Abstract: This study aimed to investigate the ranges of 3-monochloro-1,2-propanediol (3-MCPD) and its fatty acid esters concentrations in the Chinese diet in order to offer supporting data to establish a maximum tolerable daily intake for 3-MCPD in China. The research objects in this study were 39 Chinese dishes. In this method, sulfuric acid methanol was used as ester cleavage reaction of chloropropanol esters, and then the extracts were derivatized with heptafluorobutyrylim idazole (HFBI) and analyzed with gas chromatography-tandem mass spectrometry (GC-MS/MS). Good linearity was obtained with correlation coefficients from 0.997 2 to 0.999 5. The spiked recoveries were in the range of 95.0%–115.0%, with relative standard deviations (RSDs) ranging from 2.9% to 6%. The results showed that both 3-MCPD and its esters were found in all dishes analyzed. The average concentrations of 3-MCPD esters and 3-MCPD were 516.11 and 17.88 μg/kg in restaurant dishes, and 75.86 and 10.43 μg/kg in school canteen dishes, respectively. Difference cooking methods had different influences on the generation of 3-MCPD and its esters, in decreasing order of importance: deep frying > griddling > stir frying > braising > stewing. The concentration of 3-MCPD in both canteen and restaurant dishes did not exceed the provisional maximum tolerable daily intake (PMTDI) established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), and the concentration of 3-MCPD esters in canteen dishes did not exceed the PMTDI either, while that in restaurant dishes was 2.2 fold higher than the PMTDI.

Key words: 3-monochloro-1,2-propanediol, 3-monochloro-1,2-propanediol fatty acid esters, dishes, gas chromatography tandem mass spectrometry, exposure