Is aristolochic acid really the cause of the Balkan endemic nephropathy?

In recent years, aristolochic acid has been promoted vigorously as the causal agent of the Balkan endemic nephropathy because of similarities to some other nephropathies, association with DNA adducts and a perception of human exposure via bread. Critical evaluation of the literature e xposes flaws in these aspects, and there has been consistent failure of experimental toxicology to mimic either the slow silent bilateral atrophy of the Balkan disease or the transitional cell carcinomas in the upper urothelium. It seems yet premature to p romote the curious Balkan disease as aristolochic acid nephropathy without the epidemiological rigour necessary in biomedical research