Risk of contamination of raw materials and foodstaffs by mycotoxins, pesticides and biological contaminants. Detection methods in place. Contamination of selected raw materials by mycotoxins.

Presented study summarises the latest results of national and European projects, which were carried out at Department of Food Chemistry and Analysis, Institute of Chemical Technology, Prague. In following text there will be described themes: (i) comparison of mycotoxins levels that can be found in wheat and wheat-based products derived from organic and conventional farming, (ii) influence of mycotoxins of animal health, (iii) occurrence of mycotoxins in poppy seeds with the main attention to alternaria toxins, the main contaminants of this important agricultural commodity, (iv) influence of agricultural practices on levels of mycotoxins in spring barley. Optimisation of multiresidue methods for determination of pesticide residues has been done. The aim of the study was to compare performance characteristics of three modifications of the QuEChERS sample preparation method (original, citrate-buffering and acetate-buffering) for analysis of 324 pesticides and their metabolites. Original QuEChERS approach was proven to be the most rugged. Monitoring study was focused on apple samples; exceeding of maximum residue limit was not observed however multiple residues were found in more than half of samples. Positive analytes in samples of apple puree also did not exceed limits established by Directive 396/2005/ES. Nevertheless if intended for baby food production they should be assessed by uniform limit 0,01 mg/kg. Totally 33 % of apple puree did not fulfil this limit.CZ; cs; jana.hajslova@vscht.c