DEET and picaridin are conventional mosquito repellents registered for use on skin and clothing in many countries worldwide. According to the Centers for Disease Control and Prevention, they are more effective than other insect repellents on the market.
DEET Mosquito Repellent
DEET is an abbreviation for N,N-Diethyl-meta-toluamide, a chemical developed by the United States Army and made available to the general public in the mid-20th century. It is thought to work by interfering with an insect's sensory receptors and hindering its ability to detect chemicals given off by humans and other mammals. When you are wearing DEET mosquito repellent, you are undetectable by nearby biting insects, including mosquitoes, midges, gnats, ticks and sand flies.
DEET is scientifically proven to be effective against biting insects that spread malaria, encephalitis, Lyme disease and other serious diseases. The higher the concentration of DEET a mosquito repellent contains, the longer it provides protection from insect bites before reapplication is necessary. When deciding which concentration to use, consider the length of time you will be outdoors, your risk of being bitten by insects and the prevalence of insect-borne diseases in your area.
According to the Centers for Disease Control and Prevention (CDC), a mosquito repellent containing 23.8 percent DEET may provide about 5 hours of protection against mosquito bites. A product containing 20 percent may give about 4 hours of protection. The duration of protection DEET mosquito repellent provides also depends on other factors such as temperature and water exposure.
DEET is safe for short-term human exposure and is registered for use as an insect repellent with the U.S. Environmental Protection Agency (EPA). People are unlikely to suffer any ill effects if they use a repellent containing around 30 percent DEET. DEET repellent is approved for use on both adults and children and is not expected to present a safety risk as long as it is used according to label directions.
DEET has a long history as a safe and effective insect repellent, but alternative repellents may be more suitable for the following reasons:
- There are reports of DEET sensitivity resulting in skin reactions and eye irritations
- Some people prefer not to put chemicals on their skin and would rather use natural products
- DEET mosquito repellent can have a chemical smell and a greasy feel (although modern repellents are generally more pleasant to use)
- DEET is a solvent and there are reports of it damaging plastics and other man made materials, including glasses, clothing and jewellery
- Some people have concerns about DEET's environmental safety
What is Picaridin?
Picaridin is referred to as Icaridin by the World Health Organization (WHO) and its trade names include Bayrepel and KBR 3023. Picaridin is a colourless, virtually odourless liquid and is present in a range of insect repellent products by Autan, Avon, Care Plus and Cutter.
According to the National Pesticide Information Center, Picaridin works in a similar way to DEET by interfering with insects' olfactory senses and leaving them unable to detect humans. Picaridin provides long-lasting protection against disease-spreading insects including mosquitoes, ticks, biting flies, fleas and chiggers, and is a reliable alternative to DEET.
On account of the fact that scientific testing has proven the effectiveness of picaridin, the CDC recommends picaridin for use as an insect repellent. Furthermore, after close inspection of peer-reviewed, scientific studies, the CDC considers picaridin and DEET to be superior to other insect repellents.
Is Picaridin Safe?
When applied normally as directed, picaridin does not cause irritation to skin, does not pose a health risk to humans, nor is it likely to be carcinogenic. The CDC recommends pregnant women use insect repellents containing DEET or picaridin to reduce the risk of mosquito-transmitted diseases such as West Nile virus. No adverse effects of using picaridin during pregnancy or while breastfeeding have been reported.
Picaridin is also registered with the EPA, meaning that it has been thoroughly assessed for both efficacy and safety. It has low toxicity to mammals, birds and aquatic life, and is unlikely to be harmful to the environment.
There are alternative repellents to DEET and picaridin, such as oil of lemon eucalyptus, IR3535 and citronella. Soybean oil, geranium oil and peppermint oil may also have insect repellent properties, but there is much debate over their efficacy. DEET and picaridin are wise choices if you are vulnerable to attacks from mosquitoes in malarial areas.
CDC: "Insect Repellent Use and Safety".
CDC: "FAQ: Pregnancy & Breastfeeding".
EPA: "New Pesticide Fact Sheet: Picaridin".
EPA: "The Insect Repellent Deet".
National Pesticide Information Center: "Picaridin Technical Fact Sheet".