A labeling apparatus and method for continuously applying a layer of a radiation curable adhesives to plastic, sheet fed, cut and stack, labels, irradiating the adhesive on the labels, prior to and/or subsequent to adhering the labels to containers, e.g., a bottle, to render the adhesive sufficiently tacky to effectively permanently seal the labels to containers in a commercial labeling machine. The plastic labels can be clear, opaque (including metallized) plastic films and can be retained in a dispensing magazine prior to the application of the radiation curable adhesive to the labels.