Out of Control

So deadly is malathion to aquatic life that the EPA forbids its use over water; but since this was "a public health emergency," city officials got the Department of Environmental Conservation to waive the regulation.

Unlike most native birds, butterflies can thrive in a megalopolis. In New York City, for instance, you can see 80 species--not just migrating through the city but actually living there. So as part of the Pipe Dream Project (the North American Butterfly Association's nationwide effort to bring back pipe-vine swallowtails), Steven Coates of Brooklyn planted pipe vine in his backyard in the spring of 2000. Brooklyn is near the extreme northern range of the pipe-vine swallowtail, and Coates had never seen one in the area, but to his astonishment he found three egg clusters on his pipe vine in July. About 48 hours after the eggs hatched, the city sprayed. Next morning, all Coates's caterpillars were dead.

We see many more butterflies in Grafton today than we did 10 years ago, and while we can't prove cause and effect, it seems more than coincidental that we dismissed the Central Massachusetts Mosquito Control Project 10 years ago. But why are we also seeing a lot fewer mosquitoes? Tufts University professor Sheldon Krimsky, pesticide risk-assessment adviser to the Massachusetts Department of Public Health's Working Group on West Nile Virus, offers this explanation: "The pesticides kill the predators of mosquitoes, so when the mosquitoes return, as they always do, they may return to a much more supportive environment. . . . The mosquito-control people will make you think that without their programs there will be havoc, that the mosquitoes will just take over. They walk around with anecdotal information--'We kill 40 percent of the mosquitoes,' etc.--but they have nothing published. They are spraying neurotoxins and carcinogens around. If you're doing this, it had better be justified. It hasn't been."

Moreover, Krimsky and other public-health authorities warn that routine, pesticide-based mosquito projects, ongoing in most states, may impede real disease control, should it ever become necessary, by creating chemical resistance in local mosquito populations.

Grafton joined the Central Massachusetts Mosquito Control Project in 1976 largely because urban emigrants who had built their houses near or in swamps were outraged when they got bitten by mosquitoes. We severed ourselves from the project in 1991 because of its expense, its danger to nontarget organisms, including people, and its gross ineffectiveness. But in March 2001 project personnel blew back into town, terrifying the Boards of Health and Selectmen with stories about this new mosquito-borne killer virus called West Nile. They would protect Grafton residents from the epidemic, they said, and all we'd have to do was pay them $96,000. "If we save only one person, it will be worth it," proclaimed one selectman. "Don't shake your head, young lady," boomed another at master bird bander and environmental educator Sue Finnegan, who a decade earlier had almost single-handedly persuaded the town to fire the mosquito controllers. Once again Finnegan and other knowledgeable residents tried to warn the town fathers that routine nuisance-mosquito control wouldn't save anyone from anything, even itchy skin; but this time they were basically told to shut up. Then, with no public participation, the Board of Health placed the item on the warrant for a vote at the town meeting in mid-May.

There wasn't much time to reeducate the town, but at the request of the Grafton Conservation Commission I began collecting information on what we'd be getting for our $96,000. What diseases would they be protecting us from? I asked the Central Massachusetts Mosquito Control Project superintendent, Ken Courtemanche, and the assistant superintendent, Timothy Deschamps. West Nile virus, eastern equine encephalitis, and heartworm in dogs, I was told. Two months earlier the CDC had backed off on its advice to nuke a two-mile radius around every dead bird, and instead recommended no spraying unless "the presence of infected adult mosquitoes poses a risk to health." Superintendent Courtemanche hadn't heard about this. How bad was West Nile in Massachusetts? I asked. Well, no one had gotten it yet. And how bad was eastern equine encephalitis in their service area? Well, no one had gotten it yet. I knew that central Massachusetts dogs get heartworm, but not if you give them preventive medication once a month. How do you know which wetlands to larvicide? Field technicians perform dipping procedures and bring back samples to be identified by the staff entomologist. So the entomologist decides? No, the field technicians decide. And what is their average education? High school. How do you decide when to spray for adults? If someone complains about mosquitoes, and by "landing rates"--i.e., how many mosquitoes land on a technician in five minutes. What if I don't want to be sprayed? You need to make a formal request by registered letter to the town clerk, listing your property abutters, send a carbon copy to the project, and festoon your property with these attractive paper pie plates that say, "No Spray." And what about drift? We'll stop spraying 150 feet from your house. But how can you know where my property line is when I don't, and wouldn't this unfairly deprive my neighbors on both sides of the benefits of spray? We have portable foggers. What's the flight range of a mosquito? Depending on the species, up to 25 miles. Which adulticide will be used in Grafton? Resmethrin, a synthetic pyrethroid. What are the effects on nontarget organisms, including people? Caffeine is more toxic.

Other sources were less sanguine. Professor David Ozonoff, the chair of Boston University's Department of Environmental Health and an adviser to the Massachusetts Department of Public Health on West Nile virus policy, told me this: "It's not just resmethrin; it's resmethrin with a synergist called piperonyl butoxide, which causes cancer in rats and mice [the same stuff New Yorkers were forced to assimilate last year]. I would never use these pesticides for nuisance control, because the risk equation doesn't work. You're not getting any real benefit for public health." Lab studies indicate that synthetic pyrethroids are endocrine disrupters and hormone replicators. For this reason, the EPA rates them as among the most dangerous to children of all pesticides in common use.

"Here's the analogy I use," says Krimsky. "If there were a vaccine being considered for West Nile virus, we would require by law that it be safe and effective. I say we should ask for nothing less, maybe even more, for any spraying, because at least with a vaccine you can decide you don't want to take it. If someone can't demonstrate that a program will prevent West Nile virus, which is very low risk to begin with, why should we accept such an intervention?"

That question should have been asked by the Grafton Boards of Health and Selectmen. The business of the Grafton Conservation Commission, on the other hand, is to protect land, water, fish, and wildlife, and, to that end, enforce the commonwealth's Wetlands Protection Act. So the commission was distressed to learn that Massachusetts mosquito-control projects, which are exempt from wetlands regulations, routinely allow themselves to be used by development interests as a means of circumventing wetlands permitting processes. In 1974, when I worked for the Massachusetts Division of Fisheries and Wildlife, I was sent to Mansfield to investigate the destruction by mosquito controllers of Hodges Brook. I was appalled at what I found. The last real trout stream in town had been converted into a straight, sterile gutter--not to control mosquitoes but to dry out the floodplain for the convenience of developers, who were already building houses when I arrived. Our southeast district manager called it a "clever little conspiracy perpetrated by special interests." A quarter-century later nothing had changed. Writing on her own time and as a private citizen, Maryann DiPinto of the Massachusetts Department of Environmental Protection chronicled similar capers in the late 1990s. In Westborough she observed the Central Massachusetts Mosquito Control Project excavating and polluting a tributary of Jackstraw Brook (a trout stream) and piling the dredge spoils "without any erosion controls." The work, they informed her, had been undertaken simply because the town Department of Public Works had asked for it. In Milford, DiPinto reported that project personnel--again at the request of the town DPW--destroyed 1,000 feet of significant stream habitat, dumping the spoils, including "large boulders, some over six feet in diameter, [on] the bordering vegetated wetland." In Blackstone, against the wishes of the property owner, the Central Massachusetts Mosquito Control Project ditched "800 linear feet of stream [and] spread the spoils, including large stones and boulders, over the adjacent wetland."

Mosquito controllers who depend on this type of "source reduction," as they call it, and on chemical pesticides can never succeed because, along with a few mosquitoes, they take out whole ecosystems, including such natural controls as frogs, toads, salamanders, fish, damselflies, dragonflies, and birds. If birds aren't killed directly, hatchlings may starve when insects are poisoned off, and exhausted migrants may not be able to fuel up for the next leg of their journey.