“A survey of their fields and mills revealed that some of their wheat was indeed contaminated with Aristolochia clematis seed. Back in the lab, Grollman and his colleagues examined kidney samples from Croatian nephropathy patients. They found the same telltale signs of DNA damage linked to Aristolochia clematis as seen in animal studies.”
This sounds like the seed gets mixed in with the harvested wheat and then, when it is milled, the ground-up seed is thoroughly incorporated in the final flour causing the observed problems.
A simple hand weeding process might save thousands of lives.
Yup. when I was 9-10 years old, I was paid a dollar a day to pull 'bitter-weed' out of a dairy farmer's field. It affected the taste of his milk.