DEET is also known as N, n-diethyl-m-toluidamide. DEET was first invented during World War II and developed by the U.S. Department of agriculture. It was put into use by the U.S. military in 1946 and registered for public use in the United States in 1957. It has been sold on the market as a personal mosquito repellent since 1965.
Nearly 70 years of research has shown that DEET has repellent effect on a variety of mosquitoes (mosquitoes, flies, fleas, Chigger Mites, midges, etc.) and can effectively prevent mosquito bites. However, it is not effective for bees, Solenopsis invicta, spiders and other self-defense instincts to bite, because they are different from blood sucking arthropods, and they want to stop this extreme behavior unless using insecticides or electric mosquito swatters and other means.
Mechanism Of Action
The mechanism of DEET is still unclear. It was first thought that it could prevent the blood sucking insects from getting close to the human body by playing a deterrent odor.
However, DEET can inhibit the electrophysiological response of mosquitoes to lactic acid and 1-octen-3-ol compounds, mask or block the olfactory system of mosquitoes, and prevent the recognition of suitable prey.
Later, it was found that DEET directly acts on the special olfactory neurons in the antennae of mosquitoes and produces repellent effect, but does not inhibit the perception of lactic acid, CO2 and 1-octen-3-ol.
The latest research also found that the combination of DEET and some molecular targets is the first biochemical reaction to identify external substances, but these findings need to be verified later.
Usage And Precautions
Security
In general, DEET has high safety and low toxicity. Existing studies suggest that DEET has no carcinogenic, teratogenic and developmental effects. The Centers for Disease Control and Prevention (CDC) recommends that pregnant and lactating women use DEET (the same as non pregnant adults) to avoid mosquito bites and reduce the risk of infectious diseases. At the same time, the American Academy of Pediatrics (AAP) recommends that infants over 2 months old use 10% - 30% DEET, which is safe and effective, and should not be used more than once a day. It is not suitable for infants under 2 months old
Effectiveness
The content of DEET in the market ranged from 5% to 99%, and it was found that the repellent effect of 10% to 30% DEET was similar. However, the effective time of DEET at different concentrations was different. 10% can provide about 2 hours of protection time, while 24% can provide up to 5 hours of protection time. In addition, swimming, sweating, wiping and rain can shorten the protection time of DEET. In this case, DEET with higher concentration can be selected.
It should be noted that more than 30% DEET can not significantly increase the protection time, but may appear skin rash, blisters and other skin mucosal irritation symptoms, and may also have potential neurotoxicity.
Post time: 01-06-21