DEET The Real Truth

 http://www.thebumgun.com/how-to-understand-mosquitoes-to-keep-them-away/

We’ve all heard the story… DEET is dangerous! It causes seizures in children! A man by the name of Dr. Mercola heads “the world’s #1 Natural Health Website” and makes the statement, “if this chemical can kill mosquitoes, it can likely do some harm to other life forms too”¹. As it turns out though DEET is actually an insect repellent not an insecticide. It disrupts the mosquito’s ability to sense L-lactic acid, a component of human sweat that mosquitos use as a host-finding cue². DEET has also been shown to be quite safe; it is not an endocrine disruptor, and not a human carcinogen³. No adverse effects are detected when applied to pregnant women in the mother or fetus. The babies also displayed no differences in development or survival rate at birth and age one when compared to women who did not use DEET⁴. DEET is classified as a “low toxin” meaning it is relatively safe and requires very large dosages to cause adverse effects. In fact the dermal LD₅₀ (the amount applied to the skin that will kill 50% of the test subjects) in rabbits is 4280mg/kg⁴. So lets say humans have the same LD₅₀ value  (even though it is probably mush larger). An average woman would have to apply about 5.6 cans of the 230g insect repellent if they were 25% DEET. That is an awful lot of insect repellant! Dr. Mercola’s website suggests a few interesting alternatives to DEET, the best one in my opinion was, “staying indoors from dusk to dawn, the peak mosquito biting hours”¹. As it turns out there are actual alternatives: PMD from lemon eucalyptus (Corymbia citriodora) extract, citronella, neem, natural oils and emulsions, and essential oils⁵. Though the effectiveness of some of them is debated and they all need to be reapplied frequently. As long as applied as per instruction, not ingested, not sprayed in eyes, inhaled, applied to mucus membranes, or applied to wounds, acne or irritated skin then users are largely safe from dangerous side effects³.

Fun Facts? DEET was first developed by the U.S. Army in 1946 to protect military personnel in mosquito infested areas and was then registered for use by the general population in 1957⁴. There are ~400 chemical compounds on your skin that make you more or less attractive to mosquitoes. Things that make you more attractive include, having O type blood, being pregnant and drinking beer⁶!

References:

¹Mercola.com. (2016). The Dangers of DEET & How You Can Safely Repel Mosquitoes Instead.

             Retrieved Nov. 1, 2016, from https://www.mercola.com/article/pesticides/deet.htm

²Vertellus (2016). DEET fact sheet. Retrieved Nov. 5, 2016, from http://www.deet.com/

deetfacts.aspx

³National Institute of Health, U.S. National Library of Medicine. (2016). DEET. Retrieved from

https://toxnet.nlm.nih.gov/cgi-bin/sis/search/r?dbs+hsdb:@term+@rn+@rel+134-62-3 

⁴Jackson, D., Luukinen, B., Buhl, K. & Stone, D. (2008). DEET technical fact sheet. National

Pesticide Information Center, Oregon State University Extension Services. Retrieved Nov. 1, 2016, from http://npic.orst.edu/factsheets/archive/DEETtech.html#prop

⁵ Maia, M. F., & Moore, S. J. (2011). Plant-based insect repellents: a review of their efficacy,

development and testing. Malaria Journal, 10(Suppl 1), S11. http://doi.org/10.1186/1475-2875-10-S1-S11

⁶IFLScience. (2016). Why Mosquitoes seem to bite some people more. Retrieved Nov. 5, 2016,

from http://www.iflscience.com/health-and-medicine/why-mosquitoes-seem-bite-some-people-more/