ANGELA TOCHUKWU NWEKE

This study assessed DNA damage in commercial drivers exposed to vehicular emissions at the University of Benin (UNIBEN) Main Gate, Benin City, using the micronucleus assay of buccal cells. Vehicular emissions are a major source of air pollution containing genotoxic substances such as polycyclic aromatic hydrocarbons, nitrogen oxides, and particulate matter, which can induce chromosomal damage. A comparative cross-sectional design was used, involving 25 exposed drivers and 9 non-exposed controls. Buccal epithelial cells were collected using sterile wooden spatulas, fixed in Carnoy’s reagent, and stained with May-Grünwald–Giemsa for microscopic analysis. One hundred cells per participant were scored for nuclear abnormalities including micronuclei (MN), binucleated cells (BN), and nuclear buds (NB). Statistical analysis was carried out using SPSS v25, with p < 0.05 as the significance threshold. Results showed that the exposed drivers had markedly higher frequencies of nuclear anomalies compared to controls. The mean micronucleus frequency in the exposed group (8.00 ± 0.05 per 100 cells) was about 80 times higher than in the control group (0.10 ± 0.01), while BN and NB frequencies were increased 12-fold and 23-fold respectively. The total nuclear abnormality frequency was 165.00 ± 0.36 in exposed drivers versus 10.20 ± 0.94 in controls. Although the differences were not statistically significant, the biological trend suggests cumulative genotoxic stress from chronic exposure to vehicular pollutants. Routine biomonitoring and stricter air-quality measures are recommended to protect occupationally exposed populations.