The National Reference Center for Pesticide Residues of the Public Health Authority of the Slovak Republic has implemented methods for the determination of over 200 pesticides in baby food. Compared to adults, newborns have significantly higher food consumption per body weight, which leads to the need to control the presence of pesticides and their residues at very low concentration levels. This requires very low limits of determination and detection. This is associated with high demands on sample preparation, sensitivity of the method used and instrumentation. High-performance liquid and gas chromatography with tandem mass spectrometric detection (LC-MS/MS, GC-MS/MS) were used to analyze the final sample extracts. Before using the methods for the determination of pesticides, various validation parameters were checked for each pesticide residue according to the SANTE document from 2021.

In terms of selectivity and specificity, the blank response and the ratio of quantitation and qualification ions in the sample were not allowed to exceed 30%. In terms of linearity, deviations from the calibration line were allowed to be 20% and changes in response at calibration levels measured before and after the sample sequence had to be within 30%. In terms of accuracy, the accepted recovery is in the range of 60-140%, the residue reproducibility is within 20% and the measurement uncertainty is within 50%.

The determination of selected pesticides is accredited by the Slovak National Accreditation Service. The accuracy of the methods is verified at least once a year by participating in international comparative tests. Our laboratory achieves satisfactory results in the tests.

Baby food samples were pre-treated using the QuEChERS method. The results of official pesticide control and European monitoring in baby food carried out over the last 10 years indicate the safety of baby food, in terms of pesticide content, and none of the tested samples exceeded the permitted limit.