Glyphosate bonds with lipids to create a highly reactive phospholipid analog of lecithin that crosses both the blood brain barrier and the placental barrier in higher lifeforms.

Expert response from Akbar Mehrsheikh, Ph.D.

Lead Scientist, Bayer Crop Science

Thursday, 15/10/2015 13:39

Thank you for that scary sounding question. I wish you had said where you read that because there are lots of unfounded claims out on the internet and they are easiest to respond to with the details of the claim. But this one is probably easy to answer since no such reaction, as described, has ever been noted or studied and it is inconsistent with the fundamental chemical properties of these molecules. I can speculate, however, that the source of this confusion is simply a misunderstanding between the chemical terms “phosphonate” and “phosphate”. 

The structure of common plant/animal phospholipids (a major molecule in all cell membranes) consists of a one glycerol molecule, two fatty acids and a phosphate. The attachment between the glycerol and the other three molecules is via ester bonds and the result is a phospholipid. The phosphorous atom in glyphosate is not in the form of a phosphate ester but rather it belongs to the “phosphonate” (or “phosphonic acid”) class of chemistry. The phosphonate nomenclature is for compounds with a central phosphorous bonded to three oxygen atoms and a single carbon. Phosphates have a central phosphorous bonded to 4 oxygen atoms. The two families of compounds (i.e. phosphates and phosphonates) represent completely different chemistries and physiochemical properties. 

Phosphonates occur naturally in a few marine organisms but otherwise are very rare. Phosphates are a major component of virtually all major metabolic processes in plants, and animals. However, glyphosate is not naturally occurring and only interacts with one enzyme which is found only in plants and microbes specifically, EPSPS (an enzyme named 5-EnolyPyruvyl Shikimate 3 Phosphate Synthase). Glyphosate is an ionic, water soluble molecule and does not interact with membranes or lipids. Glyphosate cannot by itself react with anything except highly reactive molecules, which can react with everything else too. We and many others have never detected any phospholipids analogs of glyphosate in numerous plant/animal metabolism studies that have been conducted using the extremely sensitive techniques with ¹⁴C radiolabeled glyphosate in the past 45 years required by global regulatory agencies.  To our knowledge, there are no examples of reactions of glyphosate with lipids in peer-reviewed scientific journals.  

Expert response from Akbar Mehrsheikh, Ph.D.

Lead Scientist, Bayer Crop Science

Thursday, 15/10/2015 13:39

Thank you for that scary sounding question. I wish you had said where you read that because there are lots of unfounded claims out on the internet and they are easiest to respond to with the details of the claim. But this one is probably easy to answer since no such reaction, as described, has ever been noted or studied and it is inconsistent with the fundamental chemical properties of these molecules. I can speculate, however, that the source of this confusion is simply a misunderstanding between the chemical terms “phosphonate” and “phosphate”. 

The structure of common plant/animal phospholipids (a major molecule in all cell membranes) consists of a one glycerol molecule, two fatty acids and a phosphate. The attachment between the glycerol and the other three molecules is via ester bonds and the result is a phospholipid. The phosphorous atom in glyphosate is not in the form of a phosphate ester but rather it belongs to the “phosphonate” (or “phosphonic acid”) class of chemistry. The phosphonate nomenclature is for compounds with a central phosphorous bonded to three oxygen atoms and a single carbon. Phosphates have a central phosphorous bonded to 4 oxygen atoms. The two families of compounds (i.e. phosphates and phosphonates) represent completely different chemistries and physiochemical properties. 

Phosphonates occur naturally in a few marine organisms but otherwise are very rare. Phosphates are a major component of virtually all major metabolic processes in plants, and animals. However, glyphosate is not naturally occurring and only interacts with one enzyme which is found only in plants and microbes specifically, EPSPS (an enzyme named 5-EnolyPyruvyl Shikimate 3 Phosphate Synthase). Glyphosate is an ionic, water soluble molecule and does not interact with membranes or lipids. Glyphosate cannot by itself react with anything except highly reactive molecules, which can react with everything else too. We and many others have never detected any phospholipids analogs of glyphosate in numerous plant/animal metabolism studies that have been conducted using the extremely sensitive techniques with ¹⁴C radiolabeled glyphosate in the past 45 years required by global regulatory agencies.  To our knowledge, there are no examples of reactions of glyphosate with lipids in peer-reviewed scientific journals.