Objective To evaluate the relationships between time-weighted average (TWA) of glyphosate and urinary concentrations of glyphosate and its metabolite aminmethyl phosphonic acid (AMPA) in selected occupational groups.
Methods A total of 134 exposure workers and 152 control workers from five glyphosat manufacturers were selected as study subjects. Glyphosate in workplace air was sampled by using personal sampler to calculate TWA. The concentrations of glyphosate and its metabolite AMPA in urine of the subjects were detected by gas chromatography-mass spectrometry. Urinary concentrations of glyphosate and AMPA were compared by nonparametric test. The relationships between TWA of glyphosate and urinary concentrations of glyphosate and AMPA were evaluated by correlation analysis.
Results The estimated TWA values of glyphosate of various posts in the exposure group were from < 0.02 mg/m3 to 34.58 mg/m3. The positive rates of glyphosate and AMPA in urine of the exposure workers were 86.6% and 81.3% respectively; the urinary concentrations were < 0.020-17.202 mg/L and < 0.010-2.730 mg/L respectively; the medians were 0.292 mg/L and 0.068 mg/L respectively. The concentrations of glyphosate and AMPA in the exposure group were higher than those in the control group (P < 0.05). Urinary concentrations of glyphosate and AMPA were positively associated with TWA of glyphosate of the exposure workers (r=0.755, 0.682, P < 0.01) respectively; also, there was a positive association between the urinary concentrations of glyphosate and AMPA (r=0.472, P < 0.01).
Conclusion The concentrations of glyphosate and AMPA in urine of workers have correlations with the TWA of glyphosate in workplace air.
DownLoad: