Prevalence of allergen cross-contamination in prepacked foods with PAL. (* Note: Zurzolo et al. also assessed products for milk, egg, hazelnut and soya; these allergens were not detected in any product . The higher rates of allergen detection in surveys by Crotty et al.  and Pele et al.  are most likely due to the food products included: dark chocolate and cookie biscuits/chocolate respectively).