The California Environmental Agency has announced its intentions to have the active ingredient of Roundup—glyphosate—labelled as an agent “known to the state to cause cancer.” In the upcoming months, it will be added to a list of chemicals known to cause cancer, birth defects, and other reproductive harm under the action of Proposition 65. Once this happens, businesses will have to provide “clear and reasonable” warnings before exposing people to Roundup (and other glyphosate products).
Glyphosate goes far beyond Roundup, of course—it’s used in more than 750 different agriculture, forestry, urban, and home products. Further, it’s being used increasingly on genetically modified crops. Ninety-percent of corn and soybean crops were engineered to be resistant to glyphosate, meaning more of the chemical can be used on fields without harming crop yields.
This is potentially problematic, because its widespread use has led to it being detected in air during spraying, in water, in food, and in the blood and urine of agricultural workers—which indicates glyphosate is absorbed and possibly metabolized by humans. Yuck!
Chemical under scrutiny
Many previous studies have given the herbicide a clean report card, but glyphosate has been under a lot of scrutiny as of late. In March, the World Health Organization published a study which lead them to classify the chemical as “probably carcinogenic to humans.” The researchers mainly reviewed studies that examined the effect of glyphosate on rodents—they cited multiple studies in which glyphosate induced various types of cancers in mice and rats, as well as skin tumors in mice.
However, they examined a few human studies as well—several of which linked glyphosate to non-Hodgkin lymphoma. Further, the herbicide was found to induce damage in the DNA and chromosomes of mammals and in human and animal cells in vitro (which generally is how cancers start).
Monsanto, the creator of glyphosate, quickly rebutted the findings of the WHO. “We are outraged with this assessment,” said Dr. Robb Fraley, Monsanto’s Chief Technology Officer, in the Monsanto press release.
“This conclusion is inconsistent with the decades of ongoing comprehensive safety reviews by the leading regulatory authorities around the world that have concluded that all labeled uses of glyphosate are safe for human health. This result was reached by selective ‘cherry picking’ of data and is a clear example of agenda-driven bias.”
But in August, a new collaborative study out of several European universities and Guy’s Hospital in London added more evidence in favor of the WHO’s findings: When rats were administered an ultra-low dose (0.1 parts per billion) of Roundup over the course of two years, many rats experienced kidney and liver damage, and exhibited over 4,000 alterations in the genes of those organs.
For now, California is only labelling glyphosate as a carcinogen instead of restricting or banning it. Environmental groups are celebrating, however, because while it is unclear whether it is harmful to humans, it has decimated monarch butterfly populations.
As glyphosate is so widespread, it has killed an enormous amount of the butterflies’ only food source—milkweed. According to the Center for Biological Diversity, this has led to populations plummeting by 80% over the last 20 years.
Feature Image: Thinkstock