaridin concentration: 3-6 hours at concentrations below 20%; up to 8 hours at concentrations of 20%.

Insect repellent 3535 is a synthetic repellent that was registered by EPA in 1999, after 20 years of use in Europe, with no reports of adverse effects in the scientific literature. Despite its synthetic make-up, IR3535 is registered as a biochemical pesticide because it is functionally identical to the molecular structure of beta alanine, a naturally occurring amino acid, and the end groups formed through its production are not likely to contribute to toxicity. Still, those looking for a natural repellent should consider OLE.

  • Cautions: Eye irritant, avoid contact in or around eyes.
  • Product examples: Avon Skin So Soft Bug Guard Plus IR 3535 Expedition, Coleman Skin Smart DEET-Free Pump Spray Insect Repellent.
  • Estimated Time of Effectiveness: Based on IR3535 concentration: Around 2 hours at concentrations below 20%; up to 8 hours at concentrations of 20%.