He was using glyphosate as a weed-killer and getting it on his hands and feet. Way higher levels of exposure than any foods. Also if you're afraid of glyphosate, the Roundup-ready crops are the ones to avoid especially - soy, corn, canola, sugar beets. There's no Roundup-ready wheat, oats, or nuts. (edit: apparently it's used as a desiccant so it winds up in cereals as well - lovely, though still there's no evidence it's got dietary effects).

I'm not really concerned about its dietary effects since there's no evidence there, but as an amateur entomologist the effects of Roundup on butterfly populations have been devastating - in the past milkweed was pretty hard to completely weed out by hand, but modern farming can clear hundreds of acres of every trace of milkweed with Roundup/glyphosate.