Analysis and uncertainty estimation of zearalenone in cereal-based products by LC-MS/MS

A survey of zearalenone contamination was conducted on cereal-based products by using an immunoaffinity column with LC-MS/MS. The calibration curve showed good lineality, with correlation coefficients (R2) of 0.999 in the concentration range from 1 to 250 ng/mL. The limits of detection and quantification were approximately 0.3 μg/kg and 1.0 μg/kg, respectively. The recoveries in the barley tea, Misutgaru and snack ranged from 73.6-107.8%. Zearalenone was detected in 10 samples (11.2% incidence). The highest zearalenone contamination level was 29.7 μg/kg in the Misutgaru. This survey was conducted with uncertainty of measurement. The expanded uncertainty for zearalenone was estimated to be 44.9±5.0 μg/kg (k=2, 95% confidence level) and 128.7±7.9 μg/kg (k=2, 95% confidence level) for barley tea, 30.7±5.8 μg/kg (k=2, 95% confidence level) and 173.7±14.9 μg/kg (k=2.26, 95% confidence level) for Misutgaru, and 37.2±7.4 μg/ kg (k=2.31, 95% confidence level) and 151.0±10.4 μg/kg (k=2, 95% confidence level) snack at the level of 41.7 μg/kg and 166.7 μg/kg, respectively.