Unless the bags of them come with the "organically certified" seal there is no way of knowing if any pesticides or herbicides were used on them without knowing the source of the meals prior to packaging.

Alternatively, purchase them from an organically certified source and pay the extra $$.

Dave

Where I buy, the seedmeals (and everything else) are each rated for organic acceptance. That doesn't mean that they were grown organically, but that they are acceptable to use in organic growing situations. If you ever get to Portland, here's a great place:
http://spreadsheets.google.com/pub?key=pJrWEmwyrO76JtBhzIRWDcQ

I'm using a modified version of Steve Solomon's recipes (he has a couple versions). The organic-savvy supplier I went to recommended alfalfa meal - in part because so many seed meals are either not organic or use lots of chemicals or are transported greater distances or are GMOs. I was skeptical at first, in part because of the lower nitrogen rating of alfalfa meal, but since then I've read more and see that alfalfa meal has some great features (a natural growth regulator -- makes a good tea). I simply modified my recipe a bit by adding more alfalfa meal to take into account the lower nitrogen rating.