The content of heavy metals in food packaging paper boards: an atomic absorption spectroscopy investigation

The levels of four representative heavy metals-Cd, Cr, Pb and Hg-were measured by atomic absorption spectroscopy (AAS) in 15 different samples of paper boards, used as packaging materials for various pasta and cereals products. The levels of heavy metals have been measured in all the samples according to the two procedures presently proposed by the European Council: (i) after immersion in distilled water for 24h at T = 23 degrees C (extraction test); and (ii) after immersion in 3% v/v acetic acid for 24 h at T = 40 degrees C (migration test). The results of the present investigation show that most of the samples of food packaging paper board contain concentrations of heavy metals that are higher than the limits fixed by the European Council. Moreover, the results also show that there is a remarkable difference among the levels of heavy metals depending on the procedure of sample pretreatment. Our observation points out that the pretreatment usually indicated as 'migration test', being remarkably more drastic than the 'extraction test', should be imposed in all those cases in which a higher degree of safety is requested. (C) 1998 Canadian Institute of Food Science and Technology. Published by Elsevier Science Ltd.