Glyphosate, pathways to modern diseases III: Manganese, neurological diseases, and associated pathologies
| Introduction |
Glyphosate is the active ingredient in Roundup®, the most widely used herbicide on the planet. [314] Glyphosate enjoys widespread usage on core food crops, in large part because of its perceived nontoxicity to humans. The adoption of genetically engineered “Roundup ® -Ready” corn, soy, canola, cotton, alfalfa, and sugar beets has made it relatively easy to control weeds without killing the crop plant, but this means that glyphosate will be present as a residue in derived foods. Unfortunately, weeds among GM Roundup ® -Ready crops are developing ever-increasing resistance to Roundup ® , [107],[221] which requires an increased rate of herbicide application. [26] In 1987, glyphosate was the 17 th most commonly used herbicide in the United States, but, in large part due to the introduction of glyphosate-resistant core crops, it became the number one herbicide by 2001.[146] Its usage has increased steadily since then, in step with the rise in autism rates. Glyphosate’s perceived nontoxicity is predicated on the assumption that our cells do not possess the shikimate pathway, the biological pathway in plants, which is disrupted by glyphosate, and whose disruption is believed to be the most important factor in its toxicity.
It may seem implausible that glyphosate could be toxic to humans, given the fact that government regulators appear nonchalant about steadily increasing residue limits, and that the levels in food and water are rarely monitored by government agencies, presumably due to lack of concern. However, a paper by Antoniou et al. [12] provided a scathing indictment of the European regulatory process regarding glyphosate’s toxicity, focusing on potential teratogenic effects. They identified several key factors leading to a tendency to overlook potential toxic effects. These include using animal studies that are too short or have too few animals to achieve statistical significance, disregarding in vitro studies or studies with exposures that are higher than what is expected to be realistically present in food, and discarding studies that examine the effects of glyphosate formulations rather than pure glyphosate, even though formulations are a more realistic model of the natural setting and are often orders of magnitude more toxic than the active ingredient in pesticides. [189] Regulators also seemed unaware that chemicals that act as endocrine disruptors (such as glyphosate [108] ) often have an inverted dose-response relationship, wherein very low doses can have more acute effects than higher doses. Teratogenic effects have been demonstrated in human cell lines. [212] An in vitrostudy showed that glyphosate in parts per trillion can induce human breast cancer cell proliferation. [289]
Adjuvants in pesticides are synergistically toxic with the active ingredient. Mesnage et al. [189] showed that Roundup ® was 125 times more toxic than glyphosate by itself. These authors wrote: “Despite its relatively benign reputation, Roundup ® was among the most toxic herbicides and insecticides tested.” [189]
The industry dictates that 3 months is a sufficiently long time to test for toxicity in rodent studies, and as a consequence none of the industry studies have run for longer than 3 months. The only study we are aware of that was a realistic assessment of the long-term effects of GM Roundup ® -Ready corn and soy feed on mammals was the study by Séralini et al. that examined the effects on rats fed these foods for their entire life span. [261] This study showed increased risk to mammary tumors in females, as well as kidney and liver damage in the males, and a shortened lifespan in both females and males. These effects occurred both in response to Roundup and to the GM food alone. These effects only began to be apparent after 4 months.