As part of the ongoing battle against Lyme and other tickborne diseases, public health organizations are asking residents in 11 Fairfield County towns to participate in a study to see if wiping out the ticks on rodents will help rein in the illnesses in humans.
The investigation, by the Connecticut Emerging Infections Program at Yale School of Public Health, the state Department of Public Health and the federal Centers for Disease Control and Prevention (CDC), involves bait boxes that contain small amounts of a tick-killing pesticide.
The pesticide, fipronil, also happens to be toxic to bees, which are on a worrying decline globally because of a host of threats.
Scientists say the way the pesticide is distributed shouldn't pose a problem. Still, local beekeepers are nervous. Fipronil is one of seven pesticides that environmental campaign group Greenpeace earlier this year called for to be banned because of the danger to bees.
The investigation by health agencies in Connecticut centers on the efficacy of bait boxes. This commercially available system of tick control works like this: mice and other small rodents are attracted to the boxes and when passing through they get a dab of oil containing the pesticide. The dose is about a tenth of what a topical tick treatment for the family pet dog would contain, but is enough to kill all the ticks on the creature. (The bacterium that causes Lyme is passed to humans by the bite of an infected black-legged tick.)
The study is seeking 500 residents in 11 Fairfield County towns, including Easton and Bethel, and four towns in Litchfield County because of the high number of Lyme disease cases and the abundance of tick habitats in those communities, said Sara Niesobecki, a research associate for the emerging infections program. Some of the homeowners will get boxes containing pesticides and some will get placebos; participants get a $195 gift card for their trouble. A pilot study last year involved 125 homes.
Norwalk-based company Tick Box Technology Corp makes the Select TCS Tick Control System boxes and owns the technology; a sister company has been installing the boxes for Connecticut property owners for more than a decade. The system was invented by the CDC and was owned by chemical giants Aventis and Bayer before Tick Box Technology bought it, said company co-owner Dave Whitman.
The pesticide fipronil, contained in the boxes, is made by chemical giant BASF. It is found in more than 50 registered products, including termite control and crop treatments, according to the National Pesticide Information Center. BASF says it's registered for the control of more than 200 insect pests.
Scientists say there's not a direct path for the pesticide on the rodents to reach honeybees. "Bees are collecting pollen, they're collecting nectar, they're collecting water," said Dr. Kim Stoner, associate agricultural scientist at the Connecticut Agricultural Experiment Station. "In that particular [bait box] scenario I don't see an obvious route of exposure for honeybees." However she said bumblebees could be affected because they often make their nests in abandoned mouse nests.
Dave Blocher, a beekeeper and honey seller in Easton, said he would be hesitant to take part in any such research because he has had recent problems with pesticides. He said two of his bee colonies died in May and June last year and fipronil was found in the samples that he sent to the Connecticut Agricultural Experiment Station for analysis. "When bees come in contact with this pesticide, it has devastating effects on the colony," he said. Still, he's puzzled as to how the chemical would have got to the bees. (He lost a significant number of bees in another episode last year and the pesticide methomyl was found in those dead bee samples, he said.)
Author and beekeeper Marina Marchese, who owns Red Bee Honey, says she does not use any pesticides on her property and would not take part in the study. "Many beekeepers lose colonies from pesticide poisoning beyond just tick spray," said Marchese, who runs a honeybee farm in Weston. "These affect all pollinators."
Bees are pollinators, and it is estimated that pollinators are responsible, directly or indirectly, for between a quarter and a third of the food on our plates, according to the U.S. Department of Agriculture. Without bees to pollinate them, crops would be threatened, leading to shortages and higher food prices.
Bees are declining particularly in Europe and North America, a report from Greenpeace noted in April. As well as pesticides, the report pointed to disease, parasites and climate change as factors in declining bee populations globally.
In late April, the European Union decided to restrict the use of three neonicotinoid chemicals — clothianidin, imidacloprid and thiametoxam — because of worries about bee health. And, in the U.S. last month a group of beekeepers and environmental groups sued the Environmental Protection Agency over the proliferation of two of those chemicals, which they say are a cause of Colony Collapse Disorder (CCD).
In the U.S., CCD has been devastating honey bee colonies since 2006, when farmers began reporting losses of their hives with no apparent cause, the U.S. Department of Agriculture says. Still, there have been no CCD cases documented in Connecticut, said State Entomologist Dr Kirby Stafford. "But that is not say we haven't had losses, sometimes substantial, from other causes," he said, noting that Varroa mites continue to be one of the leading problems.
Beekeepers are ever cautious. Howland Blackiston, a founder member of the Back Yard Beekeepers Association, a southwestern Connecticut group with some 400 members, said beekeepers get very concerned regarding any use of bee-harming pesticides.
The bait box study "is likely a fairly 'safe' approach for the bees, as it does not involve spraying of the chemical," he said. "That's the good news. But nevertheless I get nervous whenever dangerous chemicals are introduced to the environment."