This study demonstrated the sensitivity of the Vicia faba MN test
to evaluate genetic alterations due to sewage sludge contaminated
with hexavalent chromium. The MN test was used to assess the
impacts of the sewage sludge co-composted products by testing
two approaches. The results revealed that aqueous extract
approach is suitable to assess the genotoxic potential of cocomposted
substrates of different sludge mixtures contaminated
with hexavalent chromium. The Vicia faba tests in aqueous extracts
performed in this study, have also confirmed the potential of cocomposting
aerobic process to remove Cr toxicity and genotoxicity
by reduction of Cr(VI) of sludge with an abatement rate of around
58% after six months. This method seems sensitive and reproducible
over a wide range of pollutant concentrations and risk
assessment especially of water-extractable pollutants.