Anthony Samsel and the activist group Moms Across America have suggested recently that glyphosate is found in vaccines. Nothing from Anthony Samsel’s results provides reliable evidence that glyphosate is present in vaccines. Everything that regulatory agencies and credible scientists know about glyphosate tells us this outcome is extremely unlikely. Unfortunately, such sensational allegations only serve to spark unwarranted fear and confusion and make finding reliable information much more difficult. In this post, I will discuss how this accusation is not credible by looking into the science behind the testing method.

Anthony Samsel has not published in a reputable, peer-reviewed journal any detail about what he or others did, so I can only comment based on incomplete and vague information.  Usually, I refrain from commenting on articles that haven’t been published in peer-reviewed journals, because that is the gold standard for the scientific community. If someone publishes science, reviewed by your peers, it carries weight; it deserves my attention to learn more about the science. However, Samsel’s study is not published in a peer-reviewed journal. I’m making an exception here, because it is irresponsible to scare parents about a matter as critical as children’s vaccinations.

It’s important to understand the background of the testing method used by Anthony Samsel, whose other claims have been rebutted elsewhere (“Medical Doctors weigh in on Glyphosate Claims” and “Condemning Monsanto With Bad Science Is Dumb”). The testing method used here for vaccines appears to be a method that was developed as a quick and inexpensive screening test for water samples to decide whether additional testing with a more expensive and precise method is needed. Simply put, because of this method’s potential for false positives at very low concentrations, a negative result of the test on water means no further testing is required; a positive result means one should conduct the more expensive test to confirm. This quick and inexpensive screening test has only been shown to work well in water – not vaccines, not wine, not beer, not milk, not eggs. Just water.

The activist group Moms Across America, the same group now helping promote Anthony Samsel’s vaccine allegations, previously used this quick and inexpensive testing method to incorrectly claim the detection of glyphosate residues in breast milk. After Moms Across America claimed to find glyphosate residues in breast milk using this method, a professor at Washington State University, Dr. Michelle McGuire, led a study to collect and analyze different samples using a more precise and validated method. Dr. McGuire found no glyphosate residues in breast milk. A previous study from New Zealand, a subsequent study in the United States and two subsequent studies from Germany also found no evidence of glyphosate residues in milk, and all of these studies reported an extensive validation of the assays.

Similarly, the method used by Anthony Samsel to generate data on vaccines was recently used to claim that glyphosate is present in eggs. Subsequent testing by the Food and Drug Administration, again using a valid method, did not detect glyphosate in eggs. Together, these results indicate that the quick and inexpensive test used to generate data on glyphosate in vaccines has been pushed beyond its reliable limits. One can only speculate that the motive here is to provoke fear and concern where none reasonably exists.

Glyphosate is a weed killer that inhibits a pathway found in plants, but not in humans or animals. Glyphosate is not a carcinogen, and it has a 40-year history of safe use. Like any weed killer, glyphosate has been extensively reviewed and approved for use by the U.S. EPA and other global regulatory authorities. For more information, please visit

Originally published September 13, 2016 by Wes Matthews