(Beyond Pesticides, May 31, 2012) The Centers for Disease Control and Prevention (CDC) and the Maryland Department of Health and Mental Hygiene have enrolled Maryland households in a study that involves spraying the controversial pesticide bifenthrinon their property to determine the efficacy of this approach in controlling Lyme disease. Now in the beginning of its second year, the study found no evidence in the first year that the spraying works to reduce the transmission of Lyme disease. Beyond Pesticides is concerned that study participants have not been provided complete information about bifenthrin’s potential health risks to people.
According to the Baltimore Sun, the study is an effort to find new ways to combat the disease, which infected 1,600 people in Maryland in 2010. Half of the 185 families that have volunteered for the study will have water sprayed on their lawns to serve as a control group, while the other half will receive the bifenthrin treatment. The 185 families that have signed up so far this year get a $25 gift card, lowered from $40 given to the 440 participants last year.
Last year, while the pesticide reduced the amount of ticks on treated lawns compared to the control group, there was a negligible difference in both the numbers of ticks that volunteers reported on their bodies and the number of Lyme disease cases. State officials have declared that they will not advise residents to use pesticides to combat Lyme disease if this second year of testing shows similar inconclusive results in the number of tick bites and Lyme disease cases between the two groups.
Beyond Pesticides believes that it is wrong to put Maryland families at risk of pesticide exposure, especially since the study proved ineffective in its first year. Beyond Pesticides has spoken directly with state health officials in an effort to relate concerns about this study. “It’s improper to be conducting a human experiment like this,” said Jay Feldman, executive director of Beyond Pesticides.
Bifenthrin is identified as an endocrine disruptor by the European Union in May 2010, 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 recent 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. EPA studies with rodents test subjects have led the organization to classify bifenthrin as a possible carcinogen due to the increase of bladder, kidney, and lung tumors in mice exposed to the substance. Further, EPA studies have associated bifenthrin with developmental/reproductive effects, and an increased risk of ovulatory dysfunction in females. See Beyond Pesticides’ action alert on EPA’s proposal to expand the use of these pesticides.
The CDC website and informed consent form do not elucidate the hazards posed by this pesticide.
It reads, “If a person (including a young child or a pregnant woman) or animal were to swallow breathe or touch the chemical, the individual or animal is not likely to become ill. If the chemical comes into contact with the skin or eyes before it has dried, some individuals may have short term irritation that will likely disappear within 12 hours. There are no studies that indicate bifenthrin exposure risks in humans are increased for children or women who are pregnant. At the beginning of the study, you will receive a bifenthrin product information sheet about how to clean skin, flush eyes, and if you should seek medical attention for yourself or pets in case this occurs.”
Beyond Pesticides has stated that it is misleading for the CDC to claim that there are no studies that indicate exposure risks for humans are increased for children or pregnant women. In fact, it would be highly unethical to conduct such a study. Instead, EPA extrapolates the impact on people based upon data from rodent/animal studies. Volunteers for the study may interpret the CDC’s statements to indicate that the pesticide is safe for people, when in reality it is a potential carcinogen.
Lyme disease is the most prevalent tick-borne disease in the U.S. It is caused by the bacterium Borrelia Burgdorferi that is harbored by several species of ticks, but most significantly the blacklegged tick that is ubiquitous in the northeastern and north central United States. According to Bryan Schwartz, M.D. of John Hopkins University, ticks start their life feeding on smaller hosts, such as small birds and reptiles, but prefer to feed on white-footed mice (Peromyscus leucopus), a notorious transmitter and reservoir of the bacterium. After molting, adult ticks prefer to feed on larger mammals, such as deer and humans, at which time they may have already picked-up the bacterium. An infected tick transmits the disease by biting and attaching itself to its host. Research suggests that a tick must feed for 24-48 hours before B. Burgdorferi is transmitted to the host. This makes proper education and awareness about Lyme disease prevention incredibly important.
Although Beyond Pesticides commends the state for attempting to address this serious disease, we advocate for the least-toxic method of tick control possible. For more information on non-toxic tick control, see our fact sheet.
Take Action: Contact Maryland’s Department of Health and Mental Hygiene and let them know pesticides controls are not the answer to Lyme Disease!
Toll Free Phone: 1-877-4MD-DHMH (1-877-463-3464)
All unattributed positions and opinions in this piece are those of Beyond Pesticides.