Automotive shredder residue: a survey of the hazardous organic micro-pollutants spectrum in landfill biogas

In this study, we report an extensive set of analytical results on the quality of the biogas produced by a landfill of automotive shredder residues. In particular, the investigation was directed towards the identification of a spectrum of Polycyclic Aromatic Hydrocarbons (PAHs; 16 compounds) and a wide range of Volatile Organic Compounds (VOCs; 35 compounds). This article highlights the most important indications of toxicological concern for the detected compounds. Among the PAHs, chrysene shows the highest concentration, followed by pyrene and benzo(b)fluoranthene. Dibenz(a,h)anthracene, the most carcinogenic of the tested compounds, displayed results below the limit of analytical detectability. Benzo(a)pyrene, another typical carcinogenic compound, was detected at low concentrations. With regard to VOCs, the survey revealed a relevant concentration of toluene (found in fuels and paint thinner) significantly higher than the other compounds. Noticeable amounts of hexane, trichloromethane and acetone were also found.