DEET is arguably the most popular bug repellent in the world. Each year, millions of Americans spray it directly on their skin before camping, hiking, and cookouts to repel biting insects like mosquitoes. While DEET has one of the safer reputations among synthetic insecticides, it’s still an artificial chemical, and something we suggest thinking twice about before using around yourself, your family and pets. Here are 7 scary details to consider before you reach for another bottle of DEET-based bug spray.
1. MOSQUITOES ARE ADAPTING TO IT
While some types of mosquitoes are known to have a genetic resistance to DEET-based repellents, it seems now other mosquitoes are developing an immunity, too.
A study examining the host-seeking behavior of mosquitoes found that three hours after an initial exposure some mosquitoes displayed insensitivity to the repellent. Researchers believe this decreased response to DEET after previous exposure indicates that individual mosquitoes can adapt an immunity against the repellent that’s based on something similar to a learned behavior rather than solely genetics.
2. IT'S BEEN LINKED TO SEIZURES
Although infrequent, potentially fatal seizures have been linked with DEET use. In 1998, The Environmental Protection Agency (EPA) pointed to up to 46 cases of possible DEET-related seizures, including, sadly, 4 deaths.
The agency noted “it does appear that some cases are likely related to DEET toxicity,” and also suggested that more seizure cases are probably linked to the repellent but that “physicians may fail to check for history of DEET use or fail to report cases of seizure subsequent to DEET use.”
3. IT CAN INCREASE THE TOXICITY OF OTHER INSECTICIDES
Did you know DEET can actually strengthen the toxicity of other common synthetic pesticides?
Carbamates, a toxic family of insecticides often used in conjunction with DEET, is one such example. One of the studies that looked at DEET’s toxic interaction with carbamate insecticides concluded, "These findings question the safety of DEET, particularly in combination with other chemicals, and they highlight the importance of a multidisciplinary approach to the development of safer insect repellents for use in public health."
4. IT'S NEUROTOXIC TO MAMMALS
It was long believed that DEET simply had an olfactory effect on biting insects like mosquitoes, meaning it repelled them simply by smell. More recent studies, however, have discovered that while DEET does repel by scent, it also deters pests through neurological means.
One such study states “We've found that DEET is not simply a behavior-modifying chemical but also inhibits the activity of a key central nervous system enzyme, acetycholinesterase, in both insects and mammals". Commenting on similar findings, researchers of another study concluded, “These findings indicate that DEET has neurological effects on insects in addition to known olfactory effects, and that its toxicity is strengthened in combination with other insecticides.”
5. IT CAN MELT PLASTIC
If you knew your bug spray could melt plastic, would you still put it on your skin?
In addition to repelling bugs, you might be surprised to learn DEET is a rather powerful solvent, especially when it comes to synthetic materials like plastic. This is especially relevant to outdoor enthusiasts like hikers and campers, as DEET is known to destroy items like camping gear, plastic bottles, sportswear, and more.
6. IT'S TOXIC TO PETS
The ASPCA Animal Poison Control Center states that pets exposed to DEET products can experience “significant clinical” side effects. These health complications include skin irritation, eye damage, and respiratory issues, including airway inflammation and difficulty breathing. Gastrointestinal distress and nervous system problems are also linked to DEET exposure, such as ataxia, disorientation, and seizures.
7. IT'S SAID TO ALTER MOOD AND IMPAIR COGNITIVE FUNCTION
The Pesticide Information Project of Cooperative Extension Offices of Cornell University reports that in the late ‘80s Everglades National Park employees were studied to help determine the possible health consequences associated with prolonged DEET exposure.
It was discovered that those who used DEET more frequently were more likely to suffer negative side effects, including but not limited to insomnia, mood disturbances, impaired cognitive function, nausea, headaches, dizziness, and more.