Occurrence of emodin, chrysophanol and physcion in vegetables, herbs and liquors. Genotoxicity and anti-genotoxicity of the anthraquinones and of thewhole plants

1,8-Dihydroxyanthraquinones, present in laxatives, fungi imperfecti, Chines e herbs and possibly vegetables, are in debate as human carcinogens. We scr eened a variety of vegetables (cabbage lettuce, beans, peas), some herbs an d herbal-flavoured liquors for their content of the 'free' anthraquinones e modin, chrysophanol and physcion. For qualitative and quantitative analysis , reversed-phase HPLC (RP-LC), gas chromatography-mass spectrometry (GC-MS) and RP-LC-MS were used. The vegetables showed a large batch-to-batch varia bility, from 0.04 to 3.6, 5.9 and 36 mg total anthraquinone per kg fresh we ight in peas, cabbage lettuce, and beans, respectively. Physcion predominat ed in all vegetables. In the herbs grape vine leaves, couch grass root and plantain herb, anthraquinones were above the limit of detection. Contents r anged below 1 mg/kg (dry weight). Ail three anthraquinones were also found in seven of 11 herbal-flavoured liquors, in a range of 0.05 mg/kg to 7.6 mg /kg. The genotoxicity of the analysed anthraquinones was investigated in th e comet assay, the micronucleus test and the mutation assay in mouse lympho ma L5178Y tk(+/-) cells. Emodin was genotoxic, whereas chrysophanol and phy scion showed no effects. Complete vegetable extract on its own did not show any effect in the micronucleus test. A lettuce extract completely abolishe d the induction of micronuclei by the genotoxic anthraquinone danthron. Tak ing into consideration the measured concentrations of anthraquinones, estim ated daily intakes, the genotoxic potency, as well as protective effects of the food matrix, the analysed constituents do not represent a high priorit y genotoxic risk in a balanced human diet. (C) 1999 Elsevier Science Ltd. A ll rights reserved.