Degradation of aflatoxin B1 in aqueous medium through UV irradiation

Mutagenesis and cytotoxicity were assessed after exposure to different concentrations of AFB1 and the mixtures of photodegradation products in water (Pw). The Ames test, employing Salmonella typhimurium tester strains TA98 and TA100, was employed to evaluate the residual toxicity of Pw, and the results indicated that the mutagenic activity of UV-treated samples was lower compared with that of untreated samples, but not eliminate absolutely. After exposure of the HepG2 cells to these compounds for different times and concentrations, the cytotoxicity of Pw decreased approximately 40% compared to AFB1, and a small amount of cells were observed dead by the inverted phase-contrast microscope. The results of the Ames and in vitro cytotoxicity assay, providing clues to the assessment of safety issues of UV method applied in AFB1 decontamination, indicate that Pw are less toxic than AFB1, which can be explained by the differences in the chemical nature of the test compounds.