Is the supposed safety advantage of GMO crops over conventional chemical pesticides a mirage?
According to biotech lore, the Bt pesticides introduced into many GMO food crops are natural proteins whose toxic activity extends only to narrow groups of insect species. Therefore, says the industry, these pesticides can all be safely eaten, e.g. by humans.
This is not the interpretation we arrived at after our analysis of the documents accompanying the commercial approval of 23 typical Bt-containing GMO crops, however (see Latham et al., 2017, just published in the journal Biotechnology and Genetic Engineering Reviews).
In our publication, authored along with Madeleine Love and Angelika Hilbeck, of the Swiss Federal Institute of Technology (ETH), we show that commercial GMO Bt toxins differ greatly from their natural precursors. These differences are important. They typically cause GMO Bt proteins to be more toxic. Worse, they also cause them to be active against many more species than natural forms of Bt toxins.
Monsanto, Syngenta, and Dow, are the principal makers of GMO crops intended to kill pests. The vast majority of these GMO insecticidal crops, which include GMO corn, GMO soybeans, and GMO cotton, are engineered to contain a family of protein pesticides called Bt toxins. Such crops may contain up to six different Bt transgenes.
Bt toxins get their name from the bacterial species from which they are originally derived, Bacillus thuringiensis. Biotech seed companies and government officials commonly refer to GMO Bt toxins (which are also called Cry toxins) as “natural”. Commonly also, they state that GMO versions are identical to the Bt toxins …read more