What do we know about diethyltoluamide or DEET? It’s a popular ingredient for insect repellents. With the threat of the Zika virus looming, I think it’s high time to check our options. It’s gotten a pretty bad rep over the last few years as horror stories circulated over the internet saying it is incredibly toxic, causes neurological damage, and even fatalities(!!!). Is this notoriety deserved? Let’s take a closer look.
How does it work?
It’s important to take a look at how DEET stops mosquito bites. The Mercola site I linked to above reasons that if it’s strong enough to kill mosquitoes, then logically it should cause damage to all other living things (particularly humans).
Well, according to the United States Environmental Protection Agency (EPA), “Rather than killing them, DEET works by making it hard for these biting bugs to smell us.” So it camouflages us in a way, making us not smell like delicious food to them. I guess that makes sense. I mean, it is an insect repellent, not an insecticide. The big difference is that insecticides do kill bugs while insect repellents prevent bug bites.
What are the effects of DEET use?
Now this is where things get hairy. According to this article from the Los Angeles Times, ‘The Agency for Toxic Substances and Disease Registry, part of the U.S. Department of Health and Human Services, offers a comprehensive list of studies and case reports on the health effects of DEET. Overall, it concludes: “In the more than 45 years that DEET has been used in the U.S., reports of adverse effects in humans associated with the dermal application of DEET have been relatively rare, given the billions of applications of the repellent.”‘ The articles goes on, saying “From 1961 to 2002, eight deaths from DEET exposure were reported in the medical literature, including three from deliberate ingestion, two from skin exposure and three in female children ages 17 months, 5 years and 6 years, respectively. In the last three cases, “heavy,” “frequent” or “nightly” applications of DEET were reported.”
Conflicting reports come from the National Pesticide Information Center (NPIC), though: “A trial was done on women to test the safety of using DEET to prevent malaria during pregnancy. Women used a product with 20% DEET on their legs and arms each day during their second and third trimesters of pregnancy. DEET crossed the placenta and was found in 8% of the cord blood samples. There was no increase in birth defects or problems with the survival in the young and there were no further problems in the first year of life.”
Sooooo. It appears that adverse effects of DEET usage arise from inappropriate use and the percentage of DEET in the product. It seems that DEET truly is hazardous, if used in unnecessarily large dosages, or ingested inappropriately. I mean, it’s just like medicine: if it’s not taken in the correct dosage and administered improperly, it might do more harm than good.
So how should products with DEET be used?
According to the Center for Disease Control and Prevention, we should always keep the following in mind:
“• Read and follow all directions and precautions on the product label.
• Store DEET out of reach of children.
• To apply to face, first spray product onto hands, then rub onto face.
• Use only when outdoors and wash skin with soap and water after coming indoors.
• Higher concentrations of DEET may have a longer repellent effect, however, concentrations over 50% provide no added protection.
• Use just enough repellent to cover exposed skin and/or clothing. Avoid over-application of the product.
• DEET may be used on adults, children, and infants older than 2 months of age. Protect infants from mosquito bites by using a carrier draped with mosquito netting with an elastic edge for a tight fit.
Be safe with DEET :
• Do not allow children under 10 years of age to apply repellent themselves.
• Do not apply to young children’s hands or around eyes and mouth.
• Do not breathe in, swallow, or get into the eyes (DEET is toxic if swallowed.)
• Do not put repellent on wounds or broken skin.“
The bottom line: would I use it?
Let’s weigh our options.
DEET has proven itself as a very effective insect repellent, masking human scent from biting insects. BUT there have been cases where people have suffered from its use. Even our own Food and Drug Administration (FDA) classifies products with DEET under “registered household hazardous products.” Still, these cases have been relatively rare and are associated with inappropriate dosage and use.
On the other hand, not using an insect repellent makes me more prone to insect bites, particularly the dreaded mosquitoes. A single bite from a carrier mosquito can cause potentially deadly diseases like dengue, malaria, and the Zika virus.
There are other insect repellents available, but according to a study by the New England Journal of Medicine comparing different kinds of insect repellents available in the market, “DEET-based products provided complete protection for the longest duration. Higher concentrations of DEET provided longer-lasting protection. A formulation containing 23.8 percent DEET had a mean complete-protection time of 301.5 minutes. A soybean-oil–based repellent protected against mosquito bites for an average of 94.6 minutes. The IR3535-based repellent protected for an average of 22.9 minutes. All other botanical repellents we tested provided protection for a mean duration of less than 20 minutes. Repellent-impregnated wristbands offered no protection.“
If you’re comfortable reapplying insect repellent every 20 minutes or so, then by all means go for the organic or natural ones. I admit that when all the bad news about DEET erupted, I naturally gravitated to insect repellents proudly advertising that they are “DEET-FREE!!” but now… As a mother (and a pregnant one at that), I can say that I’m comfortable using products with DEET. Now that I know what concentration works best, and how to use them properly, I’m not scared witless anymore. The alternatives carry far more risk to me and my family. Preventing diseases is more important than concerning myself with the possible hazards linked to DEET.
Do you use products with DEET? If not, what do you use to prevent bug bites? I’d love to know! 😉