Determination of mercury in glass: A new analytical need in the evaluation of the packaging waste quality

Abstract

In December 1989 the "Coalition of Northeastern Governors" of the United States of America developed a new toxics legislation with the aim to prohibit the intentional addition of lead, cadmium, chromium(VI), and mercury to packaging and packaging materials, fixing as a sum of these elements a scale of tolerable limit values, up to a final target of 100 ppm to be finally reached in 1994. Testing methods have not been indicated, but it is a fact that analytical procedures for the determination of mercury in glass are not often reported in literature. In this paper a closed-system decomposition procedure is proposed and mercury analyzed by cold vapour atomic absorption spectrometry. Employing this procedure has given excellent results allowing the total recovery of mercury contained in the glass decomposition solutions. Tests of the analytical accuracy have also been performed on a soda-lime-silica glass to which traces of mercury have been incorporated by experimental melting. As final point the possible presence of mercury traces in glass packaging containers of different production, type and colour was investigated, but all tests were negative.