Reference values for blood toluene in the occupationally nonexposed general population

Area of Science:

• Environmental Health
• Occupational Health
• Analytical Chemistry

Background:

• Toluene is a common industrial solvent with potential health implications.
• Understanding baseline blood toluene levels in different occupational groups is crucial for exposure assessment.

Purpose of the Study:

• To determine blood toluene levels in occupationally nonexposed rural and urban workers.
• To compare these levels with those in chemical workers.
• To investigate the influence of smoking on blood toluene concentrations.

Main Methods:

• Gas chromatography-mass spectrometry (GC-MS) was used for blood toluene analysis.
• Blood samples were collected from 232 nonexposed subjects (rural and urban workers) and 37 chemical workers.
• Statistical analysis was performed to compare toluene levels across groups and factors.

Main Results:

• Mean blood toluene was significantly lower in rural (698 ng/l) and urban workers (984 ng/l) than in chemical workers (2789 ng/l).
• No significant difference in blood toluene was observed between rural and urban workers.
• Smokers exhibited higher blood toluene levels (median 606 ng/l) than nonsmokers (median 424 ng/l).
• Recent smoking (within 2 hours) markedly increased blood toluene levels (median 1170 ng/l).

Conclusions:

• Chemical workers have substantially higher blood toluene levels than general rural and urban workers.
• Smoking is a significant confounding factor for blood toluene measurements.
• These findings provide valuable reference data for occupational and environmental exposure studies.