Humic acids from compost in antimutagenesis processes in soil

The antimutagenic activity of the three humic acids extracted from composts of different origin (solid urban wastes, tomato industry residues and olive mill pomace) was assayed by the micronuclei test and the aberrant anatelophase assays in Vicia faba meristem cells. Humic acids, added to Vicia faba seedlings in concentrations of 50 and 200 mg L-1 before their contact with maleic hydrazide (MH), showed a protective activity against the genotoxic damages induced by the herbicide. Several xenobiotics in composts may, therefore, have different effects on the induction of micronucleated cells, when composts or humic acids extracted from them were used.