DEET or diethyltoluamide, is the most common active ingredient in insect and mosquito repellents. DEET was historically believed to work by blocking insect olfactory receptors for a volatile substance that is contained in human sweat and breath.
However DEET bad for humans as well as the mosquitoes we humans are trying to repel. Studies have shown that DEET causes brain cell death and behavioral changes in rats after frequent and prolonged use. This exposure causes neurons to die in regions of the brain that control muscle movement, learning, memory, and concentration. Rats treated with an average human dose of DEET (40 mg/kg body weight) performed far worse when challenged with physical tasks requiring muscle control, strength and coordination.Upto 56% DEET applied topically penetrates human skin. And 17% absorbs into the blood stream. The most serious concerns about DEET are its effects on the central nervous system.DEET may have significantly greater toxicity when combined with ethyl and isopropyl alcohols and freon which are components of some DEET repellents.
How to Avoid DEET and Mosquitoes at the same time?
AVOID DEET based (or any synthetic pesticide based) repellers. Humanity survived millions of years with mosquitoes without DEET and its ugly cousins. Use natural alternatives and preventive methods instead.
Another alternative to DEET is pyrethrin. Pyrethrins are a pesticide created from the chrysanthemum flower. It is generally considered nontoxic
Essentials Oils which act as Natural Mosquito Repellents
There are many essential oils with proven bug repellent powers which have been used for centuries
Lemon Grass Oil
Long Term Deet Exposure is Harmful:http://www.naturalnews.com/001586.html
Symptoms of DEET ingestion ;
https://www.nlm.nih.gov/medlineplus/ency/article/002763.htm (This also has recommendations for what to do if someone does consume a lot of DEET or get it in their eyes.)