Conclusions
The method developed in this study allows 4-h personal exposure monitoring of glyphosate at 0.250-500 μg/m3 . Thus, this method can be used to estimate worker exposure to glyphosate.
Methods
The proposed method was assessed as follows: recovery, stability of samples on storage, method limit of quantification, and reproducibility. Glyphosate in air was sampled using an air-sampling cassette containing a glass fiber filter. Ultrapure water was used to extract glyphosate from sampler filters. After derivation with 9-fluorenylmethyloxycarbonyl chloride, samples were analyzed by high-performance liquid chromatography using a fluorescence detector.
Results
Spiked samples indicated an overall recovery of 101%. After 7 days of storage at 4°C, recoveries were approximately 100%. The method limit of quantification was 0.060 μg/sample. Relative standard deviations representing overall reproducibility, defined as precision, were 1.4%-1.8%. Conclusions: The method developed in this study allows 4-h personal exposure monitoring of glyphosate at 0.250-500 μg/m3 . Thus, this method can be used to estimate worker exposure to glyphosate.