Evaluation of heavy metals and biomarkers of deoxyribonucleic acid damage in state employment and expenditure for result contract workers in Yenagoa

Igri B. Ofor, Enebrayi N. Onitsha, Solomon E. Aginaye


Background: Youth unemployment and poverty in Southern Nigeria is high, thus many youths are easily recruited as dock workers and casual labourers without considering the occupational hazards associated with such jobs. This study evaluated some heavy metals and DNA damage biomarkers in state employment and expenditure for result (SEEFOR) contract workers, in Yenagoa.

Method: One hundred subjects between the age range of 20 to 55 years, comprising fifty of SEEFOR contract workers and fifty unexposed individuals as control in the study. Blood samples were collected, separated and sera used for the analyses of heavy metals and DNA damaged biomarkers using enzyme linked immunosorbent assay and atomic absorption spectrophotometry.

Results: The result showed statistically non-significant difference (p>0.05) values of cadmium, chromium, vanadium, nickel, arsenic and DNA damage biomarkers at the baseline compared with the control group. Cadmium, vanadium and 8-NO2-Gua at the 6th month showed statistically significant difference (p<0.05). Statistically significant (p<0.05) increase at 12th month were equally observed in cadmium, vanadium, nickel, arsenic, and 8-NO2-Gua compared with the control. Heavy metals cadmium, chromium, Vanadium values showed statistically significant (p<0.005) increase in both the 18th and 24th month. DNA damage biomarkers 8-NO2-Gua, 4HNE, and BPDE levels also showed a significant (p<0.005) increase at the 18th and 24th month when compared with the control group.

Conclusions: The study suggest that the probability of occurrence of diseases related to heavy metal bioaccumulation and DNA damage originating from oxidative stress, might be higher among SEEFOR road construction workers with time.


Heavy metals, SEEFOR, DNA damage biomarkers

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