DEET - What is DEET and is it Safe?
DEET is an ingredient in many pest control products. But what is DEET? Is it safe? Some people swear by it. Others fear it and say it is toxic, causes reactions and is toxic enough to melt plastic. Is DEET considered safe pesticides? Here is a deeper dive into DEET so you can make informed choices.
DEET is a man-made chemical (N,N-diethyl-meta-toluamide) that was developed by the U.S. Army in 1946. Products containing DEET are available in liquid, lotion, sprays, and impregnated materials such as wristbands. The formulations for use on human skin range from 4% to 100% DEET and the Environmental Protection Agency (EPA) has registered more than 200 products containing DEET. DEET products are also for use on clothing.
Per the EPA, the use of DEET containing products is safe if the label directions are followed and ALL registered pesticides containing DEET have the following directions:
· Do not apply over cuts, wounds, or irritated skin.
· Do not apply to hands or near eyes and mouth of young children.
· Do not allow young children to apply this product.
· Use just enough repellent to cover exposed skin and/or clothing.
· Do not use under clothing.
· Avoid over-application of this product.
· After returning indoors, wash treated skin with soap and water.
· Wash treated clothing before wearing it again.
· Use of this product may cause skin reactions in rare cases.
The following additional statements will appear on the labels of all aerosol and pump spray formulation labels:
· Do not spray in enclosed areas.
· To apply to face, spray on hands first and then rub on face. Do not spray directly onto face.
· DEET is approved for use on children with no age restriction or concentration restrictions.
· If you suspect that you or your child is having an adverse reaction to a DEET product, discontinue use of the product, wash treated skin, and call your local poison control center or physician for help. If you go to a doctor, take the repellent container with you.
The American Academy of Pediatrics states the following additional guidelines for using DEET products on children which are more stringent:
· Do not use on children under 2 months of age.
· Do not use a product that combines DEET with sunscreen as repeated applications may increase the potential toxic effect of DEET.
· Apply sparingly using the lowest concentration effective.
· Do not use DEET near food.
The National Pesticide Information Center states that Scientists do not know exactly how DEET works on all insects. Human exposure to DEET can cause the following:
· Eye irritation, pain and watering
· Skin irritation, redness, rash and swelling
· Stomach upset, nausea and vomiting
· Rare instances of seizures
· DEET use on Pets has shown vomiting, shaking, excitement, lack of coordination and seizures.
Per the Agency for Toxic Substances and Disease Registry (ATSDR), the mode of operation is that DEET affects the nervous systems of pests. If DEET is applied to skin and/or clothing then the person swims in water - the ocean, a lake, stream or waterway, the DEET will wash into the water. The DEET does not evaporate from the water but is eventually consumed by microorganisms. The half life of DEET in water is approximately 4 weeks meaning ½ of the DEET will be gone in 4 weeks, another ¼ of the DEET after 8 weeks, 1/8 after 12 weeks, etc. DEET can be absorbed from contaminated water.
Adverse reactions to DEET are based on many factors including how much you are exposed to (dose), how long you are exposed (duration), and how you are exposed (route of exposure). The most important route of exposure to the general population is through dermal contact from intentional application to human skin and clothing of consumer products containing DEET.
In your body, most of the DEET is broken down into other substances (metabolites) in the liver, and both DEET and the metabolites distribute widely throughout your body. Studies have detected DEET or its metabolites in many organs of exposed animals, including the brain, liver, kidneys, lungs, spleen, fat, tears, and inside the nose.
There have been reports over the last several decades of an association between excessive use of repellents containing DEET and adverse neurological effects including seizures, uncoordinated movements, agitation, aggressive behavior, low blood pressure, and skin irritation.
There were more than 9,000 DEET exposure cases reported to Poison Control Centers between 1985 and 1989 of which 12% required treatment in a healthcare facility. Between 1993 and 1997, there were 20,764 cases of DEET exposure of which 11% required care in a healthcare facility. A study of workers at a national park who used insect repellents or lotions containing DEET repeatedly during the summer season complained more often of chest pain or wheezing, muscle cramping, skin rashes and blisters, dizziness, disorientation, and difficulty concentrating than workers who used the products less often or did not use them at all.
In summary, DEET is a man-made, synthetic chemical that does not exist in Nature. It is a neuro-toxin, meaning it affects the nervous system of pests. The DEET exposure cases reported to Poison Control Centers cited above also affected the nervous systems of humans who were exposed to DEET.