Effect of Nano-Silver on Cell Division and Mitotic Chromosomes: A Prefatory Siren

In vivo cytogenetic assay in Allium root meristems has been carried out to study the effect of nano-silver on cell division and mitotic chromosomes. Nano-silver is a potential anti-bacterial agent recommended as a preservative in personal care and consumer products. Nano particles owing to their size can enter freely into the cells and can interfere in cell's normal function. Studies to justify the safety of nano particles in living systems are inadequate. The present study was planned to understand the possible genotoxic effects of nano-silver in Allium meristems. The germinated onion root tips were treated with different concentrations i.e. 10, 20, 40 and 50 ppm of nano-silver for different time intervals i.e. 0.5, 1, 2 and 4h. The treated root samples exhibited increase in the frequency of chromosomal aberrations and decrease in mitotic index. This is statistically significant at P<0.05 and P<0.001 levels. These abnormalities were observed in a dose and duration dependent manner. The treated meristem cells showed various types of chromosomal and mitotic abnormalities such as fragments, C-metaphase, stickiness, laggard, anaphasic bridge and disturbed anaphase. The present investigation reveals that the nano-silver may cause potential damage to the genetic material and therefore the use of nano-silver in consumer products warrants a detail toxicological investigation to justify its safety.