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Analysis of PCDD/Fs and dioxin-like PCBs in sewage sludges and general bio-wastes available for agricultural land application – Comparison between GC-IDHRMS and CALUX results.
Boekbijdrage - Boekhoofdstuk Conferentiebijdrage
Polychlorinated dibenzo-p-dioxins (PCDDs), -furans (PCDFs) and biphenyls (PCBs) form a group of ubiquitous environmental contaminants that persist in time, accumulate in a non-polar matrix as well as biomagnify in the trophic chain. Due to their hydrophobicity, they tend to accumulate in non-polar matrices such as sediment and sludge.
Since European legislation allows the use of sewage sludge, and bio-wastes in general, for application purposes on agricultural land, it is therefore of particular interest to verify the dioxin contamination in sludge, and biosolids alike. Current legislation is, however, scarce concerning the limit values of PCDD/Fs and dioxin-like (DL)-PCBs in sludge. Major EC regulations tend to focus on heavy metal pollution for these types of matrices. Although a 3rd working draft document4 exists (EC 2000), which proposes a limit of 100 ng I-TEQ kg-1 (dry weight). More recent publications report values that either comply with this limit for all samples5 or comply on average, the latter have maximum values going up to 250 pg PCDD/F's TEQ g-1 (dry weight) (TEF scheme not mentioned).
The clean-up and extraction procedure for both bio-analytical and chemo-analytical methods has been described elsewhere. This procedure with small modifications will allow comparison between virtually identical extracts by both the CALUX (Chemically activated luciferase gene expression) bioassay and GC-IDHRMS (Gas Chromatography - Isotope Dilution High Resolution Mass spectrometry) analysis. A soft extraction method, to mimic weathering processes and obtain a bioavailable fraction, can then be used to assess the impact on human dietary intake by common fertilization practices11 in the future.
Since European legislation allows the use of sewage sludge, and bio-wastes in general, for application purposes on agricultural land, it is therefore of particular interest to verify the dioxin contamination in sludge, and biosolids alike. Current legislation is, however, scarce concerning the limit values of PCDD/Fs and dioxin-like (DL)-PCBs in sludge. Major EC regulations tend to focus on heavy metal pollution for these types of matrices. Although a 3rd working draft document4 exists (EC 2000), which proposes a limit of 100 ng I-TEQ kg-1 (dry weight). More recent publications report values that either comply with this limit for all samples5 or comply on average, the latter have maximum values going up to 250 pg PCDD/F's TEQ g-1 (dry weight) (TEF scheme not mentioned).
The clean-up and extraction procedure for both bio-analytical and chemo-analytical methods has been described elsewhere. This procedure with small modifications will allow comparison between virtually identical extracts by both the CALUX (Chemically activated luciferase gene expression) bioassay and GC-IDHRMS (Gas Chromatography - Isotope Dilution High Resolution Mass spectrometry) analysis. A soft extraction method, to mimic weathering processes and obtain a bioavailable fraction, can then be used to assess the impact on human dietary intake by common fertilization practices11 in the future.
Boek: International Symposium on Halogenated Persistent Organic Pollutants
Volume: 74
Pagina's: 206-209
Aantal pagina's: 4
Jaar van publicatie:2012
Trefwoorden:PCDD/Fs, dioxin-like PCBs, Sludge, Biowaste, Chemically Activated LUciferase gene eXpression, GC-IDHRMS, Agricultural land application