Validated method for measuring airborne concentrations of tert-butylphenols for occupational exposure assessment

Objectives This study aimed to develop a method for measuring airborne concentrations of tert-butylphenols (tert-BPs) to assess workers' occupational exposure. Methods Air samples were collected using an XAD-7 sorbent tube. Tert-BPs were desorbed from the sorbent with methanol, and their concentrations in the desorbed solutions were determined via high-performance liquid chromatography with fluorescence detection. Method validation included evaluation of retention efficiency, storage stability, method quantitation limit, and reproducibility. Results The retention efficiencies for 2-tert-BP, 3-tert-BP, and 4-tert-BP in the XAD-7 sorbent tube were 89%–97%, 93%–96%, and 95%–96%, respectively. Relative standard deviations, reflecting the overall reproducibility of the proposed method, ranged from 0.5% to 5.9% for all tert-BPs. Tert-BPs remained stable on the XAD-7 sorbent tube for at least 7 days at 4°C. The method quantitation limit was 0.118 μg/sample for each tert-BP. Conclusions The developed method provides a robust and reproducible approach for assessing occupational exposure to airborne tert-BPs, enabling accurate determination within a concentration range of 0.8–160 ppb. This method can facilitate more precise risk assessments in occupational environments.