Blood biomarkers in metal scrap workers accidentally exposed to ionizing radiation: a case study

The detrimental effect of nuclear accidents due to localized or whole body radiation exposure results in severe cellular damage. The current study was carried out to evaluate radiation-mediated variability in blood components of metal scrap workers exposed accidently to cobalt-60 source. Blood samples collected initially from five hospitalized patients, coded P1-P5, were processed for total leukocyte counts (TLC), platelet (PLT) counts, haemoglobin, estimation of DNA double strand breaks by measuring phosphorylated form of H2AX (γ-H2AX) and chromosomal aberrations (dicentrics). Blood cells count (TLC), in all the patients except P2, was found decreased. Dicentrics increased in all the five patients. γ-H2AX was found significantly elevated in patients P2 and P4. After 3 days, 21 subjects working in close vicinity of accident site were evaluated for the above-mentioned markers to confirm their possibility of radiation exposure; however, all the parameters in these subjects were found within normal limits. Blood from patients P1-P5 was collected again after 11 days. Studies revealed exorbitant increase in γ-H2AX in lymphocytes and monocytes of patients P1, P4 and P5. TLC and PLT count in these patients had fallen further. Dicentrics declined with time in all the five patients. Based on the studied blood biomarkers, we conclude that the five subjects showed signs of radiation exposure. Measurement on radiation dose could not be performed in the current study; however, the generated data particularly on dicentrics provide ample evidence of radiation exposure.