Monsanto has used the gene from Bacillus thuringiensis (Bt) to genetically modify certain crops to be Bt resistant. Bacillus thuringiensis produces BT-toxin. It’s a pesticide; and it breaks open the stomach of certain insects and kills them.
The new study reveals that the Bt toxins Cry1Aa, Cry1Ab, Cry1Ac or Cry2A have toxic effects in the blood of mice and that the claims by policy regulators of the presumed nontoxicity of Bt toxin to mammals, on which all regulatory approvals of Bt crops are based, is false.
The mechanism of operation of BT toxin on insects (the target population for the pesticide) is to break holes in the gut and rupture cells. In mice in this experiment Bt toxins, caused red blood cells to rupture and is highly disconcerting as BT toxin has crossed the placenta and was found in the umbilical cord in over eighty percent of mothers tested suggesting that it crosses into the blood stream of babies.
The study authors stated: “It has been reported that Cry toxins exert their toxicity when activated at alkaline pH of the digestive tract of susceptible larvae, and, because the physiology of the mammalian digestive system does not allow their activation, and no known specific receptors in mammalian intestinal cells have been reported, the toxicity [of] these MCAs [microbial control agents] to mammals would negligible. However, our study demonstrated that Bt spore-crystals genetically modified to express individually Cry1Aa, Cry1Ab, Cry1Ac or Cry2A induced hematotoxicity, particularly to the erythroid lineage. This finding corroborates literature that demonstrated that alkali-solubilized Bt spore-crystals caused in vitro hemolysis in cell lines of rat, mouse, sheep, horse, and human erythrocytes and suggested that the plasma membrane of susceptible cells (erythrocytes, in this case) may be the primary target for these toxins”.
” In conclusion, results showed that the Bt spore-crystals genetically modified to express individually Cry1Aa, Cry1Ab, Cry1Ac or Cry2A can cause some hematological risks to vertebrates, increasing their toxic effects with long-term exposure. Taking into account the increased risk of human and animal exposures to significant levels of these toxins, especially through diet, our results suggest that further studies are required to clarify the mechanism involved in the hematotoxicity found in mice, and to establish the toxicological risks to non-target organisms, especially mammals, before concluding that these microbiological control agents are safe for mammals.”
The toxicity of Bt proteins in mammalian cells was also the subject of an in vitro (test-tube) study (Mesnage et al., 2012; http://onlinelibrary.wiley.com/doi/10.1002/jat.2712/abstract). In this study, Bt toxin Cry1Ac was found to be substantially toxic to human cells, raising substantial concerns in the human population.
Mezzomo, B. P., et al. (2013). Hematotoxicity of Bacillus thuringiensis as spore-crystal strains Cry1Aa, Cry1Ab, Cry1Ac or Cry2Aa in Swiss albino mice. J Hematol Thromb Dis 1(1). http://dx.doi.org/10.4172/jhtd.1000104