bt again

On the one hand, researchers have clear evidence that viral/parasitical genes can infiltrate our genome, and even become part of what we pass on to our children, on the other, they firmly state that the bt genes will not escape into the wild fauna/other crops nearby. This kind of blinkered approach does not make good science. The proponents of bt technology pooh-pooh concerns about the gene escaping . We do not know that it won't. Nor do we know how it will be manifested once it infiltrates other genomes, ....maybe the crop of wheat grown next to bt crop will acquire the bt gene and in that, it may produce toxins in the seeds (can you imagine acres of poisoned wheat?). We really do not know and this is a risk we should not have taken even with cotton. The risk is too huge...once a gene is in the wild, we have no control over what it infiltrates and how it will get manifested in other species.
Why is it unscientific to have these concerns?