A method for determining workers' exposure concentration to airborne nitrilotriacetic acid

Area of Science:

• Occupational Health
• Analytical Chemistry
• Environmental Monitoring

Background:

• Nitrilotriacetic acid (NTA) is a chelating agent with potential occupational health implications.
• Accurate measurement of airborne NTA is essential for assessing worker exposure levels.
• Existing methods may lack the sensitivity or practicality for routine workplace monitoring.

Purpose of the Study:

• To develop and validate a reliable method for quantifying airborne nitrilotriacetic acid (NTA) in occupational settings.
• To establish a sensitive and reproducible analytical procedure for NTA determination.
• To provide a tool for accurate risk assessment of NTA exposure in the workplace.

Main Methods:

• Air sampling using a glass-fiber filter (GFF) cassette.
• Extraction of NTA from the GFF with ultrapure water.
• Derivatization using a boron trifluoride-methanol complex.
• Analysis via gas chromatography-mass spectrometry (GC-MS).

Main Results:

• High NTA retention efficiency on the GFF (94%-101%).
• Excellent reproducibility with relative standard deviation (RSD) ranging from 0.9% to 2.4%.
• NTA stability on the GFF at 4°C for at least 7 days.
• Method quantitation limit of 4.8 μg per sample.

Conclusions:

• The developed GC-MS method provides accurate quantification of airborne NTA.
• The method is suitable for determining worker exposure concentrations from 0.02 to 4 mg/m³.
• This validated technique is valuable for occupational risk assessments related to NTA exposure.