Claims of Glyphosate and its link to Autism

There is a LOT of misinformation about autism on the internet. Everything from vaccines to wi-fi  has been said to cause autism. So when a new study comes out saying that scientists have found that something new has been found to cause autism, I am extremely skeptical.

One of the newer claims is that glyphosate, an herbicide used on pesticide-resistant crops causes autism, I was not immediately convinced. First off, people like Dr. Mercola support this claim, and if I have learned anything, Mercola tends to support research findings before the findings are conclusive. So, when I found out that he also supported this idea,  I decided to see where it came from.

This took me on a webpage journey across many pages, in search of the original study. After clicking through tens of circular paths between sites such as naturalnews and reset.me, I decided to go to Snopes to find the original study. Unfortunately, the closest thing I found was a dead link. Perhaps this is why I couldn’t find it. If Snopes’ link was dead, no wonder I couldn’t find it. Eventually, I did actually find the study, but their main evidence seemed to be correlations between glyphosate usage and various diseases. A correlation is not good evidence for causation. This fun website shows users how many unrelated things can correlate, and even allows users to correlate anything they want. In a minute of playing around, I “found” a correlation that was more correlative than their findings. My finding was 99.78% correlative, and theirs was only 98.5% correlative. Clearly, it is ridiculous to suggest that the sales of General Mills and females in California who slipped or tripped to their death have any sort of causal relationship, and yet the correlative relationship is there. Considering this seems to be their only evidence, I have a hard time understanding how this is an accepted finding by anyone.

This poking fun at the correlation is not to say that there is nothing to this idea. It simply means that there should first be some potential for biological interactions, and then further research can be done. If there is not a possibility for any biological interaction, then there is not a good reason to spend valuable research money on a study that is likely to show no positive result. If there was an unlimited amount of money available for research, then this would be a good thing to research, but scientists must find the best use of the funds available, and that means finding a good reason for the research to be done before it is done.

Looking for a real, biological link, I skimmed the paper, searching for the term glyphosate. There are real mechanisms identified, which I give credit to the authors for finding. However, the evidence used relies on studies showing lethality of the chemical. The problem is that everything is a chemical, and chemicals, including water, can be toxic in very high concentration. Just showing that a chemical can be toxic at high concentrations does not prove that there is any risk for the average consumer. Interestingly, the LD50 (the amount at which a given substance kills 50% of rats in a population) for caffeine is lower than glyphosate (200mg/kg for caffeine and 5,600mg/kg for glyphosate). That means that caffeine can kill rats at a lower dose than glyphosate can. This doesn’t prove anything about its toxicity, but it certainly suggests questions about how safe glyphosate truly is for mammals.

An important part of reading and understanding studies is seeing if the author is qualified to examine evidence about a certain subject. Dr. Stephanie Seneff, the original author of the study is a computer scientist at MIT. This does not qualify her to write papers about biology. The other author, Anthony Samsel, has apparently worked as a consultant, and again, this does not qualify him for this discovery. That being said, it is not to say that they could not have possibly found a link; it just means that their discoveries would need a high degree of evidence. As Carl Sagan said, “Extraordinary claims require extraordinary evidence,” and this is especially true then the claimants are not qualified to make their claims.

In summary, it is not strictly impossible that glyphosate causes autism, or medical problems. However, there needs to be a considerable amount of evidence to make a claim such as this, but with the current evidence, it is nothing short of irresponsible to make these claims.

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