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Development of a Novel Mass Spectrometric ... - Jacobs University

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Results and Discussion<br />

my knowledge, no analyses or other kinds <strong>of</strong> monitoring activities have<br />

specifically utilized a precise analytical method to determine accurate data<br />

concerning the composition <strong>of</strong> the existing solid waste in uncontrolled dumps.<br />

Since these dumps are thought to be sources <strong>of</strong> hazardous complex mixtures and<br />

are hitherto unknown which components are present in these mixtures, I suggested<br />

to apply our current light shredder waste analytical methodology to such complex<br />

mixture <strong>of</strong> mixed solid waste in Lebanon. Samples were brought from ‘Garbage<br />

Mountain’ in the city <strong>of</strong> Saida. Two samples were taken from the garbage<br />

mountain at different intervals <strong>of</strong> time in May 2011 and July 2011. The samples<br />

were extracted, purified and measured in a similar fashion to the light shredder<br />

waste in Bremen. Sample 1 appears as in figure 3-60 to have a relatively higher<br />

mass distribution (m/z 200 to 800), but similar collection <strong>of</strong> signals compared to<br />

light shredder waste. The negative MS spectrum <strong>of</strong> the first sample was as well<br />

obtained.<br />

The mass spectrum observed in figure 3-61 demonstrated the presence <strong>of</strong> few<br />

polychlorinated biphenyls compounds. It included hexachlorobiphenyl at m/z<br />

340.9, heptachlorobiphenyl at m/z 374.8 and octachlorobiphenyl at m/z 408.8 that<br />

were identified by the (-) APCI method. This shows that even with the different<br />

nature and source <strong>of</strong> the solid waste in Lebanon, the method can be beneficial in<br />

identifying PCBs elsewhere. The low relative abundance <strong>of</strong> the PCBs is related to<br />

the fact that the sample belongs to a heterogeneous and untreated waste dump.<br />

This finding gives an indication that the remaining series <strong>of</strong> PCBs can be present.<br />

Knowing that there is a wide range <strong>of</strong> toxic substances (e.g. tannery waste and<br />

paints) that arrive at the waste site on a daily basis, this can be the source <strong>of</strong> toxic<br />

PCBs pollutants.<br />

Regarding the second sample, the positive mass spectrum shown in figure 3-62,<br />

appears to have also an equal number <strong>of</strong> compounds as compared to light shredder<br />

waste. However the negative mass spectrum <strong>of</strong> this sample doesn’t contain any<br />

PCBs as far as shown in figure 3-63. The work done with waste samples from<br />

Lebanon is considered a remarkable groundwork study towards a critical<br />

89

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