Study of deoxyribonucleic acid (DNA) damage in blood lymphocytes of pedicab drivers using the comet assay

• Main Authors: Sioson, Jacqueline L., Ulanday, Maria Leonora A.
• Format: text
• Language: English
• Published: Animo Repository 2009
• Subjects: DNA damage; Pollution—Physiological effect; Other Physics
• Online Access: https://animorepository.dlsu.edu.ph/etd_bachelors/5058
• Institution: De La Salle University

People who are working in an urban setting are more likely to be exposed to numerous environmental toxicants. How much damage these harmful agents can do one's body/health is quite difficult to determine. Recently, a new and sensitive technique called COMET assay has become popular and widely used for biomonitoring and occupational exposure studies. Pedicab drivers are unique workers along the selected streets of Metro Manila. They ply the side streets of the city by pedaling their way on their bicycles for short distances not normally serviced by regular buses jeeps and taxis. These drivers are out on the streets for long hours and are exposed to the polluted atmosphere of the streets typical of any urban setting or metropolis. Twelve pedicab drivers agreed to participate in this study aimed at determining whether exposure to environmental toxic materials will have an effect on the DNA, genetic material. From each driver, 4 ml of blood was extracted and these samples were processed for DNA extraction and consequently for COMET assay. Another 12 non pedicab drivers volunteered as control subjects. DNA damage was measured using three parameters: tail length, % DNA in tail and tail moment. Results showed that the mean values of tail length between the pedicab drivers and reference subjects are 29.05 and 9.04 respectively. For the tail moment the mean values are 6.25 for the drivers and 0.94 for the reference subjects. More so, for the % of DNA in tail, the mean values are 17.56 for the drivers and 6.34 for the reference subjects. These data were analyzed using the Wilcoxon Mann- Whitney test to determine whether the differences in these means are statistically significant. Results of analysis revealed that the DNA damage scored among drivers as seen in these 3 parameters (Tail moment, tail length and % of DNA in tail) were significantly higher than those observed among the reference group. From these data, we may infer that constant exposure of the pedicab drivers to environmental toxicants (e.g. air pollutants) could account for this increased DNA damage in their lymphocytes based on the 3 parameters described.