The introduction of genetically modified herbicide tolerant rapeseed has raised questions concerning the possible transfer of transgenes into wild relatives or neighbouring fields with similar crops. Pollen of rapeseed can be spread in the area and if a non-GM crop is fertilised by GM pollen, some percentage of the collected seed product will contain GM. Current regulation in the EU limits the allowed content. For conventional crops the critical level of GM contamination is in practice below 0.9%, which is the threshold value for labelling of GM in food and feed by the EU, although the limit for seeds is 0.1% in Serbia. In organic farming, the regulations do not allow the use of genetic engineering in the grain production system.