Roundup is a chemical herbicide used in industrial agriculture worldwide and sold as a safe product for home garden weed control. It contains 40 percent glyphosate, and the remaining ingredients are listed as "inactive." Recent studies have focused on the toxic health effects of the inactive ingredients. Manufacturers are not required to list individual inactive ingredients on labels. They are considered trade secrets.
Studies until recently have focused on adverse effects of glyphosate. A June 2009 article in Scientific American reports that "in the new study, scientists found that Roundup's inert ingredients amplified the toxic effect on human cells---even at concentrations much more diluted than those used on farms and lawns." The inactive ingredients were found to damage human cells, especially those in the placenta and umbilical cords.
Roundup was approved by the U.S. Environmental Protection Agency as a Group E chemical, which means that evidence shows no relationship to cancer. Studies at the University of Caen in France were conducted on both the main ingredient, glyphosate, and the inactive ingredient chemicals. These studies showed a link between reproductive cancer and Roundup's toxic inactive ingredients.
Effect on People
An Ontario, Canada, study showed that exposure of male farm workers to Roundup was associated with increased incidence of miscarriage and premature birth in their wives. Higher incidents of birth defects and cancers have also been reported in people living near crop-spraying areas in Argentina. Less severe symptoms reported from exposure to Roundup include headaches, eye soreness, diarrhea, facial numbness, blisters, rapid heart rate and chest pains.
Effect on Soil
"Residues of glyphosate have been known to persist for months in anaerobic soils deficient in microorganisms," according to Beyond Pesticides. The International Organization for Biological Control reported that Roundup killed over 50 percent of beneficial insects and affected the growth and survival of earthworms. Earthworms are vital to soil fertility and the soil "foodweb."
The EPA tests products to ensure that people are safe if they use it according to the label. One of the warnings on Roundup is that it should not be used near or in fresh water, to protect amphibians and other wildlife. Genetic malformations have been found in amphibians exposed to Roundup that has drifted in the air or water. "Inert ingredients" on pesticide and herbicide labels does not mean they are harmless.