THOUGHTS ON DEET & LYME DISEASE
By Liberty Goodwin, Director, Toxics Information Project (TIP)
Consumer Reports printed an article entitled “Protection at a Price-DEET’S DOWNSIDE”. (July 1993, pg. 453) It points out that: “DEET is readily absorbed into the bloodstream, and medical reports have shown that absorption of DEET sometimes has serious consequences.” Among the most dramatic instances: Six girls under age nine developed toxic encephalopathy, a swelling of the brain that can cause disorientation, convulsions, and death. An ABC PrimeTime Live segment reported the stories of Tim Christiansen, who at 26 years old, died after using DEET twice one summer day in 1994; and of Elijah Harrison, an 8-year-old boy whose mother sprayed him with a 25% DEET product once a day for two days – he still suffers from seizure.
Duke University Medical Center pharmacologist Mohammed Abou-Donia has been doing extensive research on DEET. He says that children in particular are at risk for subtle brain changes caused by chemicals in the environment, because their skin more readily absorbs them, and chemicals more potently affect their developing nervous systems. Commonly used preparations like insecticide-based lice-killing shampoos and insect repellents are assumed to be safe because severe consequences are rare in the medical literature. Yet subtle symptoms — such as muscle weakness, fatigue or memory lapses — might be attributed erroneously to other causes, according to Abou-Donia.
On the Safe2use website, Patricia Taylor brings up another concern – that senior citizens using higher dosage applications of DEET should also be specifically precautioned about misuse. They should especially be told to use DEET sparingly only on exposed skin and to not use DEET underneath clothing. A senior citizen being brought into an emergency room suffering from incoherence, altered behavior, headache, restlessness, irritability, ataxia, rapid loss of consciousness, hypotension or seizures will not necessarily be screened for pesticide poisoning, but rather for other, more common, conditions to the elderly. Seniors with chronic skin conditions should be extremely cautious about applying DEET to their skin. DEET can exacerbate certain skin conditions and enters the body more quickly through wounds, where it is more toxic in the gut and eventually excreted through the kidneys. Ms. Taylor also questions the high dosage of DEET in some products as being too toxic for this age group.
The point has been made that short-term applications, especially of the lower-strength DEET formulas, do not appear to cause reactions in many people. However, it is my observation that our society tends to minimize or miss the long-term, chronic effects of many chemicals. Over and over, substances thought to be safe are later banned when evidence of their toxicity is finally unavoidable. Years ago, the “safety” of DDT was loudly proclaimed. The popular pesticide Dursban was recently forced off the market after years of use, because of health concerns.
In addition, research tends to focus on immediate, acute reactions, and examines only individual chemicals, though synergistic effects between multiple substances can be significant. Research is often done by persons with connections to the industry producing a product, raising questions of possible bias. Moreover, it is not unheard of for findings to be stifled, and scientists to find their careers impeded by over-zealous attention to unwelcome results. Product safety is at best an uncertain thing.
CONCERNS ABOUT LYME DISEASE
Lyme Disease is an infection that causes an inflammatory disease affecting the skin, joints, nervous system, and other organ systems. Symptoms usually appear within a week or two of infection but may develop up to 30 days after the tick bite – or not at all. The symptoms of early Lyme disease may include a red-ringed bull’s-eye rash which appears either as a solid red expanding rash or blotch, or as a central red spot surrounded by clear skin that is ringed by an expanding red rash.
The rash persists for as much as 3 to 5 weeks. It may be warm to the touch and is usually not painful or itchy. Other early localized signs include: Swelling of lymph glands near the tick bite, fatigue, headache, achiness, joint pain , chills. More serious symptoms, even death, may follow.
WHAT ARE THE ALTERNATIVES TO DEET?
There are a variety of natural insect repellents, including Bite Blocker , Buzz Away, Herbal Armor, Jungle Juice, Natrapel, citronella or lavender oil, catnip oil (avoid felines while using this one), rosemary, pennyroyal, lemongrass and cedarwood. Some have proved very effective when tested in comparison with DEET – but with a caveat. The major advantage of DEET seems to be its lasting power. For example, a 7 % DEET formula (relatively low strength) might provide two hours protection, whereas the citronella (5-10 %) or lavender oil only about 30-60 minutes. At this time, TIP has insufficient information to recommend any one product. However, there is some research indicating that Bite Blocker may be competitive with DEET in protection time. Watch the TIP Web Site for links and updates – and tell us what works for you.
What then to do? There is some comforting news. First, ticks are unlikely to be found on well-mowed grass. Second, the first line of defense according to most experts is avoidance. This would include covering up, tucking jeans into socks, staying in the center of the path while walking, avoiding tall grass, not sitting on the ground. It’s also good to know that, according to kidshealth.org/Nemours Foundation, your child’s risk of developing Lyme disease after being bitten by a tick is only 1.4%. To be safe, though, you’ll want to remove the tick as soon as possible because risk of infection increases between 24 to 72 hours after the tick attaches to the skin. This is a very important point. According to the CDC (Center for Disease Control), “The transmission of B. burgdorferi (the bacteria that causes Lyme disease) from an infected tick is unlikely to occur before 36 hours of tick attachment. For this reason, daily checks for ticks and promptly removing any attached tick that you find will help prevent infection.” The American Academy of Pediatrics says that transmission of the bacteria that causes Lyme “usually requires a prolonged duration of attachment (> 48 hours). Of course, there is no guarantee of safety– I have heard a few reports of earlier infection.
Finding the ticks may be enhanced by wearing light colored clothing and by examining your skin in the shower after returning from an excursion. Embedded ticks should be removed using fine-tipped tweezers. DO NOT use petroleum jelly, a hot match, nail polish, or other products. Grasp the tick firmly and as closely to the skin as possible. With a steady motion, pull the tick’s body away from the skin. The tick’s mouthparts may remain in the skin, but do not be alarmed. The bacteria that cause Lyme disease are contained in the tick’s midgut or salivary glands. Cleanse the area with an antiseptic.” If you must remove the tick with your fingers, use a tissue or leaf to avoid contact with infected tick fluids. Do not prick, crush or burn the tick, as it may release infected fluids or tissue.
TIP’s present thinking about the DEET question is to use non-DEET alternative repellents, (preferably fragrance-free) – and apply them more often if needed. Always check carefully for any ticks after possible exposure. It is probably unnecessary to apply insect repellent vs. ticks unless either entering a wooded or long grass area. If you feel you must use DEET, use a product with the smallest percentage of it that seems effective. Read labels carefully. “DEET should be applied sparingly, according to product label instructions, only to exposed skin, and not to a child’s face, hands, or skin that is irritated or abraded. After the child returns indoors, treated skin should be washed with soap and water,” advises the American Academy of Pediatrics. Both the CDC and the AAP have issued cautions against any use of DEET on children under 3 years old. This is because DEET enters the bloodstream through the skin (and can even pierce fabrics) and children seem especially susceptible to DEET-related problems.