Measurement of benzene, toluene, xylene in small biological samples by syringe equilibrium / headspace gas chromatography

Background: Benzene, toluene, and xylene (BTX) are ubiquitous in the community environment. However, workers who handle them are concerned about adverse effects such as neurotoxicity and carcinogenicity. On the other hand, recently, in a general indoor environment, low-concentration BTX exposure due to release from a house has attracted attention as a cause of sick building syndrome and multiple chemical sensitivity. In order to understand the exposure status of BTX, it is effective to measure the unchanged BTX in biological samples such as blood and urine. However, the burden on the subject when collecting samples cannot be ignored.
Method: To generalize BTX measurement of biological samples in the field, the author has developed a syringe equilibrium / headspace gas chromatography using a small amount of biological sample and Portable GC and analytical accuracy was tested. Also, considering the case of bringing small samples back to the laboratory for analysis, ways to store biological samples containing BTX for extended periods of time was determined. And BTX contamination survey of newly built condominiums was conducted to verify the practicality.
Result: The reproducibility of syringe equilibrium / headspace gas chromatography with standard -added blood. In all BTX, the relative standard deviation was found to be within 10%, and according to the internal standard method, the relative standard deviation was found to be within 5%. BTX contamination survey of newly built condominiums completed successfully. Benzene and toluene were detected in the urine of the resident, but only toluene was detected indoors.
Conclusion: This method and the use of a portable GC with a photoionization detector enable assessment from microexposure in the living environment to occupational exposure levels with 50 μl microblood, reducing the burden on the subject. In addition, a long-term storage method of biological samples containing BTX, was developed to consider the case of bringing small samples back to the laboratory for analysis.