Parallel Sampling for Dioxins Using Various Sampling Techniques At a Swedish Municipal Solid Waste Incinerator

Abstract

Parallel sampling was carried out in a Swedish municipal solid waste (MSW) incinerator, on two consecutive days, with five different sampling techniques. The samples were analysed for chlorinated dioxins (PCDDs) and chlorodibenzofurans (PCDFS) at two laboratories, one in Sweden and the other in Germany. Two different spiking protocols were used, both including pre-sampling or clean-up spikes from each homolog group of the tetra to octa CDDs and CDFs. Comparable results were obtained for all five sampling methods for the emission data and the recoveries for all pre-sampling spikes were above 50%. The agreement between the two laboratories was good. The different sampling methods resulted in very similar congener distributions (congener profiles) or isomer distributions (isomer patterns). However, the sampling techniques differ considerably in the distribution of PCDDs/PCDFs in various sampling compartments, The sampling techniques where large contribution of PCDDs and PCDFs could be found in the wash solvent may suffer from losses and/or cross-contamination problems unless the washing is carried out properly. The use of a cooled probe in combination with an adsorption (polyurethane foam plug) or absorption (ethoxyethanol) trap, where the main portion of the PCDDs and PCDFs were found in the condensate, is considered as a convenient and efficient sampling technique.