A simple method for the analysis of neonicotinoids and their metabolites in human urine

An analytical method for measuring seven neonicotinoid insecticides and four of their metabolites in human urine was developed based on solid phase extraction and ultra-performance liquid chromatography-tandem mass spectrometry. The accuracy and precision of the method at three fortification levels (0.25, 2.50 and 10.0ngmL(-1)) of the target analytes in 500 mu L of urine were 83.7-119% and 2.0-11.3%, respectively. The average inter-batch precision (fortification level: 2.50ngmL(-1)) was 5.5-11.9%, and the limits of quantification ranged from 0.01 to 0.05ngmL(-1) depending on the neonicotinoid. The method was applied to 20 spot urine samples collected from healthy adults in Albany, New York, United States. At least two of the neonicotinoids or their metabolites were found in each urine sample (median concentration: nd-0.43ngmL(-1)). The method is simple, sensitive and precise, and is well suited for measuring neonicotinoids in human urine for future exposure assessment studies.