But we all know that Rattlesnake venom is 100% organic and all natural. So I'm personally not sure if the distinction between "synthetic" and "organic" is very appropriate. Nature can certainly mass-produce poisons that can be detrimental to humans.
The Pesticide problem is rather simple: we want to spray a poison onto our plants that kills insects, but doesn't harm humans (or the plants). Whether you use an "organic" pesticide or "synthetic" one, the fact remains that you are consistently spraying poisons. And these poisons haven't been very well tested for long-term low-level exposure levels. Be it organic or synthetic.