(Beyond Pesticides, September 2, 2011) The widely used herbicide glyphosate, the active ingredient in Roundup, has been detected in significant levels in rain and rivers in agricultural areas across the Mississippi River watershed, according to two new studies released this month by the U.S. Geological Survey (USGS). The studies’ results raise serious concerns about public exposure and potential environmental damages. Detailed results are available in “Occurrence and fate of the herbicide glyphosate and its degradate aminomethylphosphonic acid in the atmosphere,” published in Environmental Toxicology and Chemistry and in “Fate and transport of glyphosate and aminomethylphosphonic acid in surface waters of agricultural basins,” published online in Pest Management Science.
Glyphosate is used in almost all agricultural and urban areas of the United States. The greatest glyphosate use is in the Mississippi River basin, where most applications are for weed control on genetically-modified corn, soybeans and cotton. Overall, agricultural use of glyphosate has increased from less than 11,000 tons in 1992 to more than 88,000 tons in 2007.
The two studies conducted by USGS examine glyphosate content in air and water samples in the states of Iowa and Mississippi across two growing seasons. The results show that glyphosate is detected 60-100% of the time in both air and rain samples. The consistent occurrence of glyphosate in streams and air indicates its transport from its point of use into the broader environment. The frequency of detection in air samples is roughly similar to the levels observed for other common herbicides in the region, but its concentration in rainfall is found to be at higher levels than for any other previously monitored pesticide.
Additionally, glyphosate persists in streams throughout the growing season in Iowa and Mississippi, but is generally not observed during other times of the year. The degradation product of glyphosate, aminomethylphosphonic acid (AMPA), which has a longer environmental lifetime, is also frequently detected in streams and rain.
USGS researchers did not examine the implications or monitor the effects of the detected contamination, saying that more research is needed to assess any potential damages to public health or the environment. However, such widespread contamination is cause for significant concern, as glyphosate has been linked to a number of serious human health effects, including increased cancer risk, neurotoxicity, and birth defects, as well as eye, skin, and respiratory irritation. Additionally, one of the inert ingredients in product formulations of Roundup, polyoxyethyleneamine (POEA), kills human embryonic cells. The chemical is also of particular concern due to its toxicity to aquatic species as well as instances of serious human health effects from acute exposure.
“Though glyphosate is the mostly widely used herbicide in the world, we know very little about its long term effects to the environment,” says Paul Capel, Ph.D., USGS chemist and an author on both of the studies. “This study is one of the first to document the consistent occurrence of this chemical in streams, rain and air throughout the growing season. This is crucial information for understanding where management efforts for this chemical would best be focused.”
Monsanto created â€śRoundup Readyâ€ť crops to withstand its Roundup herbicide (with the active ingredient glyphosate). Growing previous Roundup Ready crops such as soy, cotton, and corn has led to greater use of herbicides. It has also led to the spread of herbicide resistant weeds on millions of acres throughout the U.S. and other countries where such crops are grown, as well as contamination of conventional and organic crops, which has been costly to U.S. farmers. Because of GE crops, Roundup has become the most popular pesticide ever.
These new studies come on the heels of other recent research showing that glyphosate harms soil and reduces farmland fertility. According to a researcher at the U.S. Department of Agricultureâ€™s Agricultural Research Service, glyphosate impacts the root structure of plants, and 15 years of research indicates that the chemical could be causing fungal root disease.
USGS has submitted the studies to the U.S. Environmental Protection Agency (EPA) to be included in data that is being considered as EPA reviews the registration of glyphosate. The agency expects the review to be complete by 2015, at which point it will issue a decision to either continue to allow unrestricted use of glyphosate or to put limitations or a ban on the chemical in light of emerging science.
Beyond Pesticides is currently involved in multiple lawsuits involving Roundup Ready and other GE crops. The first lawsuit is filed against the U.S. Fish and Wildlife Service (FWS) and seeks to end cultivation of GE crops on twenty-five national wildlife refuges across the U.S. Southeast. The suit is the latest step in a campaign to banish GE crops from all refuges. Filed in the U.S. District Court for the District of Columbia on August 12, 2011 by Public Employees for Environmental Responsibility (PEER), the Center for Food Safety (CFS), and Beyond Pesticides, the federal suit charges that FWS unlawfully entered into cooperative farming agreements and approved planting of GE crops in eight states without the environmental review required by the National Environmental Policy Act (NEPA) and in violation of FWS policy. This is the third in a series of lawsuits filed by CFS and PEER challenging FWSâ€™s practice of permitting GE crops on wildlife refuges. In 2009 and 2010, the groups successfully challenged approval of GE plantings on two wildlife refuges in Delaware â€” Prime Hook National Wildlife Refuge and Bombay Hook National Wildlife Refuge â€” which forced FWS to end GE planting in the entire 12-state Northeastern region.
In another case involving GE crops, attorneys for CFS, Earthjustice, Beyond Pesticides, and others filed a lawsuit against USDA in March 2011, arguing that the agencyâ€™s unrestricted approval of GE â€śRoundup Readyâ€ť alfalfa violates the Endangered Species Act. USDA announced plans to fully deregulate GE alfalfa in January, despite contamination risks it poses to both organic and conventional farmers.
For more news and information on â€śRoundup Readyâ€ť and other GE crops, see Beyond Pesticidesâ€™ genetic engineering page.