Toxicological Bioassay of Paracetamol Using Allium cepa as a Bioindicator

This study aimed to evaluate the cytotoxic effects of Paracetamol on onion root tip cells. Three experimental treatments were conducted using Paracetamol concentrations of 500, 250, and 125 mg/L, along with a control (distilled water). After 96 hours of exposure, root growth, mitotic index, and the frequency of chromosomal abnormalities in Allium cepa were assessed. The relative growth of the roots of A. cepa was influenced in each treatment, showing a significant decrease from 5.74 0.27 to 1.58 0.13. Microscopic analysis revealed a substantial reduction in the mitotic index, with a recorded value of 8.76 ± 0.7 at the A. cepa 500 mg/L treatment. Furthermore, a total of 10 distinct chromosomal abnormalities were identified, indicating a significant structural impact on chromosomes induced by Paracetamol exposure. The results demonstrate that Allium cepa serves as an effective model for toxicological assessments, as all tested concentrations exhibited significant effects. These findings suggest that prolonged exposure to high Paracetamol concentrations may irreversibly impact genome integrity, posing ecological risks. Further analytical validation and metabolite characterization are essential.