Friday, April 24, 2015

Are glyphosate tolerance levels headed in the wrong direction?

The month of March 2014 was a troublesome one for glyphosate. First, the World Health Organization (WHO) declared glyphosate “probably carcinogenic to humans” based on the unanimous recommendation of 17 experts representing 11 countries. Shortly thereafter, a study published by The American Society for Microbiology (ASM), in its peer reviewed journal mBio, linked glyphosate to antibiotic resistance. In addition to these two science-based findings, a viral video surfaced showing a man wrongly identified as an industry lobbyist refusing to drink Round Up after he claimed it was safe to drink.

The WHO based its declaration on three primary findings: (1) cancer in mice and rats that consumed glyphosate over a several year period, (2) mechanistic and cellular studies that provided “strong” evidence of how glyphosate may cause cancer, and (3) epidemiological evidence, primarily from glyphosate applicators and farmworkers. The ASM study examined the sublethal effects of various herbicides on microbes. Unlike previous studies that examined the lethal effect of herbicides, such as whether they kill an organism, the new study looked at the impact of glyphosate on the organism when it stays alive.

While the Environmental Protection Agency (EPA) is currently reviewing Roundup as part of its regular 15 year review process, that is not the agency’s only recent action on glyphosate. In May of 2013 the EPA approved an increase in pesticide tolerance limits for glyphosate on certain crops. Although the petitioner Monsanto did not get an increase on all the limits they asked for, the EPA did double the tolerance level for soybeans, America’s second largest crop. Even though much of the data relied on in the WHO declaration existed at the time the EPA made its decision to increase tolerances, the EPA is not required to consider all the factors relied on by the WHO. For instance, the EPA does not have to consider occupational exposure to glyphosate, whereas occupational exposure is one of the three primary supports for the WHO’s position. Of course, tolerance levels may ultimately mean very little since the U.S. does not test produce for glyphosate residue.

Because antibiotic resistance is one of the world’s most pressing health problems and doctors will diagnose almost 1.7 million Americans with cancer while over a half-million Americans die from cancer in 2015, one has to wonder if increased glyphosate use is what society needs right now. The amount of glyphosate used in the United States increased ten-fold between 1996 and 2011 and continues to grow. The rise of superweeds coupled with increased tolerance levels will encourage farmers to use more glyphosate.

The EPA review process includes focus meetings, an assessment of changes since the pesticides last review, new assessments if needed, a public comment period, and consultation with other government agencies. Before the agency issues its final decision, it issues a proposed decision and allows the public at least 60 days to comment. The EPA recently said that it may recommend the USDA begin testing for glyphosate residues. Given recent announcements that question the safety of glyphosate and the fact that the EPA does not have to consider all available evidence regarding safety, it will be important for consumers to look for the EPA's proposed decision and comment accordingly.

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