Exposure to glyphosate, even at very low doses, can, under certain conditions, cause the onset of breast cancer. This is demonstrated by research just published in the scientific journal Frontiers in Genetics, which provides new evidence on the potential carcinogenic action of this substance found in many weedkillers and herbicides.

Glyphosate carcinogenic even at low doses

The study, conducted by a team of researchers from Purdue University in Indiana (USA) and the Institut National de la Santé et de la Recherche Médicale (Inserm) / Institut de Cancérologie de L'Ouest in Nantes (France), revealed that exposure to glyphosate causes a series of changes in the DNA of breast cells that can lead to the onset of a highly aggressive form of cancer.

The study's findings

To carry out their studies, the scientists exposed healthy mammary cells to a low concentration of glyphosate for three weeks, repeating the exposure every three or four days. Initial observation revealed changes at the level of the DNA of breast cells, without this resulting in the onset of cancerous forms. The disease did, however, manifest when the cells were exposed not only to glyphosate but also to certain molecules that are normally present in the human body under conditions of "oxidative stress" caused, for example, by smoking and alcohol, but also by simple ageing.

A highly aggressive form of tumour

In cells exposed to both the herbicide and the substances linked to oxidative stress, the onset of breast cancer was therefore observed, moreover in a particularly aggressive form, as explained by Dr Sophie Lelièvre, one of the study's authors. "The most alarming thing," she commented, "is that we did not observe the typical breast cancer of older women, but the most aggressive form found in younger patients." Glyphosate has long been suspected of having a carcinogenic action in humans, and this study has for the first time observed its role — even at very low doses — in the process of activating breast cancer.