A high-fibre diet is supposed to help, as fibre can absorb toxins. To what extent I don't know. So, make your own sourdough wholewheat bread. And eat plenty of greens like broccoli, cabbage . I guess the greens are sprayed with stuff too though. As is the wheat in the bread. The fibre might counteract the effects of the sprays somewhat.
Greens I believe absorb more heavy metals.
Haven't some studies found that donating plasma helps scrub your blood?