This is going to be different country to country, but organic farming can still use pesticides. I posted a link below as well, but organic farming is also not conclusively better for the environment. It has lower yields, and therefore requires more land. You have to balance the effects of converting more land into organic farmland versus the benefit of, for example, less fertilizer runoff.

At the end of the day, "organic" is a marketing term, not a statement of health or ecological benefit. Most complaints about conventional agriculture (and GMOs) are actually complaints about industrialized agriculture as a whole.

I wish there was a good, regulated term for food that was produced with the best known processes (and perhaps there is for specific foods), but "organic" is not it.