Results of metal concentrations in PCB samples are analytically shown in Table 2. In general, concentration values for Al varied from 0.64 wt.% (in Samsung 2002–2006 sample) to 1.58 wt.% (in Nokia 2007–2011 sample). As far as Cr is concerned, concentrations were similar to Al, with the lowest value (0.054 wt.%) found in Samsung 2002–2006 sample and the highest (0.85 wt.%) in 2002–2006 sample.