Initially, your position seems to be that since everything is chemicals, then chemicals are safe to eat.
But then you go on to say that in nature, some things are poisonous, even though they're also chemical like all others things.
So? We've evolved alongside certain things that we ate, like free-range organic chicken eggs, for instance. We evolved to eat them. Who knows what happens when you raise those chickens in boxes that don't allow them to move, feed them feed they didn't evolve to eat, and douse them with antibiotics? What's the result or such treatment: a chemical poison or a chemical food?
That's why we do testing. But still, long-term effects are hard to measure. Things we used to think were not poisonous were later discovered to be so.
So I think the less we meddle with food (i.e. the more organic it is), the less chances there are that things might go wrong. It's like a machine: the more parts it has, and the more you fiddle with it, chances increase that something will go wrong.
What do you think?
Actually toxicity depends on the dose. The initial explanation about 'everything is a chemical' was to address chemophobia. My point is if we have control over the chemicals that we consume, it is perfectly alright.
We always meddled with the food; that's how we got high yielding crops, well producing animals etc. We nurtured whatsoever we found good. Almost all the fruits were less sweet and tasty. We overgrew the better ones that gave pleasure to our taste buds. As a result, now those species dominate over the lesser tasty ones.
We have to continue meddling with the food. Otherwise availing nutritious food for the ever exploding population would be extremely difficult.
Another solution of course would be to have no more than 1 child for every 1 person (i.e. 2 per couple), but that I guess is too radical.
Of course that would mean that the economy would collapse because older people are living longer, which would necessitate the discovery of scientific immortality to enable everyone to work, but that's a whole other issue.