Toxic Free News

The deal is this: DEET is the most common pesticide in personal insect repellents, and it is quite effective at repelling ticks, mosquitoes and other bugs. DEET is also toxic to the human nervous system, and because DEET is applied directly to your skin, your personal exposure to it can be quite high. It can absorb through your skin into your blood stream, and it’s also easy to inadvertently breathe it in, ingest small amounts of it, or get it in your eyes. For all these reasons, Toxic Free NC recommends a very cautious approach to insect repellents.

Some medical sources, including the Centers for Disease Control, believe that the benefits of DEET outweigh the risks, and therefore recommend it for use in people over the age of 2 months old. The American Academy of Pediatrics recommends using formulations with 30% DEET or less (1).

Toxic Free NC takes a much more conservative approach, because effective alternatives carry fewer risks, and are readily available. Medical research has connected DEET with neurological symptoms in people who use it, and poison control calls about DEET back this up: the most commonly-reported symptoms include dizziness and headache, along with skin and eye irritation. More serious symptoms are reported more rarely, including seizures and changes in heart rate. (2) DEET in combination with other chemicals has been implicated in Gulf War Syndrome – a mysterious collection of neurological symptoms reported by thousands of veterans of that war, who were regularly exposed to DEET in combination with other toxic chemicals during their deployments (3). In studies with animals, DEET has been connected with many adverse health effects like damage to DNA (4), miscarriage (5), birth defects (6), problems with sperm (7) and testes (8), and damage to the brain (9).

For these reasons, Toxic Free NC recommends using safer alternatives to DEET for your day-to-day needs - and of course avoiding bites in the first place whenever you can! Here’s my personal strategy for least-toxic bug bite avoidance:

Cover up. Bugs can’t really bite you through your clothing, so when in doubt your best option is to cover up. Dusk and daybreak are when mosquitoes are on the prowl, so consider throwing on a light long-sleeved shirt and switching to long pants when you’ll be outside at those times.

Dork socks. Wearing long pants tucked into light-colored socks really helps for moderate tick-risk activities like yard work or hiking, since ticks most often crawl up your legs – yuck. This also helps for mosquitoes, who I find love to bite my ankles. I know it’s hot and dorky looking, and everyone is rolling their eyes at me right now and thinking “do you really expect me to wear long pants and socks in North Carolina in the summer?” My answer: it works really well, so if you're going outside in an area where you know there's a lot of bugs, and if the bugs bother you more than dork socks do, then yes!

Blow them away. For cookouts, outdoor parties and dinners on the patio, one great way to keep mosquitoes and other biting flying insects away is with a big fan. A stiff breeze is always welcome on a summer night, so your guests will thank you!

Tick Checks. Repellent or no, make a regular practice of “tick checks” when you’ve been out in tick-prone areas. Once a tick has bitten, it takes at least 6 hours, and in many cases 24 hours or more to transmit disease (10). That means you have some time to find and remove them before they do any real harm. Check yourself over for “moving freckles,” as my mom used to call them, using a hand mirror for spots you can’t easily see. You may even consider using a magnifying glass, since some tick species are so small – deer ticks are about the size of a sesame seed. Pay special attention to areas of the body with hair, and/or where clothes rest tightly against the skin, because that is where ticks tend stop on their journey up your body: waist, groin, armpits, bra wire and strap areas, nape of the neck and scalp. Don’t forget to check between your toes and in your belly button!

Herbal Repellents. For everyday activities, such as playing outside and evening cookouts, herbal insect repellents can be quite effective against mosquitoes and ticks, though they need to be reapplied somewhat more often than repellents containing DEET. They work because insects hate the smell, so when the smell fades, it’s time to reapply. Experiment with different herbal insect repellent products on the market, or mix your own (see our recipe!). Keep an eye on the labels for these products as well, since some marketing can be sneaky – read the label carefully and be sure that formula contains only natural oils, and not the pesticides you are trying to avoid. Be mindful also that though herbal oils are natural, they’re strong, so test the herbal repellent first on a small area before general use, especially if you have sensitive skin. Also, know that many herbal products are not recommended for women who are pregnant or nursing. Pregnant or nursing mothers should consult with their doctor before choosing any type of insect repellent, even those that are “natural.” No matter what repellent you choose, you should always wash your hands immediately after applying the repellent, and wash it all off as soon as you come inside.

DEET on Clothes. If the steps above aren’t working, or if you’re headed out to the deep woods for a few days and you’re not sure what you’ll encounter, you might consider bringing along a product containing DEET (check www.cosmeticsdatabase.com for products with a relatively good safety rating). Apply it to the outside of your clothing, especially shoes and pant legs. You’ll get much of the repellent benefits without absorbing quite so much of the chemical through your skin. Be sure to wash these clothes separately from the rest of your family’s laundry.

DEET on you - use with caution! The benefits of applying DEET to your skin may outweigh the risks for very high-risk activities. For example, after a hurricane mosquito levels tend to jump dramatically, just at the time when workers need to be outside for long hours making repairs, thus increasing their risk of exposure to mosquito-borne illness. In these and other high-risk cases, you should choose a least-toxic DEET product, use it carefully according to label instructions, and use as little as will get the job done. Bathe promptly once the activity is over to get the chemical off your skin, and definitely don’t leave it on overnight (unless you’re sleeping in a brush pile!).

A special note on insect repellent products to avoid: Don’t use products that combine DEET and sunblock; sunblock needs to be reapplied more often than DEET, so you’ll wind up putting more DEET on yourself than you should. Toxic Free NC recommends against using clothing treated with insect repellents, and you should definitely never use DEET while wearing insect-repellent clothing. The fabric is impregnated with permethrin, a pesticide which has been connected with increased risk for some health problems, and which has also been shown to act synergistically with DEET to raise health risks when the two are combined (11).

Be smart about insect repellents this summer, and you'll avoid bug bites without dousing yourself in toxic chemicals!

1) ATSDR ToxFAQs: DEET http://www.atsdr.cdc.gov/toxfaqs/TF.asp?id=1035&tid=201

2) Bell, J.W., J.C. Veltri, and Brent C. 2002. Human exposures to N,N-diethyl-m-toluamide insect repellents reported to the American Association of Poison Control Centers 1993-1997. Intern. J. Toxicol. 21:341-352. http://www.ncbi.nlm.nih.gov/pubmed/12396679

3) Abou-Donia, Mohamed, 1996. NEUROTOXICITY RESULTING FROM COEXPOSURE TO PYRIDOSTIGMINE BROMIDE, DEET, AND PERMETHRIN: IMPLICATIONS OF GULF WAR CHEMICAL EXPOSURES. Journal of Toxicology and Environmental Health, Part A, Volume 48, Issue 1 May 1996, pages 35 – 56. http://www.informaworld.com/smpp/6561327-12280280/content~db=all~content=a713850935

4) Abu-Qare, A. and M. Abou-Donia. 2000. Increased 8-hydroxy-2’-deoxyguanosine, a biomarker of oxidative DNA damage in rat urine following a single dermal dose of DEET (N,N-diethyl-m-toluamide), and permethrin, alone and in combination. Toxicol. Lett. 117:151-160. http://www.ncbi.nlm.nih.gov/pubmed/11087981

5) World Health Organization. Undated. Data sheet on pesticides. No. 80. DEET. http://www.inchem.org/documents/pds/pds/pest80_e.htm

6) California EPA. Dept. of Pesticide Regulation. Medical Toxicology Branch. 1999. Summary of toxicology data: DEET. http://www.cdpr.ca.gov/docs/toxsums/toxsumlist.htm.

7) World Health Organization. Undated. Ibid.

8) U.S. EPA. Prevention, Pesticides and Toxic Substances. 1998. Reregistration eligibility decision (RED): DEET. http://cfpub.epa.gov/oppref/rereg/ status.cfm?show=rereg. Pp. 9.

9) Abdel-Rahman, A., A.K. Shetty, and M.B. Abou-Donia, 2001. Subchronic dermal application of N.N-diethyl-m-toluamide (DEET) and permethrin to adult rats, alone or in combination, cause diffuse neuronal cell death and cytoskeletal abnormalities in the cerebral cortex and the hippocampus, and Purkinje neuron loss in the cerebellum. Exp. Neurol. 172:153-171. http://www.ncbi.nlm.nih.gov/pubmed/11681848

10) Dr. David Walker, Univ. of Texas, Galveston, Infectious Diseases, on The People's Pharmacy radio show. Chapel Hill: WUNC Radio. Program number 722. Aired July 3, 2010.
http://www.peoplespharmacy.com/2010/07/03/722-tick-borne/

11) Abu-Qare, A.W. and MB. Abou-Donia. 2003. Combined exposure to DEET (N.N-diethyl-m-toluamide) and permethirn: pharmokinetics and toxicological effects. J. Toxicol. Environ. Health, Pt. B 6:41-53. http://www.ncbi.nlm.nih.gov/pubmed/12587253

Toxic Free News is a publication of
Toxic Free NC
206 New Bern Place, Raleigh, NC 27601
(919) 833-5333, Toll-free 1-877-NO-SPRAY
, http://www.toxicfreenc.org

Mission: Toxic Free NC advocates for alternatives to toxic pesticides in North Carolina by empowering people to make sound decisions about their health and environment.

Staff: Ana Duncan Pardo, Communications Coordinator; Billie Karel, Program Director; Fawn Pattison, Executive Director; Ileana Rodriguez, Administrative Associate.

Interns: Michael Marion, YouTube Outreach Coordinator; Kathryn Newman, Farm to Childcare Intern; Hannah Silver, LoveBug Intern; April Simon, Farm Worker Documentary Intern; Melissa Tosiano, Pesticide Researcher Intern; Laura Valencia, Women without Borders Intern.

Board of Directors: Colleen Boudreau, Treasurer; Juan Echeverria; Ghassan Hamra; Laxmi Haynes; Mindy Hiteshue; Cathy Jones; Michelle Nowlin, President; Annie O'Leary; Katherine M. Shea, Immediate Past President; Allen Spalt.
Emeritus Board Members: Billie Rogers, Jane Sharp MacRae, Erick Umstead.

Community Leadership Council: Melissa Bailey, Myriam Hudson, Mary James, Silvia Peterson.

What’s the deal with insect repellents? by Billie Karel Translated by Francisco Cabral, vea el artículo en español

What’s the deal with insect repellents?
by Billie Karel
Translated by Francisco Cabral, vea el artículo en español