In 1994 new legislation (Directive 94/62/EC [12]), limiting the level of the most toxic heavy metals (Cr(VI), Cd, Hg and Pb) in packaging materials to 100 mg kg-1 (as a total amount) was introduced in the European Union. The Directive has become the basis for corresponding legislation acts in the EU member and candidate countries, including Poland [13-16]. These events have focused the attention of the scientists to the necessity of development of methods suitable for the examination of enormous amounts and a variety of packaging materials for trace amounts of elements (ng g-1, ?g g-1) that can occur in such materials. Papers, paperboards and plastics make the basis of packaging materials used. Traces of toxic substances in such materials can origin from contaminants occurring in various substrates (e.g. wood pulp, polymers), from numerous additives (e.g. catalysts, thermal stabilizers, adhesives, lubricants, antioxidants, pigments, printing inks) used in the production process as well as from process water and process equipment. A discussion of packaging materials produced as well as sources of toxic elements is presented in the paper in detail. Analytical methods for the determination of traces of various elements (chromium, cadmium, lead, mercury, arsenic, antimony, molybdenum, barium, copper and zinc) in packaging materials developed by the authors have been described. Digestion procedures used for the transformation of the analytes from materials of various matrices (polymer (polyethylene, polypropylene, polystyrene, poly(ethylene terephthalate)), paper and paperboard) into solution are presented in Table 1. The application of modern analytical technique, inductively coupled plasma-time of flight-mass spectrometry (ICP-TOFMS), to the detection of the elements has been described. The ICP-TOFMS technique offers detection limits (DLs) suitable for the determination of a range of elements that can occur in packaging materials. The technique offers multi-element capability, selectivity, possibility of simultaneous isotope determinations, extremely high data-acquisition speed (quasi-simultaneous measurement of all masses extracted from the plasma ion source), high ion transmission and high sample throughput [34, 35]. Data for the isotopes used for the detection of the analytes as well as the detection and quantification limits achieved by the authors are given in Table 2. Results for the level of the elements determined in four groups of packaging materials examined, I and II: of polymer matrices intended for food- and non-food-packagings, respectively, and III and IV: of paper and paperboard matrices (for food- and non-food-packagings, respectively) have been given in Table 3. Mass spectra of some materials chosen from particular examined groups are presented in Fig. 2.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.