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Fwd: [earthsave-boston] Pollen From Genetically Altered Corn Threatens Monar...


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<<"Nobody had considered this before," said Dr. Fred Gould, insect ecologist
North Carolina State University. >>

Nobody who was anybody, anyway!

- Nina

> -----Original Message-----
> From:	Norio Kushi []
> Sent:	Thursday, May 20, 1999 10:54 AM
> To:; EarthSave Boston
> Cc:	Dick Kaynor
> Subject:	[earthsave-boston] Pollen From Genetically Altered Corn
> Threatens Monarch Butterfly, Study Finds
> This is copied from the NY Times web site today - Norio
> May 20, 1999
> Pollen From Genetically Altered Corn Threatens Monarch Butterfly, Study
> Finds
> ll around the country, farmers are about to finish sowing millions of
> acres of
> a genetically altered form of corn that protects itself from pests by
> producing a toxin in its tissues. But researchers report on Thursday that
> this
> increasingly popular transgenic plant, thought to be harmless to nonpest
> insects, produces a wind-borne pollen that can kill monarch butterflies --
> a
> species that claims the corn belt as the heart of its breeding range. 
> Researchers said that the laboratory study, conducted by a team from
> Cornell
> University, provides the first evidence that pollen from a transgenic
> plant
> can be harmful to nonpest species. As such, the study is likely to become
> part
> of the growing debate about whether genetically engineered crops may have
> unforeseen effects on the environment. 
> Transgenic crops have proven tremendously popular with American farmers in
> recent years. This season the new pest-resistant corn, introduced by seed
> companies just three years ago, is being planted on an estimated 10
> million to
> 20 million acres out of an 80-million-acre corn crop nationwide. Known as
> Bt
> corn, it carries a gene derived from a bacterium, Bacillus thuringiensis,
> that
> produces the Bt toxin, killing corn borer pests that try to eat the plant.
> The researchers fed monarch caterpillars leaves of milkweed, their only
> food,
> which had been dusted with Bt corn pollen, regular corn pollen or no
> pollen.
> Half of those fed Bt corn pollen died within four days, while all those
> fed
> regular corn pollen or no pollen survived. The study, published on
> Thursday in
> the journal Nature, was written by Dr. John E. Losey, an entomologist, Dr.
> Linda S. Rayor, a behavioral ecologist, and Maureen E. Carter, a
> biologist. 
> The Bt toxin itself is already known to be lethal to many butterflies and
> moths. Researchers said this suggests that butterfly or moth species other
> than the monarch could be affected by the transgenic plant, particularly
> those
> that live on plants like milkweeds that are often found in and around corn
> fields and could be dusted by Bt corn pollen. But researchers note that
> the
> effect of Bt corn pollen on populations of wild insects is unknown. 
> Academic researchers praised the study as a first step toward
> understanding a
> previously unsuspected risk. 
> "Nobody had considered this before," said Dr. Fred Gould, insect ecologist
> at
> North Carolina State University. "Should we be concerned? Yes." 
> Dr. John Obrycki, an entomologist at Iowa State University, called the new
> study "solid" and said: "You now have a novel means of distributing Bt
> toxins
> in the environment. This is a technology that's being promoted and we
> haven't
> really considered all the consequences." 
> Representatives from Novartis Agribusiness Biotechnology, Monsanto and
> Pioneer
> Hi-Bred International Inc., the top sellers of Bt corn, challenged the
> significance of the findings for monarch caterpillars, also known as
> larvae,
> outside the laboratory. Researchers estimate that Bt corn is a product
> worth
> hundreds of millions of dollars annually. 
> Taking issue with the methods and conclusions of the study, Rich Lotstein,
> vice president of public affairs for Novartis Agribusiness Biotechnology,
> said, "Even if Dr. Losey's results are real, which they could be, the
> exposure
> is still minimal, and the impact is extremely small, if any." 
> Researchers, including the authors, said it is still unknown how much of
> an
> impact Bt corn pollen is having on wild monarch populations. 
> "I would be very surprised if there are no monarch larvae being killed,"
> Losey
> said. But he added, how many are being killed, "that's the big question." 
> Researchers said they do know from a study published last year that it is
> the
> corn belt, which includes such states as Iowa, Illinois, Indiana and Ohio,
> that produces about half of the monarchs that migrate each year to Mexico.
> And across that geographic expanse, said Dr. Karen Oberhauser, an
> ecologist at
> the University of Minnesota, there was certainly potential for corn pollen
> and
> monarch caterpillars to cross paths. "There are a lot of monarch larvae
> around
> in July and August and that's when pollen is being shed," she said. "The
> timing is exactly wrong." 
> How much milkweed is close enough to corn fields to be at risk of
> receiving a
> dusting of pollen is unknown. But as Dr. Marlin Rice, entomologist at Iowa
> State University, put it, in many heavily farmed states, "if you're a
> monarch,
> odds are you're going to be close to a cornfield." 
> Monarchs are not considered endangered, but Dr. Lincoln Brower, a monarch
> biologist at Sweet Briar College in Sweet Briar, Va., said the butterfly
> faces
> a growing number of pressures. The No. 1 threat, he said, is still logging
> in
> the butterfly's winter resting grounds in Mexico. Other threats include
> roadside mowing and the use of herbicides on milkweeds. 
> Whatever level of threat Bt corn pollen turns out to pose, it is almost
> certainly less damaging to monarchs and insect diversity in general than
> the
> spraying of insecticides. But Obrycki said that in many areas of the
> country,
> farmers do not typically spray for corn borer. 
> Still others viewed the new study as a broader sign of the danger of
> transgenic crops and the need for tighter regulation. 
> Dr. Margaret Mellon, director of the agriculture and biotechnology program
> at
> the Union of Concerned Scientists, said: "Why is it that this study was
> not
> done before the approval of Bt corn? This is 20 million acres of Bt corn
> too
> late. This should serve as a warning that there are more unpleasant
> surprises
> ahead." 
> Dr. Phillip O. Hutton, chief of the microbial pesticides branch at the
> Environmental Protection Agency, which regulates the commercial
> availability
> of Bt corn, declined to comment on the new study, saying the paper had not
> yet
> gone through the agency's scientific review. In addition to Bt corn, the
> has approved Bt potatoes and Bt cotton, both of which are commercially
> available. 
> For the farmers, losses of monarch butterflies -- which neither help nor
> hurt
> crops -- may be hard to measure against the gains from this powerful new
> product. Previously, farmers had to scout their crops diligently for signs
> of
> the corn borer and spray at just the right time in an infestation to kill
> them. Now they can plant Bt corn and let the internally produced toxins do
> all
> the work. 
> "It's an amazing technology," said David Linn, a corn and soybean farmer
> in
> Correctionville, Iowa, who plants Bt and regular corn. "Does it kill more
> monarchs or not? That's so far down on the list of things we have to
> decide
> about." 
> Monarch caterpillars eating a milkweed leaf, that was dusted with pollen
> from
> corn that has been genetically altered to kill pests. A study says the
> pollen
> has been found to kill the butterflies, which breed in the corn belt. Kent
> Loeffler/Cornell University 
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