Use of cytological and molecular biological method for water pollution monitoring

Abstract

Allium cepa test is widely used to evaluate the effects of water pollution based on dividing cells since it is a very sensitive tool for prediction and recognition of environmental stresses. This study aimed to evaluate the potential use of A. cepa as a molecular biological indicator to detect the presence of water pollution. A. cepa roots were exposed to water samples at 24 and 48 hours with tap water and hydrogen peroxide solution as controls. The effects of water sample exposure on A. cepa were analysed based on the plant cytotoxicity, genotoxicity, and expression of stress gene between test samples and control sets. The findings showed no significant changes observed in mitotic index of A. cepa exposed to water samples compared to negative control. There is also no expression of alliinase gene was detected. However, there is chromosomal abnormalities observed in A. cepa exposed at 24 and 48 hours. The chromosomal abnormalities detected include lagging chromosome, c-mitosis, disrupted anaphase, disrupted metaphase, spindle disturbance, and stickiness. Our study shows that molecular biological method could be a potential method to serve as an effective, sensitive, and useful marker for water pollution determination.