Determination of five coumarins in toys by high performance liquid chromatography-tandem mass spectrometry

A rapid analytical method for the determination of five coumarins coumarin 7-methoxycoumarin dihydrocoumarin 7-methyl coumarin and 7-ethoxy-4-methyl coumarin in toys by high performance liquid chromatography-tandem mass spectrometry HPLC-MS/MS has been developed. After ultrasonic extraction in tetrahydrofuran the samples were analyzed by HPLC-MS/MS in multi-reaction monitoring MRM mode. Acetonitrile and 0. 1% acetic acid were used as the mobile phases with gradient elution. The linear ranges of calibration curves were 10 -1 000 mu g/L and the limits of quantification LOQ S/N > 10 were 2.0 mu g/L for all the analytes except that the LOQ for dihydrocoumarin was 5. 0 mu g/L. The recoveries of the five coumarins spiked in three types of samples were in the ranges of 93.2% - 105. 8% 97.3% - 103. 2% and 96. 8% - 102. 9% with the relative standard deviations in the ranges of 4. 35% - 8. 27% 3.65% - 6. 73% and 4.03% - 6. 45% respectively. The method was applied in the determination of 12 toy samples. The five analytes were found in 9 samples and in some cases the presence of quite high concentrations of these coumarins in the toys should be a matter of concern.