Zearalenone is a mycotoxin produced by several Fusarium species. It is commonly found in maize but can be found also in other crops such as wheat, barley, sorghum and rye. The European Commission asked the European Food Safety Authority to review the safety of zearalenone and the risk to consumers of a possible increase of the maximum level (ML) for zearalenone in breakfast cereals. A total of 13,075 analytical results obtained on food samples and 9,877 results on unprocessed grains sampled by 19 European countries in 2005 2010 were used in the evaluation. The highest concentrations of zearalenone were reported for wheat bran, corn and products thereof (e.g. corn flour, cornflakes). Grains and grain-based foods, in particular grains and grain milling products, bread and fine bakery wares, made the largest contribution to the estimated zearalenone exposures. Vegetable oils also made an important contribution to the zearalenone exposure. The critical effects of zearalenone result from its oestrogenic activity. Based on recent data in the most sensitive animal species, the pig, and taking into account comparisons between pigs and humans, the Panel on Contaminants in the Food Chain established a tolerable daily intake (TDI) for zearalenone of 0.25 μg/kg b.w. Estimates of chronic dietary exposure to zearalenone based on the available occurrence data are below or in the region of the TDI for all age groups and not a health concern. A potential increase in the ML for zearalenone in breakfast cereals from 50 µg/kg to 75, 100, 125 or 150 µg/kg is unlikely to result in a chronic dietary exposure exceeding the TDI. In a worst case scenario it is possible that an individual could consume the same batch of breakfast cereal containing zearalenone at the ML every day for 2 to 4 weeks, in which case exposures may exceed the TDI.