For the Birds

A deadly nerve agent kills endangered birds — and it may poison people. Will the EPA have the nerve to ban it?


Who’d have thought that a not-too-distant relative of military nerve gases would be used to rub out wee sparrows, starlings and pigeons? Sound like overkill? Well, that’s literally what happens every time a bird alights on the EPA-approved Rid-A-Bird pesticide perch, with an organophosphate poison that works by seeping into the bird’s feet, inducing tremors, convulsions, suffocation, and for the finale, death.

To make matters worse, the poison goes beyond its intended reach to kill endangered birds like the American peregrine falcon after they prey upon the poisoned “pests” — and scientists say the active ingredient, fenthion, may be poison for people as well.

The EPA has at last decided to phase out Rid-A-Bird, after years of prodding from the U.S. Fish and Wildlife Service (FWS), which monitors the deaths of protected birds that fall into the clutches of the nerve-zapping product. But EPA didn’t defer to its federal counterpart’s wishes — it was prodded to action by a lawsuit and bad press.

In August Weyerhaeuser Co. pleaded guilty to violating the federal Migratory Bird Treaty Act for poisoning two protected birds — a great horned owl and a sharp-shinned hawk — with Rid-A-Bird near its Longview, Wash., paper mill. Placed on probation for five years, Weyerhaeuser promised in court to spend more than $100,000 to study new methods of controlling pest birds without using Rid-A-Bird. Lawyers for both sides criticized the EPA for allowing the use of Rid-A-Bird, which was approved in 1990. The product is already banned in Missouri and New York, but is readily available by mail-order or online.

On the heels of the case, EPA scurried to complete a scheduled review of Rid-A-Bird, and is now negotiating with the manufacturer –a two-man company in Wilton, Iowa — to choose a “safer” replacement for Rid-A-Bird by the end of the year.

But some scientists say that’s not enough. Dr. Mary Henry, a toxicologist with FWS, says that EPA should also rein in the overall use of Rid-A-Bird’s active ingredient, fenthion. In addition to killing birds, fenthion can get into the water and kill freshwater animals like mussels, plankton, and fish, Henry said.

Widely used to kill birds, mosquitoes, and insects that cling to livestock, fenthion is an organophosphate pesticide with the same “mechanism of toxicity” as sarin, the military nerve gas — it causes a buildup of neurotransmitter chemicals that makes the central nervous system go haywire. Sarin recently has been the subject of numerous federal investigations because it may be at the root of the Gulf War illness suffered by returning soldiers.

“There is reason for the EPA to be concerned about fenthion,” said Carey Pope, a toxicologist who worked for the Defense Department this summer investigating the effects of sarin on soldiers. “It tends to hang in [the body] longer than other pesticides.”

While the EPA is not yet willing to recall fenthion, the agency is conducting tests to determine fenthion’s effect on the eyes of humans, and EPA toxicologist William Boyes is reviewing a Japanese study that found a high rate of myopia (nearsightedness) in people exposed to fenthion. Another study, by fenthion manufacturer Bayer Corporation, indicates that rats that were given high doses of fenthion over a period of two years had eye problems as well. “A conservative approach is what is toxic to animals is hurtful to humans,” Boyes said.

Dr. Henry says the scientific community is starting to take a hard look at the widespread pesticidal use of organophosphates, which were first developed by the Germans during World War II. “They are much more toxic than we first thought.”

— Laura Linden is a reporter and freelance writer in San Francisco.