There's no way to know for sure. The best option is arguably buying from local producers, who have established reputations for organic operation. But beware of mainstream "organic" designations, because there are huge loopholes.

Also, the truly horrible aspect of this is how persistent these endocrine-disrupting chemicals are, and how they bioaccumulate up the food chain. And not just in the environment, but also in our bodies. In particular, in our fat, given that they're for the most part lipophylic.

Even worse, they're persistent across generations. I recall estimates that, for some compounds, mothers' milk accounts for ~20% of total lifetime exposure. We have indeed been well and truly fucked.