Food businesses are obliged to provide safe foods according to Article 14 of the General Food Law.
A food is presumed unsafe if it does not comply with the EU (or national) legislation governing its safety. As an example, this could be a food that contains an allergenic ingredient, which should be labelled in accordance with Directive 2000/13/EC, but is not.
Even if the food complies with the EU (or national) legislation governing its safety, a food business or a competent authority may have reasons to consider the food unsafe. This could occur if a food contains a very high concentration of cross-contact allergen, which could trigger a reaction in a significant number of allergic consumers.
The General Food Law: