(Beyond Pesticides, July 18, 2014) After years of struggling to combat the rise of Lyme disease in the region, Loudoun County, Virginia has decided to forgo the spraying of a hazardous pesticide in public parks in favor of public education and continued surveillance of park lands. Controversy over spraying arose back in 2012 when Loudoun began ramping its spray program to manage ticks, often the carrier of the disease. Loudon County used the pesticide Talstar, which contains the active ingredient bifenthrin, a neurotoxic chemical whose use raises public health and product efficacy concerns, as documented by the Centers for Disease Control and Prevention.
Beekeepers expressed concern that spraying would greatly damage their bee colonies, as bifenthrin is highly toxic to bees, while conservationists were concerned with the chemicals leaching into waterways and killing aquatic life. At the same time, some researchers point out that there was no evidence that spraying the chemical would reduce the number of Lyme disease infections.
After years of debate and data analysis, David Goodfriend, M.D., M.P.H, director of the Loudoun County Health Department, said that the county’s Lyme Disease Commission’s recommendation was to not spray any of the properties. The recommendation was based on two years of surveillance data at six highly used county parks. Dr. Goodfriend added that the Loudoun Board of Supervisors agreed with the recommendation.
The surveillance data, collected in 2013 and again this year, tracked tick populations over a six-week period. “One of the things that we looked for is to see if there was a time when the nymphs really start coming out in force, because if spraying is going to be done, that’s the best time to do it,” Dr. Goodfriend said. “But there were not that many black-legged ticks in the park —only about 1 percent of the ticks found were black-legged ticks— and of those, there were few nymphs.” Researchers are especially interested in the number of nymph, or juvenile, black-legged ticks, because they are primarily responsible for Lyme infections, Dr. Goodfriend explained. Health officials say that adult black-legged ticks are more easily spotted and removed before an infection can be transmitted.
Loudoun has one of the highest rates of Lyme disease infections in the country and the highest in Virginia, according to health officials. Every year, more than 200 cases are reported, but officials say that the number of infections is probably much higher since many cases are likely to go unreported or undiagnosed.
In response to growing public concern over Lyme disease, the Board of Supervisors declared 2012 “Lyme Disease Awareness Year” in Loudoun and established the county Lyme Disease Commission to implement a 10-point action plan to fight the spread of the disease. This year, the Lyme Disease Commission requested $41,500 in county funding and $27,000 for research surrounding tick populations in the five county parks, as well as $3,000 to spray insecticide in them. The funds that were set aside for the spraying of Talstar will not be spent this year.
The decision to not spray in public parks was welcomed by officials with the Loudoun Wildlife Conservancy, which issued a position paper this past February entitled “Rebalancing Loudoun’s Approach to Lyme Disease Mitigation.” The paper cited research that cast doubt on the efficacy of spraying for ticks and reduction in the rate of Lyme disease infection.
“We called on the county to emphasize data collection, education, and communication in their action plan,” said Alysoun Mahoney, who is the conservation advocacy chair for the conservancy. “We are very pleased that in its July 8 meeting, the statement by [the supervisors’ government services and operations committee] is to a great degree consistent with our recommendations. We think that they’re going in the right direction.”
As an alternative to spraying, county officials and environmental activists underscore the importance of personal prevention measures, such as wearing long, light-colored attire, applying tick repellent, and checking for ticks after being outdoors. Dr. Goodfriend said the county Health Department asks that residents consider a variety of methods to prevent infection, including the management of private property. “Ticks don’t like well-mowed lawns. There are additional ways to keep ticks away —by getting rid of rodent populations and making our properties less conducive to ticks.” In the meantime, the commission will continue to focus its efforts on community education and outreach, and will also spend the summer reviewing tick surveillance data in greater detail “to see what makes the most sense for parks in the future,” Dr. Goodfriend said.
Bifenthrin is identified as an endocrine disruptor by the European Union, and is considered a possible carcinogen by the U.S Environmental Protection Agency (EPA). It is a pyrethroid class pesticide, a group of known neurotoxic chemicals. A study in the journal Environmental Health Perspectives (2007) of infants born to women with agricultural exposure shows a possible impact of bifenthrin on the occurrence of autism spectrum disorders. Bifenthrin is also toxic to birds, fish, and bees.
Not only has bifenthrin been shown to be a highly toxic pesticide, it has been shown to be ineffective in curbing tick populations as well. In fact, a study released by the Centers for Disease Control and Prevention (CDC) in August of last year found that spraying lawns with the insecticide did not reduce the incidence of tick-borne diseases. Despite this, the CDC website still recommends pesticide spraying of yards for protection against tick transmission of Lyme disease. The study was conducted over two years and found that yards that were sprayed with bifenthrin, while seeing a 60 percent reduction in ticks on their property, still had similar levels of tick encounters and tick-borne illnesses. The findings suggest that using pesticides is not an effective way to reduce tick-borne diseases and can instead leave families with negative health effects resulting from the use of toxic pesticides.
There are many alternative ways of reducing one’s exposure to ticks. One effective way to avoid them is to only use unscented deodorant, soap, and shampoo. An exception is Packers Tar Soap, which has a natural pine scent that can keep ticks from biting once they have been picked up. Similarly, you can try using least-toxic herbal repellents such as oil of lemon eucalyptus and essential oils. Most importantly, after walking through high grass in a tick-infested area, check the entire body for ticks, remove ticks, and shower to wash off any ticks that have not yet become embedded. If you do find an embedded tick, remove it carefully. Protect your hands with gloves or a tissue. Use blunt, curved tweezers, not your bare fingers, and exert pressure on the head of the tick and gently pulling the tick straight out very slowly. Do not twist and do not crush the tick. The body fluids can cause infection if exposed to even unbroken skin. Do not kill the tick while still embedded. Kill the tick in soapy water or alcohol, clean the wound with antiseptic, and monitor carefully for any signs of infection. If you observe symptoms of Lyme disease such as a bull’s-eye rash near the bite, consult a physician.
For more information on alternative pest management, please visit Beyond Pesticides’alternative factsheets page.
Source: Washington Post
All unattributed positions and opinions in this piece are those of Beyond Pesticides