A direct reading method for chlorinated hydrocarbons in breath.

Area of Science:

• Occupational Health
• Analytical Chemistry
• Environmental Monitoring

Background:

• Tetrachloroethylene and 1,1,1-trichloroethane are common industrial solvents.
• Accurate breath monitoring is crucial for assessing occupational exposure.
• Existing methods may be time-consuming or require specialized equipment.

Purpose of the Study:

• To develop and validate a direct reading method for breath analysis of tetrachloroethylene and 1,1,1-trichloroethane.
• To assess the method's accuracy and reliability compared to gas chromatography.
• To provide a practical tool for monitoring solvent exposure.

Main Methods:

• A two-step procedure involving breath sampling in a bag.
• Analysis using colorimetric detector tubes for solvents and carbon dioxide.
• Comparison with a reference gas chromatographic method.

Main Results:

• The method accurately measures tetrachloroethylene and 1,1,1-trichloroethane from 2.5 to 30 ppm.
• Good agreement was observed with gas chromatography, with a systematic proportional error < +13% for tetrachloroethylene.
• Repeatability showed standard deviations from 6% to 39%.

Conclusions:

• The described direct reading method is a viable and accurate technique for breath analysis of these solvents.
• It offers a practical alternative for occupational exposure assessment.
• The inclusion of carbon dioxide measurement accounts for physiological variations.