DEET Insect Repellent
Is it safe to use?
Yes! According to the US Environmental Protection Agency, which conducted a comprehensive re-assessment of DEET in 1998 and an interim review in 2014, "the normal use of DEET does not present a health concern to the general population, including children." Always consult the label instructions on proper use. DEET can, however, deteriorate synthetic materials and fabrics in technical outdoor clothing like rain shells and synthetic shirts, so be sure to only use as directed on exposed skin, not under clothing. DEET is especially effective at repelling mosquitos and ticks that can carry all sorts of nasty diseases. For travelers that could come in contact with mosquitos carrying Zika or West Nile virus, we almost always recommend a DEET-based lotion formula. If you're looking for protection from ticks, combine DEET on exposed skin with Permethrin-treated clothing for the most protection.
Do I need the highest percentage DEET formula possible for the best protection?
Not necessarily. 30-34% DEET is about as effective as it gets. Some formulas, especially sprays, will have a higher percentage to help it last longer. But if you use a lotion, you can get a formula with a much lower percentage, like 20-30%, that will last up to 12 hours, such as 3M's Ultrathon DEET lotion.
For more information on DEET: