Comparison among five mutagenicity assays in workers producing polyurethane foams.

Area of Science:

• Occupational toxicology
• Environmental health
• Genetic toxicology

Background:

• Isocyanates and amines are used in plastic foam production.
• Occupational exposure to these chemicals may pose health risks.
• Cytogenetic and urinary mutagenic assays are used to assess genotoxicity.

Purpose of the Study:

• To evaluate the genotoxic effects of occupational exposure to isocyanates and amines.
• To compare cytogenetic and urinary mutagenic parameters between exposed workers and referents.
• To investigate the influence of age and smoking on these parameters.

Main Methods:

• Cytogenetic analysis: chromosomal aberrations, sister chromatid exchanges (SCE), and micronuclei in lymphocytes.
• Urinary mutagenic assays: thioether concentrations and mutagenic activity (Salmonella TA98, E. coli WP2 uvrA).
• Air monitoring for toluene diisocyanate and N-methylmorpholine.

Main Results:

• Increased mean values for most parameters in the exposed group, but only urinary thioether concentrations differed significantly.
• No conclusive evidence of genetic effects from occupational exposure via cytogenetic parameters.
• Significant effects of age on micronuclei frequencies and smoking on SCE, thioether concentrations, and Salmonella mutagenicity.

Conclusions:

• Low occupational exposure levels may explain the lack of significant genotoxic findings.
• Smoking is a confounding factor influencing cytogenetic and mutagenic outcomes.
• Correlations between assays suggest a potential common metabolic pathway.