Cottonwolf's picture
Can you comment on these studies listed on a web site called 5 reasons to be concerned about GMOs? While Monsanto initially marketed Roundup as being safer than table salt, several studies have pointed to health risks. A 2008 study in Sweden linked Roundup exposure to nonHodgkins lymphoma. A 2007 study in Ecuador found a higher degree of DNA damage in a population that had been aerially sprayed.

A:Expert Answer

I'm glad to comment on these points. First, look at the dates. These are results, almost a decade old, that nobody else has repeated. Think about it. In science, everyone wants to be number two! If these results were real, they would have opened new worlds of inquiry with many labs and hundreds of papers.
When we talk about Roundup, we need to consider two things: toxicity and exposure. First, let's talk exposure. It is applied weeks before there is product on the plant, so even plants with “high” levels have very little (like, 20 ppm at worst). We understand how the active ingredient, glyphosate, behaves in the human body. Bottom line: you'd have to drink the concentrate, or eat thousands of kilograms of soybeans, to get a biologically meaningful dose.
Let's talk about the published reports.
The one from Ecuador is a real mess, which is a little sad, because the lead author is usually pretty solid. If you take the time to read the paper, the problems become apparent. First, the people surveyed live in homes that are near the fields and were given a 20x-acceptable rate of exposure. That's not good.
Secondly, the comparison group and the exposed group were surveyed and processed separately, and a DNA-degradation assay was used. The two groups were far apart, too. Basically, the scientists compared apples to oranges. It just is not a great study, and the authors (to their credit) even say that. They freely acknowledge the shortcomings of the report, which anti-GM folks seem to ignore.
The Swedish work comes from Eriksson et al. who have a decade of herbicide-associated cancer claims. Their work is done by surveys and simply associates potential exposure to disease incidence. There are no tests to determine if the cancer victims even were exposed. It is cute associations at best, and the authors (again to their credit) recognize that the associations are not proven to be causal.
In both of these cases, the anti-GMs actually extrapolate and hyperbolize the results of two reports, each of which has severe limitations.
Again, the best evidence that these foundations are shaky is that nobody, even the same groups, followed these lines of study. Thanks for the question, and contact me anytime.