>Its referring to herbicide-resistant GMO crops where the pesticides are Roundup or Liberty.
Roundup (aka glyphosate) seems to be pretty safe https://en.wikipedia.org/wiki/Glyphosate#Glyphosate_alone
>With regard to Bt, there's a big difference between topical application of Bt and GMO Bt corn (where the Bt is produced inside the plant so bugs are poisoned by the plant).
Why would there be? The wikipedia article I linked mentioned ingestion testing. It's not like they tested bt as a regular spray on pesticide, found it was safe, then approved bt gmo corn without further testing.
>Since the biosphere has a lot of bimolecular pathways its not possible to categorically test everything and catalog all the possible reactions, we just know we can limit the amount of unwanted reactions by using the minimum amount of pesticide. [...] Its an application of the precautionary principle where we act in such a manner to create the least possibility of harm because the scope and extent of the effects are not known.
But the scope and extent of the effects are not known. Glyphosate and bt have both been thoroughly studied. With your "precautionary principle" we'd all be not eating chocolate right now if it was first used as a pesticide (chocolate kills dogs, so if dogs were somehow a pest, it can be used as a pesticide against them).
>They aren't in opposition because mutations don't stop when you start polluting the gene pool with GMO products.
So mutations are intrinsically bad? In other words, if there were some way to stop naturally occurring mutations globally, you'd support it?
>Yes its a problem for the farmers because they can no longer rely on the herbicide to control those competitor organisms, which was the entire point of using a selective herbicide / GMO crop system.
It's a problem, but the alternative (not using any GMO/herbicide) is worst, since the weeds will still be growing out of control. At least if you used GMO/herbicide you have a few decades of weed-free growth.
>With regard to the ecosystem disruption due to pesticide runoff, its an issue for anyone who is dependent on the biosphere because of the harmful effects on biodiversity.
This is totally orthogonal to the discussion of GMOs. If you're worried about pesticide/herbicide run-off from farms, then you'd want to regulate it directly, rather than trying to regulate it by proxy by limiting access to technology that allows for greater pesticide/herbicide use. It's not like the threshold where herbicide levels tolerated by non-gmo crops is the same threshold that ecosystem damage occurs. Not to mention, non-gmo crops can still have their herbicide resistance raised by selective breeding.