Aristolochia weeds cause of mysterious Balkan disease

Scientists speculate that the highest risk factor for a kidney disease common to five Balkan nations is a plant commonly used in various Chinese herbal medicines. First described in Bulgaria in the scientific literature in the 1950s, Balkan Endemic Nephropathy (BEN) caused individuals, usually aged in their 50s, to develop symptoms of uremia, a buildup of nitrogenous waste products in the blood that signal renal failure. The irreversible renal disease would lead to death. Certain villages have a high BEN prevalence, but other villages only a few kilometers apart may be unaffected.

http://www.sciencedaily.com/releases/2014/09/140930111421.htm

"The toxicological and epidemiological evidence linking AA (aristolochic acid ) with BEN are convincing in terms of the strength of association, consistency, specificity, temporality, dose-response relationship, coherence, experiment, and analogy," the authors state,