10 07 29 Master thesis Juliana Leon - e-Waste. This guide

potentially hazardous 17 CRT glass were dumped or landfilled. From this quantity,
around 66% take its origin in households, 17% in MLBs, and 17% in official
institutions; thus, all consumer categories are contributing to this practice. This is due
to the inexistence of an interface diverting CRT glass flows from the informal to the
formal sector; thus, once a CRT enters the IS it is never going to be safely disposed,
because nobody would assume this cost.
Figure 20: Material flow of computer CRT glass within the formal and informal sector in
Colombia. Base scenario calculated for the year 2009.
As shown in Figure 21, the improper disposal of CRTs could be much higher (1,910
tons for the “worst case” scenario) because the quantity for the “state of the art”
disposal is pretty well known and, thus, almost constant between the scenarios.
Again, refurbishment is very high and without it, the improperly disposed CRT glass
would probably be much higher. The field survey shows that even if new monitors
17 The content of lead and other heavy metals on CRT glass depend on the location of the glass in the
CRT. Panel glass contains 1.9 to 14.2% of barium oxide (BaO) and can also contain up to 11.6% of
strontium oxide (SrO) and up to 3.3% of lead oxide (PbO), while funnel glass PbO content range from
11.6 to 24.6% (BMLFUW, 2006). According to Musson et al., (2000), leachate lead concentration from
funnel glass exceed by far EPA regulatory limits what is not the case for panel glass.
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