Proceedings

Disposal and handling of sewage sludge are increasing problems in Europe due to the increasing quantities of sewage sludge produced. The sewage sludge contains small fractions of toxic chemicals, which results in problems with safe use of the sewage sludge on agricultural land. From an ecological and economical point of view, it would be essential to establish methodologies, which could allow sludge to be reused as fertilizers on agricultural land. A literature survey was carried out in order to compile data concerning the content of chemical pollutants in sewage sludge. The data were evaluated using the chemical hazard identification and assessment tool (CHIAT) methodology. The methodology identifies the problematic and hazardous compounds and passed on to a hazard assessment step, which involves an identification of receptors, exposure pathways, and effects assessments, leading to estimations of risk quotients (e.g. predicted environmental concentrations (PEC)/ predicted no-effect concentrations (PNEC) ratios). Approximately 200 compounds were evaluated and a list of compounds that constitute a hazard or a problem namely the potential priority pollutants. The list included 15% of the evaluated compounds, which amongst others were a hormone, chlorophenols, pharmaceutical compounds, and PAHs.

KEYWORDS Hazard assessment, Sewage sludge, Xenobiotic organic compounds