A substantial amount of chemical substances considered harmful to both man and the environment are part of the raw material from which packaging is made. The process of the migration of food packaging components to food depends on temperature, contact time, the contact surface between packaging and the food product and the product chemical composition. Plastics are widely used for the manufacture of packaging, due to their favourable properties and low production costs. Trace amounts of monomers from which a given polymer is produced together with auxiliary and refining substances added to plastics can permeate food products. The migration of low-molecular substances is also caused by the processes of depolymerisation, degradation and material destruction under the influence of such factors as: temperature, mechanical stresses and the influence of other chemicals. Heavy metals or their compounds are the most frequent inorganic compounds in packaging materials that pose a potential danger both to people and environment. Heavy metals in packaging materials can originate from raw materials used for production, or they can be introduced during processing. Also, auxiliary and refining substances or recycled materials used in the production of packaging materials such as recycled paper or aluminium, cullet or plastic re-granulates can be the source of heavy metals. Studies on the migration of harmful substance from packaging to food products are significant both from the point of view of health protection and the protection of the natural environment.