Interphase cytogenetics of workers exposed to benzene

Area of Science:

• Cytogenetics
• Toxicology
• Molecular Biology

Background:

• Benzene metabolites are known to induce numerical chromosome aberrations (aneuploidy) in human cells.
• Fluorescence in situ hybridization (FISH) is a key technique for detecting aneuploidy in interphase cells.

Purpose of the Study:

• To investigate the association between occupational benzene exposure and aneuploidy in human blood cells.
• To evaluate the utility of interphase FISH for monitoring benzene-exposed populations.

Main Methods:

• Interphase fluorescence in situ hybridization (FISH) was used for cytogenetic analysis.
• Blood samples from 43 benzene-exposed workers and 44 controls in Shanghai were analyzed.
• Chromosome 9 aneuploidy and its correlation with benzene exposure levels and hematotoxicity markers were assessed.

Main Results:

• High benzene exposure (> 31 ppm) significantly increased the frequency of chromosome 9 hyperdiploidy (trisomy 9), unlike lower exposure levels.
• A positive correlation was observed between chromosome 9 hyperdiploidy and urinary phenol levels, indicating internal benzene dose.
• Hyperdiploidy in exposed workers correlated with a decreased absolute lymphocyte count, a marker of benzene hematotoxicity.

Conclusions:

• High occupational benzene exposure induces aneuploidy, predominantly trisomy 9, in non-diseased individuals.
• Interphase FISH is a sensitive method for detecting aneuploidy in human populations exposed to environmental toxins.
• The findings underscore the potential genotoxic effects of benzene and the utility of cytogenetic monitoring.