En cas de doute, par exemple dans le cas de céréales multigrains dont certains grains viennent peut-être d'une plante dérivée de la biotechnologie, mélangés à d'autres grains l'étiquette dirait simplement «peut» contenir, etc.
In a case where there was any doubt—for example, if they're dealing with a commodity where grains that may have come from a plant derived through biotechnology are mixed with those that are not, with commingling taking place—then the labelling would simply say “may” contain.