Validation Study for Establishing a Standard Test Method for Volatile Organic Compounds in Indoor Air in Japan using Thermal Desorption

The Committee on Sick House Syndrome: Indoor Air Pollution, established by the Ministry of Health, Labour and Welfare of Japan, is reviewing indoor air quality guidelines. A comprehensive exposure assessment is essential for pollutants with revised guideline values or newly developed candidate pollutants, necessitating the development of standardized test methods for an accurate evaluation. However, the available test methods that have been provided as a standard test method (measurement manual) were introduced over 20 years ago. Its applicability to pollutants for which guideline values have been established since then had not been examined. Therefore, we established a test method for six compounds based on the current guideline values and three candidate compounds that underwent initial risk assessment. This method considered the new guideline values established after 2001 using solid-phase adsorption-thermal desorption-gas chromatography/mass spectrometry, as indicated in the measurement manual for volatile organic compounds. This method was validated at four institutions using samples at approximately 1/10th the concentration of the current, revised, and newly proposed guideline values, as of 2017. Results revealed that the average recovery of the four laboratories ranged from 84.2 to 95.6%, the repeatability ranged from 0.43 to 16%, which was <20% for all nine compounds, and the reproducibility ranged from 4.4 to 16%, which was <20%, thereby effectively achieving the target evaluation criteria. Therefore, this method could be presented as a standard test method for nine volatile organic compounds.