GENTECH archive


Re: Bt toxic also for human ?

> It seems that Bt could be toxic (at least in a bacteria) also
> to humans.
> Yet it has been said for a long while (and it is currently repeated by biotechs)
> that Bt is safe to humans !

Carefully reading the document included in your mail, I observed 
two paragraphs of interest. These two paragraphs suggest that the 
insecticidal Cry protein is not involved in pathogenicity (to humans).

> >Francoise Ramisse of le Bouchet and her colleagues found that healthy mice
> >inhaling 108 spores of Bt H34 died within eight hours from internal
> >bleeding and tissue damage. Spores from mutants of the same strain which
> >did not produce the insecticide were equally lethal to mice, suggesting
> >that it was not to blame.

> >The researchers think that the symptoms are caused by other toxins. The
> >bacterium's close cousin, Bacillus cereus, produces a toxin that ruptures
> >cell membranes. And in 1991, Japanese researchers showed that B.
> >thuringiensis produces the same toxin.