Extracts of Rubiae tinctorum radix have traditionally been used as
treatment for a variety of diseases. Regulatory action has been taken because
insufficient evidence has been gathered about its efficacy. Lucidin (1,2-
dihydroxyanthraquinone), a component of Rubia tinctorum, has been shown in
animal experiments to induce both benign and malignant tumours in the gastric
and intestinal mucosa. Lucidin is positive for the Ames test indicating possible
genotoxicity.