HEADER SECTION

The following is the unedited version of an op-ed piece which appeared in The Journal News, Monday, June 25, 2001.

"Lessons From Birds and West Nile Virus"
by Robert Foster
CCE Legislative Director

Birds have long been recognized and valued for their ability to perform as sentinels in the service of human endeavor. Valued for their elevated perspective and superior vision…yes, but even more so for their sensitivity to environmental conditions such as deadly gases in a coal mine or emerging diseases, like West Nile Virus (WNV). In fact the New York State West Nile Virus Response Plan (New York State Department of Health, 2000 & 2001) relies heavily upon the sensitivity of birds, particularly crows, as indicators of WNV in the environment. But sentinels, it is their nature after all, often see more than that for which they look. Such was the case last year for the proud regiment of avian fauna from New York State. They were dutifully alert for WNV and found it, but what they found more, were toxins such as pesticides.

In fact, according to New York State wildlife pathologist, Ward Stone, pesticides killed more of the birds sent to his unit for examination in 2000 than did WNV. Not the pesticides sprayed from trucks into neighborhoods to control the mosquitoes feared to carry the disease, but the more common pesticides available to consumers in a variety of products at a variety of venues. Among the more frequent causes of bird death were broad band insecticides from the organophosphate category such as Dursban, diazinon and ethyl parathion. Organophosphates, according to the United States Environmental Protection Agency (EPA) are "efficiently absorbed by inhalation, ingestion and skin penetration" and were the class of pesticides most often implicated in symptomatic illnesses among people in 1996*. Some of the avian victims ate the poisoned insects while others foraged on tainted grain.

The anticoagulant rodenticides also bear mentioning, not only for their prowess in causing bird fatalities, but for the leap they take taxonomically in their target pest. Rodents, like people, are mammals, and the toxicity of rodenticides can be very similar for rodents and people. This coupled with the placement of baits in environments shared by humans and other mammals make rodenticides a particular risk for accidental poisonings. Once again, the birds either ate the doomed rodents, dooming themselves or fed on seeds and grain laced with the poison.

Dead bird surveillance for WNV has helped illuminate the widespread and indiscriminate use of pesticides in our society. To think that pesticides are sophisticated to the point of relegating adverse impacts exclusively to the target organism is tragically shallow and inexcusable given the facts.

But for many, the quiet but profound warnings found in dead birds will go unnoticed and unheeded without the compelling evidence of direct human impact. For that, WNV has also provided some illumination. In 2000, fourteen people were hospitalized in New York State with WNV, and hundreds of people contacted health officials with complaints of health impacts from exposure to the pesticides used for WNV control activities carried out by local health departments. Of these, twenty-two actually made it onto the NYS Department of Health's Pesticide Poisoning Registry. These cases were discovered with very little surveillance for pesticide exposure to people, compared with the unprecedented surveillance for human cases of WNV. This does not include the poisonings that occurred, some never diagnosed, as a result of exposure to the same home and garden pesticides that are killing our birds.

What if we looked for symptoms of pesticide exposure as diligently as we look for symptoms of vector-borne diseases like WNV? Prudence and wisdom suggest we recognize and try to benefit from the sacrifices made by our bird sentinels. Given the daunting dead bird data, public health policy should reflect as much concern for human pesticide exposure as it does for diseases like WNV. Surveillance for pesticide exposure should be given as high a priority as disease surveillance.

Let us not forget our noble sentinel birds; if they are to die in the line of duty, they should be counted and examined. There may be much more they have seen and much more they have to tell. The United States Department of Agriculture has set up a dead-bird hot line for New York State (866-537-bird) so that the birds can be counted and their stories told.

Finally we must reduce the habitual use of pesticides. At this time of year, while birds are nesting and raising their young, like clockwork chemical pesticides are applied to lawns and trees in neighborhoods throughout the state and around the country, and for what purpose? Often for no purpose other than it is part of the service provided by professional landscapers, or because pesticides are ingredients of products marketed for lawn care. Before considering the application of pesticides this growing season, consider the message from the birds and what it may mean for human health and the health of our natural environment, upon which we so dearly depend.

* Reigart, J.R., Roberts, J. R., Recognition and Management of Pesticide Poisonings, Fifth Edition, United States Environmental Protection Agency, 1999.