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Letter from FIEC Board Member Leslie T. Sharpe on Pesticides

Sept. 27, 2000

Superintendent Constantine Dillon

Fire Island National Seashore

Thank you for your thoughtful--and thorough--response to my email (9/20/00) expressing concern over the authorization of aerial spraying of pesticides over portions of Fire Island.

Your statement that FINS does not regard adulticides as a "preferred alternative" in responding to mosquitoes is reassuring. Even in those FI communities that have authorized the use of low-impact pesticides to control mosquitoes (and any potential outbreak of WNV), there has been some concern about the potential toxic effects of such pesticides on both the human and natural environment. But the possibility of the aerial-spraying of pesticides has raised that concern to the level of anxiety and apprehension.

Numerous issues need to be considered--and, hopefully, will be--before such an action is taken: They include:

1) WNV v. Pesticides: Balancing Health Considerations. Consider these facts about WNV: The odds of contracting WNV, even in an infected area, are extremely slight. Only one percent of mosquitoes carry the virus. A bite by a virus-bearing mosquito has a 1 in 350 chance of infection. Even then, fewer than 1% of those infected become ill. This year, only 12 people have contracted WNV in NYS (all in in NYC)--none have died. In comparison, over 2,000 people in our region died from the flu last year!

WNV, as a health hazard, is certainly not negligible, even though no less an expert than Dr. Anthony Faucci, Director of National Institutes of Health, has characterized WNV as a "mild illness"--and the fact is that WNV has had few serious health effects on the general public. (The recent outbreak of WNV in Israel raises some interesting questions--but should not necessarily add to the panic about WNV here. Israel, which has known WNV for decades--indeed virtually every wild bird species and 15% of the population have antibodies to WNV--seems to suffer such outbreaks in 10-year cycles. That in itself is information that could add to our ability to fight WNV on our shores.)

The New York Times (9/25/00), in an article titled "West Nile Virus Data Cheers, and Puzzles, Health Officials," points out that the preferred target of WNV-carrying mosquitoes are birds and other animals--not people (the rate of infection of the former rose significantly and spread geographically this year, while the number of human beings who contracted the virus actually dropped). (The same is true of lyme disease, whose carriers, deer ticks, prefer deer, mice, and other animals as principal hosts.) The implication of this finding is that the best way to protect against WNV is for people to take individual actions, that is, clearing standing water that Culex, WNV's principal vector, uses to breed, wearing appropriately protective clothing at appropriate times, applying topical insect repellent when necessary. As significant is the finding in the same article that "in spite of the widely published theory that children are among the most likely to become very sick from WNV, the cases prove otherwise." The average age of a New Yorker infected over the last two years was 77, and only a single child was reported with symptoms last year.

Many Fire Island towns self-identify as "family communities," and all, as summer resorts, have many children. No doubt concern for children as potential victims of WNV was a prime factor in the decision of certain communities to spray this past summer. But this concern, especially in light of the above findings, must be balanced by this known fact: children face particular risks from pesticides, for two main reasons. First, they are more exposed to pesticides than adults, because of their smaller size; and second, children's developing bodies and brains are more susceptible to toxins than adults.

As early as 1987, the National Cancer Institute found that children living in homes where garden pesticides were used had as much as a 6-fold greater chance of developing childhood leukemia. In another study, the risk of childhood brain cancer increased 2 to 4-fold in families that used garden pesticides. Pesticides were cited in a 1990 Congressional Report titled "Neurotoxicity, Identifying and Controlling Poisons of the Nervous System," which pointed out that "the adverse effects on organs and organ systems, particularly the nervous system, may pose an equal or greater threat to public health [than cancer]."

It also makes this important point: "What scientific and epidemiological data there is suggest pesticide poisoning prevails despite existing protective measures," and cautions that "fetuses and children are in the high risk group of being adversely affected by neurotoxic substances." That these concerns are ongoing was shown by the establishment of the first center to study the effect of pesticides on children--in 1998--at U-C Berkeley, as part of a federally funded (through EPA) initiative focusing on children's health.

Finally, the Pesticide Neighbor Notification Act, which allows parents and neighborhood residents to be notified of when pesticides are being used around their homes, was passed by the NYS Legislature and signed into law by Governor Pataki this spring (NB that a leader in supporting this statewide legislation was Long Island, where "cancer clusters" of breast cancer and other rarer cancers are attributed to years of pesticide application and the use of chemical fertilizers), had as a primary motivation that children are particularly susceptible to health risks from pesticide exposures.

It is arguable that pesticide spraying--especially aerial spraying, which by nature is untargeted and indiscriminate, potentially poses a greater health risk to FI's families, and especially children, than WNV.

2) Pesticides and the Environment: Too Steep a Price? Anvil (Sumithrin), as a Pyrethroid insecticide, is prohibited from being applied to "open water or within 100 feet of lakes, streams, rivers, or bays." Fire Island, which is, at its maximum, only several hundred yards wide, is bounded by the Atlantic Ocean and the Great South Bay. There is no way that aerial spraying would not impact these waters. The jury is still out on what caused the die-off of 90% of the lobsters of Long Island Sound last fall. Yes, they are cold-water critters, and last year's temperatures were unusually high. But lobsters molt in the fall--at the exact time when pesticides were entering the system as run-off last year. And, at least according to the lobstermen, whose jobs--and even industry--have been lost for at least the next decade, the kill started then, after the application of Malathion on Long Island. (NB that NYC abandoned Malathion in its pesticide applications this year because of concerns over toxicity. As a substance that is still under review by EPA--and that is banned in Great Britain--Malathion's remaining in Suffolk County's "arsenal" of pesticides is disconcerting.)

This year, we have also witnessed a die-off of blue crabs in the Great South Bay--again, baymen attest that this phenomenon is linked to pesticides--specifically the spraying of Anvil in Brookhaven Township this summer. The Great South Bay has also suffered the worst brown tide since the Peconic brown tide in 1986. We know that brown tide is the result of hypoxia--but what causes that hypoxia? Certainly it is reasonable to suppose that the warm weather and warm waters of last summer heated what is, in effect, a toxic brew in the GSB. But the brown tide, as a phenomenon (at least in the extreme manifestations we have seen) is not a natural one.

Our best guess is that "overfertilization" of waters--nitrates from nonpoint source pollution such as run-off as well as point source pollution such as sewage overflows--play a key role in these blooms. Pesticides entering the system, also as run-off, contribute to the degradation of the ecosystem's immune system, as well as that of crustaceans such as lobsters and crabs, which, like insects, are arthropods and especially susceptible to pesticide poisoning.

My ultimate concern about spraying is that it is a short-term solution to a long-term problem. Pesticides, even Anvil, a synthetic that mimics "natural" toxins, kills beneficial insects--pollinators such as bees and insectivores such as dragonflies (the mosquito's natural enemy), praying mantises, and spiders (not to mention amphibians and reptiles!). Butterflies, in particular the monarch, which has disappeared from its migratory route through Fire Island this fall, have become poster bugs not only for environmental degradation but for the ethics of our actions. I am not sentimentalizing insects--merely pointing out that we are attacking the food chain from the bottom up. If we don't feel the impact of our actions, our kids certainly will.

Another issue to ponder is this: We might actually be increasing mosquito populations by aerial spraying. A paper by Howard et al. (Journal of the Am. Mosquito Control Assoc., Dec; 13 (4): 315-25, 1997) reports on analyses of 11 years (1984-94) of mosquito collection data from swamps in upstate NY. The finding: aerial mosquito adulticide applications used in response to EEE outbreaks were successful in achieving short-term reductions in mosquito abundance. However, despite repetitive applications, populations of the primary vector of EEE virus, Cs. melanura, have increased 15-fold.

Now, this is just one study--and I am aware that it is criticized for having "flaws in the analysis." But I am also aware that "bad science" is always on the other side of an issue, especially when research threatens the status quo. At the least, this study raises intriguing questions about the effectiveness of aerial mosquito adulticide applications, and should be used as a jumping-off point for additional studies where "sound analysis" is assured.

3) Adulticides v. Larvacides: Get 'Em When They're Young! Clearly, the way out of the "emergency" prompted by WNV will involve a lot of different techniques. For starters, we need to know a lot more about WNV, in order to know how little adult control we can get away with. But one thing we can agree on: the most effective and efficient and certainly the safest method of control is to attack mosquitoes in their larval stage. Identifying and monitoring breeding grounds, and applying larvacidal "dunks" (and using, as Saltair has for over a decade, natural predators such as larva-eating fish, dragonflies, and insectivorous birds such as tree swallows) is our first line of defense. Now, I realize that the use of larvacides will not kill all mosquitoes--but neither will pesticides. But locating, treating, and continuing to monitor breeding grounds in both the natural and human world of FINS would certainly be a strong, strategic first step.

Culex, the primary vector for WNV, is a fresh-water vector largely dependent on human habitation to supply its breeding grounds. Though the steps FINS has taken to educate the public about protecting one's person and property are laudatory, the point is that most people just don't know--or don't know how important it is (and how much help it can be)--to do something as simple as remove standing water from their premises. I, for one, have never seen the brochure "Mosquitoes and You"--that's the kind of info that should be available at FI ferries as well as at all FI town centers (I can hear the collective business interests of FI groan, believing that raising the issue would discourage visitors. But WNV is here to stay, and people aren't leaving the region because of it. WNV isn't contagious, but fear is. If you inform people, you reduce their fear, and if you give them ways to protect themselves, you reassure them and empower them. And people can learn--they have with lyme disease, for starters.)

We really need, in the FI communities, more outreach from both FINS and SC Vector Control in this area. Communities that desire to institute programs of water management and biological larval control should be supported and able to turn to FINS and SCVC for their advice and expertise. Other varieties of mosquitoes, such as Aedes and the salt marsh varieties, are also potential vectors for WNV. These breed in natural areas of FINS, such as the Otis Pike Wilderness and areas such as the one between Saltair and Kismet. Here's the condundrum:

These "wild" breeding sites, on FI, come under the purview of FINS, whose mandate includes a policy of complete noninterference in natural processes. As a naturalist and former NYC Audubon Vice President, I am largely in support of this policy and leery of any human interference in nature in general--let alone in an ecosystem as frail as the barrier beach. But it seems to me only common sense to "interfere" in nature in the least invasive way, with the least impact on the ecosystem (that is, by using environmentally safe biocides such as "dunks" in FINS salt- and fresh water wetlands) before WNV takes hold, becomes widespread, and pesticide spraying is demanded even in FINS natural areas.

At the very least, it seems reasonable--even vital--for FINS to consider a program of limited water management and biological larval control in the areas of FINS that border the communities. The last thing any of us who love this barrier beach that is Fire Island want to see is pristine areas such as the Wilderness and Sunken Forest demonized by a panicky public as unchecked breeding grounds for WNV-carrying mosquitoes. It seems that, in this case, an ounce of prevention really is worth a pound of cure.

In conclusion:

Aerial spraying of pesticides arguably poses a long-term health risk that is at least as great--if not greater--to residents of FI as WNV. The potential negative impacts of aerial spraying on a frail barrier beach ecosystem such as FI and its surrounding waters are enormous--and perhaps are being seen already as a result of Long Island's pesticide spraying of the past two years.

The application of larvacides is the most effective way to kill mosquitoes. Programs of water management and biological larval control should be set up in communities that want them with the help of FINS and SCVC. At the same time, FINS should considering applying such larvacides to sites in the Wilderness and other natural areas. At the very least, FINS should consider instituting limited water management and biological larval controls in the FINS areas bordering communities.

Thank you for your forbearance. We look forward to working with you.

Very respectfully yours,

Leslie T. Sharpe, CGPOA Vector Control Committee

Updated 28 October 00