Onderzoek naar het voorkomen van gemengd broom/chloor dibenzo-p-dioxinen en furanen in emissies van een industrieel proces

Abstract

This report describes the results of the analysis of brominated and mixed halogenated (Br/Cl) dibenzo-p-dioxins and furans (DD/Fs) in the stack gas of an industrial process in which significant amounts of flame retardants are being used. Stack gas samples have been collected prior and following the after burner gas cleaning facility. PCDD/F levels, expressed in 2,3,7,8 TCDD toxic equivalents (TEQ), as analysed by TNO were 0.20 ng TEQ/m3 ind (before) and 0.05 ng TEQ/m3 ind (after), respectively. Using both negative chemical ionization (NCI) and electron impact (EI)-mass spectrometry, several brominated compounds were found and tentatively identified as bromobiphenyls (BrBs) and bromochloropolyaromatic hydrocarbons (Br/Cl-PAHs). In addition, some 28 monobromo-polychlorinated (Br/Cln, n=3-7) DD/Fs could be demonstrated in low concentrations in both samples. Determination of their isomeric structure failed due to low sample sizes. Estimation of their TEQ value was performed on the basis of the response ratio for monobroom-heptachloor DD/Fs (Br-Cl7-DD/F) and quantified polychloro analogues (Cl8D/F). Assuming a random distribution of the Bratom, and an estimated relative occurrence of Br to Cl of 1:1000 per substituent, the additional BrCln-DD/F TEQ value was estimated to be not greater than approximately 1% of the corresponding PSDD/F-TEQ value.