An alarming new study finds that glyphosate, the active ingredient in Roundup weedkiller, is estrogenic and drives breast cancer cell proliferation in the parts-per-trillion range. Does this help explain the massive mammary tumors that the only long term animal feeding study on Roundup and GM corn ever performed recently found?
An alarming new study, accepted for publication in the journal Food and Chemical Toxicology last month, indicates that glyphosate, the world's most widely used herbicide due to its widespread use in genetically engineered agriculture, is capable of driving estrogen receptor mediated breast cancer cell proliferation within the infinitesimal parts per trillion concentration range.[i]
The study, titled, "Glyphosate induces human breast cancer cells growth via estrogen receptors," compared the effect of glyphosate on hormone-dependent and hormone-independent breast cancer cell lines, finding that glyphosate stimulates hormone-dependent cancer cell lines in what the study authors describe as "low and environmentally relevant concentrations."
The results were broken down by the researchers as follows:
- Glyphosate induces T47D, hormone dependent breast cancer cell growth.
- The proliferative effect of glyphosate is mediated via estrogen receptors.
- Glyphosate induces ERE [Estrogen Response Element]-transcription activity via estrogen receptors.
- Glyphosate modulates the expression of E[strogen] R[eceptor] α and E[estrogen] R[eceptor]β in human breast cancer cells.
These effects indicate that glyphosate is a 'xenoestrogen,' capable of inducing Estrogen Response Elements (EREs) in a manner, slightly weaker but functionally similar to the most potent human estrogen Estradiol (E2).
More concerning is the discovery that infinitesimal glyphosate concentrations in the parts-per-trillion rage (10 to the minus 12) had proliferative (carcinogenic) effects on the studied T47D breast cancer cells line:
"In this study, we found that glyphosate at a log interval concentration ranging from 10-12 to 10-6 M increased the cell proliferation of a hormorne dependent breast cancer T47D cell..."
The researchers also discovered that the naturally occurring phytoestrogen in soybean known as genistein, produced "an additive estrogenic effect" when combined with glyphosate, raising the serious question as to whether GMO soybeans are contributing to the epidemic levels of breast cancer within countries like the US where they are consumed in relatively high quantities.
It should be noted that the concentrations used to determine the interactive effects of glyphosate and phytoestrogen genistein in this study were modeled "as in a real world situation" by using information obtained from studies that assayed the respective levels of genistein and glyphosate in GM soybeans, as well as human plasma and urine concentrations following their consumption and/or exposure. For instance, glyphosate concentrations have been detected within human urine within the 0.1 - 233 parts per billion range on the lowest end, and an estimated systemic dose of 0.004 mg/kg on the high end.
The authors stated:
This finding should raise concern about the existence of more than one xenoestrogen such as phytoestrogen and contaminants in plant derived food which may be beneficial or harmful depending on the hormonal and pathological status of consumers. This study implied that the additive effect of glyphosate and genistein in postmenopausal woman may induce cancer cell growth. In this present in vitro study, we showed an estrogenicity of pure glyphosate. In summary, we found that glyphosate exhibited a weaker estrogenic activity than estradiol. Furthermore, this study demonstrated the additive estrogenic effects of glyphosate and genistein which implied that the use of glyphosate-contaminated soybean products as dietary supplements may pose a risk of breast cancer because of their potential additive estrogenicity." [emphasis added]