European directives for official controls of some contaminants in cereals such as mycotoxins set methods for sampling and analysis. The sampling protocols are strict and not very practical. The composition of batches of cereals is rarely homogeneous and, in particular, certain contaminants like Fusarium-mycotoxins are distributed in a non-uniform way. Sampling is therefore a procedure which requires a great deal of care; it is necessary to get a guaranteed representative sample before initiating analysis. For four years, studies have been undertaken by a French working group of associated storage organizations and suppliers of sampling devices in order to:

• evaluate mycotoxin distributions in cereal batches,
• compare different sampling protocols, including the European directive (reference method),
• determine the relationship between the number of increments and the total analysis uncertainty, and
• define an acceptable sample weight for laboratory analysis.