RODALE NEWS, EMMAUS, PA—The scientific evidence piling up against Roundup, the best-selling weed killer for home and farm use, is starting to sound a bit sci-fi. The latest damaging evidence against this potent herbicide, once widely believed to be safe, comes from the United States Geological Survey (USGS), which is now detecting glyphosate, the active ingredient in Roundup, in streams, the air, and even rain.
While the concentrations detected in rain and air are thousands of times less than what farmers dump onto field crops, emerging scientific evidence about what these chronic low-level exposures do to our bodies is cause for major concern, particularly among unborn babies and young children. These tiny amounts we're breathing in daily could be altering our hormones and wreaking all sorts of havoc on our bodies, but the human health effects may not show up for years or decades. "We don't fully know what our results mean," says study author Paul Capel, PhD, environmental chemist at USGS. "If we go out to the streams or air, we see it. There's a broader off-field exposure. The significance of that, I don't think we really know."
Pesticide-exposure expert Warren Porter, PhD, professor of environmental toxicity and zoology at the University of Wisconsin, Madison, did the math. He took the air exposure numbers from the USGS study and found some reason for concern. His calculations showed that the levels found in the USGS survey could lead to accumulated levels that could alter endocrine mediated biochemical pathways, leading to obesity, heart problems, circulation problems, and diabetes. Low-level exposure to hormone disruptors like glyphosate (Roundup's main ingredient) has also been linked to weakened immune function and learning disabilities. "This study is just looking at a single day of exposure," he says. "If you consider that our body hormones work in the parts per trillion and you disrupt normal endocrine function, which tends to alter biochemical pathways, you may be flipping biological switches that have long-term impacts. No one has explored whether Roundup has epigenetic impacts which alter gene expression, possibly for a lifetime."
So why the influx of Roundup in the air? Easy. The majority of corn, cotton, canola, and soy crops grown in the United States are genetically engineered to tolerate heavy dousings of Roundup. Interestingly, the same company, Monsanto, developed both the pesticide and the genetically engineered seed created to handle that pesticide—they're sold together as a package. When we eat those crops (or when they're turned into ingredients used in processed foods), we wind up eating the Roundup, too. Roundup is actually taken up inside of food that we eat, so not only are we breathing it in and getting soaked in it when it rains, but we're also eating it at dinnertime.