Abstract
Objectives: This study aimed to establish a method to determine workers’ exposure concentrations to airborne nitrilotriacetic acid (NTA).
Methods: The sampler used an air sampling cassette containing a glass-fiber filter (GFF). After sampling, NTA extracted from the GFF using ultrapure water was derivatized using a boron trifluoride-methanol complex methanol solution and analyzed using a gas chromatograph-mass spectrometer. The developed method was validated for the following parameters: retention efficiency, storage stability, method quantitation limit, and reproducibility.
Results: The retention efficiency for NTA on the GFF was 94%-101%, with the relative SD indicating the overall reproducibility (range 0.9%-2.4%). NTA on the GFF was stable at 4°C for at least 7 days. The method quantitation limit was 4.8 μg per sample.
Conclusions: The developed method will be useful for risk assessments because it can determine workers’ exposure concentrations to NTA ranging from 0.02 to 4 mg/m3 in a 240 L sampling volume; the quantitation limit is 4.8 μg per sample.
