From below:
"When we spray glyphosate on the fields by the rules it has been shown that
it is washed down into the upper ground water with a concentration of 0.54
micrograms per litre. This is very surprising, because we had previously
believed that bacteria in the soil broke down the glyphosate before it
reached the ground water"
-------------------
Denmark has imposed a ban on the spraying of glyphosates as of 15
September 2003 following the release of data which found that
glyphosate, the active ingredient in Monsanto's Roundup herbicide (RR)
has been contaminating the drinking water resources of the country.
The chemical has, against all expectations been sieving down through
the soil and polluting the ground water at a rate of five times more
than the allowed level for drinking water, according to tests done by
the Denmark and Greenland Geological Research Institution (DGGRI) as
reported below.
"When we spray glyphosate on the fields by the rules it has been shown
that it is washed down into the upper ground water with a concentration
of 0.54 micrograms per litre. This is very surprising, because we had
previously believed that bacteria in the soil broke down the glyphosate
before it reached the ground water," says DGGRI.
Increased findings that weeds are developing resistance to Roundup, the
world's most popular herbicide, have some scientists urging new
planting practices. The product's manufacturer says the problem is
being overblown.
Roundup, whose generic name is glyphosate, has been on the market for
more than 30 years. It long has been a favorite of farmers, home
gardeners and golf course greenskeepers because of its effectiveness in
killing weeds.
It allows growers to cut back on tilling, a more labor-intensive and
expensive method of controlling weeds, and does not pollute the
environment.
"Roundup Ready" crops, which have been genetically altered to tolerate
the chemical, now cover much of the nation's farmland since their
development in the late 1990s. They allow farmers to spray the
glyphosate herbicides widely without harming crops.
The Agriculture Department estimates that 80 percent of the 73 million
acres of soybeans in the United States are Roundup Ready soybeans, and
Roundup Ready cotton accounts for more than 30 percent of the 12
million acres planted. The corn variety, still new to the market,
covers 11 percent of 70 million acres.
"Farmers are planting too many Roundup Ready crops," said Stephen
Powles, an expert on weed resistance at the University of Western
Australia.
The herbicide is vital for food production systems in the United States
and in many other parts of the world, Powles said. Should weed
resistance become widespread, he said, "I think the problem will become
a crisis."
In 1996, Australia was the first to note that weed resistance to
glyphosate was developing in rigid ryegrass found in a few grain and
sorghum fields. Five years later, South Africa reported seeing the
resilient rigid ryegrass had infested a few hundred acres of vineyards.
In 2000, University of Delaware scientists reported to the Weed Science
Society of America, which tracks farm chemical resistance, that in some
soybean fields, mare's tail was resisting glyphosate. Since then,
resistant mare's tail has been reported in other states - Indiana,
Kentucky, Maryland, New Jersey, Ohio, Arkansas, Mississippi and
Tennessee.
Far more worrisome are cases in Iowa, Illinois and Missouri, where
glyphosate is becoming ineffective on abundant weeds such as velvet
leaf and water hemp.
Allan Felsot, an environmental toxicologist at Washington State
University, said weeds naturally develop resistance to a pesticide and
dismissed the idea they might be picking up a resistant gene from
Roundup Ready soybeans, corn or cotton.
"Any time you have a place where you're using a strictly singular
herbicide, you may end up with some resistance in some cases," he said.
Nonetheless, some scientists want farmers to alter their planting
practices to assure that Roundup and competing brand names of
glyphosate maintain their effectiveness as a herbicide in the future.
The Australian Powles advocates cutting back on plantings of Roundup
Ready crops.
Mark VanGessel, a weed scientist at the University of Delaware,
advocates a more moderate course. He suggested that farmers rotate
their Roundup Ready crops with conventional varieties.
"My gut reaction is that we do need to limit the use of
glyphosate-resistant crops," VanGessel said. "That doesn't necessarily
mean don't develop them or don't use them altogether, but instead use a
planned approach so to not use the glyphosate-resistant crops year in
and year out."
Monsanto Co., which markets Roundup Ready crops in addition to the
herbicide, said the problem is not nearly that severe.
"Most of the situations that we're dealing with, we're dealing with
very small acres," said Greg Elmore, a soybean technical manager at
Monsanto. "We're not talking about a whole county. In some cases, we
have one field only."
Regardless, farmers could turn to tilling and a combination of other
chemicals besides glyphosate, he said.
Monsanto's competitor, Syngenta, agrees with VanGessel that farmers
should rotate planting of Roundup Ready corn and soybeans with
conventional crops. Syngenta makes its own glyphosate spray, Touchdown.
"We really feel like the problem is real and the problem is growing,"
said Sherry Ford, a Syngenta spokeswoman. "Just like with antibiotics,
an overreliance on one type of solution is going to eventually make
that solution ineffective."
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