Table 3. Micronucleated binucleated cells (MNBNs) frequency in Caco-2 cells following exposure to fumed or precipitated SiO2 particles

Treatment Concentration (µg/mL) S9 mix MNBN (%)
Control 0 - 2.0
Positive control (MMS) 25 6.5
Fumed SiO2 1,000 2.0
Precipitated SiO2 1,000 2.5
Control 0 + 1.5
Positive control (CPA) 10 7.0
Fumed SiO2 1,000 1.5
Precipitated SiO2 1,000 1.0
MMS, methyl methanesulfonate; CPA, cyclophosphamide; -, without; +, with.