Abstract

Chlorophenols are compounds used as intermediaries in manufacturing agricultural pesticides. Despite the efficiency on their targets, they are considered as environmental pollutant substances. This study assessed two chlorophenol substances, 2-chlorophenol and 2,4-dichlorophenol (2-CP, 2,4-DCP) for their cytogenetic, genotoxic, and nucleic acid content affects using Allium cepa and Vicia faba assay. In A cepa, 2-CP low dosages (0.625%) increased the mitotic index (MI), while high dosages (1.25 and 2.5%) decreased it; the high dosage (2.5%) increased the chromosomal aberration frequency (CAF). Treatment with 2,4-DCP showed that 2.6% was the most affected treatment, it decreased MI and increased CAF. In V. faba, both 2-CP and 2,4-DCP decreased MI and increased CAF. Types of chromosome anomalies scored after treatment with different concentrations were chromosome stickiness, disturbance, lagging chromosomes, anaphase and telophase bridge, and micronuclei. The contents of DNA and RNA in A. cepa were increased by 2-CP and 2,4-DCP, and decreased by the half dosage of 2-CP (1.25%); the RNA content varied directly proportional to DNA, while in V. faba, all tested concentrations of chlorophenols increased nucleic acids contents, and 1.3% was significantly affected.  The results showed that the two substances have cytogenetic, genotoxic impact, and also have influence on the nucleic acid contents in both plants.

Key words: Cytogenetic, genotoxic, chlorophenols, Allium cepa, Vicia faba.