Document Type : Original Article
Authors
- Fereshteh Aliasghari 1
- Seyede Mahsa Taghavipour 2
- Nadia Mohammadi 2
- Fatemeh Rahimian 2
- Anahita Fakherpour 2
- Mohammad Fararouei 3
- Esmaeel Soleimani 4
1 Research Center for Health Sciences, Institute of Health, Shiraz University of Medical Sciences, Shiraz, Iran
2 Student Research Committee, Shiraz University of Medical Sciences, Shiraz, Iran
3 Department of Epidemiology, School of Health, Shiraz University of Medical Sciences, Shiraz, Iran
4 Department of Occupational Health and Safety Engineering, School of Health, Shiraz University of Medical Sciences, Shiraz, Iran
Abstract
Background: Previous studies on the relationship between benzene exposure and hematotoxicity have reported inconclusive findings, particularly at low exposure levels. This study aimed to investigate the potential relationship between low-level benzene exposure and changes in hematological parameters among petrochemical workers.
Methods: In this cross-sectional study, 495 benzene-exposed workers and 217 sex-matched non-exposed controls were assessed. Demographic, occupational, and medical data were collected. Air monitoring was conducted to determine benzene exposure, and the time-weighted average (TWA) was calculated. Blood samples were analyzed for hematological parameters. Data were analyzed using SPSS version 22.0. All exposures were within the OSHA permissible exposure limit (PEL). The mean TWA benzene exposure among the exposed group was 0.07±0.37 ppm.
Results: After adjustment for confounders, statistically significant associations were observed for red blood cell (RBC) count and mean corpuscular volume (MCV). No significant associations were found for other hematological parameters.
Conclusion: RBC count and i ts i ndices, particularly MCV, appear to be more sensitive to low-level benzene exposure than
other blood parameters. These findings suggest that benzene may exert hematotoxic effects even at concentrations below the current OSHA PEL-TWA.
Keywords
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