ChEBI: Aristolochic acid is a monocarboxylic acid that is phenanthrene-1-carboxylic acid that is substituted by a methylenedioxy group at the 3,4 positions, by a methoxy group at position 8, and by a nitro group at position 10. It is the most abundant of the aristolochic acids and is found in almost all Aristolochia (birthworts or pipevines) species. It has been tried in a number of treatments for inflammatory disorders, mainly in Chinese and folk medicine. However, there is concern over their use as aristolochic acid is both carcinogenic and nephrotoxic. It has a role as a nephrotoxin, a carcinogenic agent, a mutagen, a toxin and a metabolite. It is a monocarboxylic acid, a C-nitro compound, a cyclic acetal, an organic heterotetracyclic compound and an aromatic ether.