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A database has been compiled with the levels of important contaminants (mycotoxins, heavy metals and pesticides) measured from 2002 to 2005 in winter wheat (Triticum aestivum) grown in Belgium according to the organic and conventional farming systems. Assuming no further change in contaminant levels during cereal processing and during the preparation of foodstuffs, conservative intakes are estimated for the consumers of cereal-based products such as flour, bread, breakfast cereals, dough and pastry. The results show that for the consumer of organic foodstuffs, estimated daily intakes are 0.56 µg deoxynivalenol (DON), 0.03 µg zearalenone (ZEA), 0.19 µg Cd, 0.28 µg Pb and 0.0006 µg Hg kg−1body weight, taking into account the average contaminant levels in unprocessed grains and the average cereal products consumptions in Belgium. For the consumers of conventional foodstuffs, the corresponding estimated daily intakes are 0.99 µg DON, 0.06 µg ZEA, 0.17 µg Cd, 0.12 µg Pb and 0.0007 µg Hg kg−1body weight. In addition, it appears that for the consumers of conventional products, intakes of some post-harvest insecticides have to be taken into account (0.11 µg chlorpyriphos-methyl, 0.2 µg dichlorvos and 0.24 µg pirimiphos-methyl kg−1bw). When expressed as a percentage of the tolerable/acceptable daily intake (TDI/ADI), it seems that the corresponding estimated (conservative) intakes are the highest for DON (56% for organic and 99% for conventional cereal products), ZEA (16% for organic and 32% for conventional cereal products), and Cd (19% for organic and 17% for conventional cereal products), all other estimated intakes of contaminants (including pesticides) being lower than 10% of the TDI/ADI.

The solid‐liquid distribution of radiocesium (137Cs) varies extensively among soil types. A statistical approach was used to relate 137Cs sorption with soil properties. Eighty‐eight pasture soils were sampled in Belgium. All soil samples were characterized for texture, cation exchange capacity, exchangeable K, Ca, and Mg content, pH and organic C content. Soil samples were equilibrated in a 10−1MCaCl2— 5.10−4MKCl solution. Adsorption of 137Cs was measured after 16 h in this medium. The solid‐liquid concentration ratio, KD, of 137Cs in this specific ionic scenario allows for the calculation of the Radiocesium Interception Potential (RIP), which in turn can be used for KDpredictions for a wide range of different ionic scenarios. The RIP varied from 54 to 11 200 mmolckg−1. Stepwise multiple regression between RIP and soil characteristics yielded statistically significant models (P< 0.001) for samples from each northern and southern Belgium. For northern Belgium the regression model only included texture fractions (R= 0.86, n= 62) whereas for southern Belgium the regressors were texture fractions and soil pH (R= 0.88, n= 26). The correlations between the RIP and soil characteristics depend strongly on the geological origin of the soil.