The Relationship between Blood Lead Level and Neuro-psychological and Hematological Findings in Lead-Exposed Workers of Battery Industry

Background: Hematological effects and digestive and neuro-psychological signs and symptoms are some manifestations of lead toxicity. However, there are conflicting reports of their prevalence among lead exposed workers and their relationship with blood lead levels (BLL). This case- control study assessed the relationship between BLL and hematological indexes and digestive (abdominal colic, iron taste), neural (tinnitus, anosmia, paresthesia, weakness, dizziness, headache), and psychological (fatigue, sleep disturbance, forgetfulness) findings in battery-manufacturing workers. Methods: Cases and controls were a sub-sample of lead exposed and non-exposed workers in battery-manufacturing industry. BLL concentrations, hematological indexes, and clinical manifestations were evaluated in the two groups. Statistical analyses were performed using SPSS software. Results: There were no significant differences in age and years of work between the two groups. BLL (mean ±SD) was significantly higher in the lead exposed group than in the controls (36.54 ± 4.34µg⁄dl and 8.82 ± 3.96 µg⁄dl, respectively) (P<0.001). There was a significant relationship between BLL and headache, fatigue, paresthesia, weakness, forgetfulness, sleep disturbance, iron taste, anemia, and eosinophil level. However, there was not a significant relationship between anosmia and BLL. Conclusion: BLLs correlated with some clinical and para-clinical findings. Therefore, preventive measures towards exposure to lead at work places, and routine hematological investigations should be included in bio-monitoring the health status of lead workers.