title: Mono- to Octa-chlorinated PCDD/Fs in stack gas from typical waste incinerators and their implications on emission.
abstract: Mono- to octa-chlorinated dibenzo-p-dioxins and dibenzofurans (mono- to octa-CDD/Fs) were determined in 14 stack gas samples from two municipal solid waste incinerators and two medical waste incinerators. The total PCDD/F concentrations were 5.1-390 ng/Nm(3), and the mono- to trichlorinated homologues contributed 53.2-94.5% of the total concentrations. The homologue profiles were dominated by the MoCDF, ranged from 1.51 to 113.1 ng/Nm(3), and the proportion that each PCDF homologue group contributed to the total concentration decreased with increasing chlorination level. The toxic equivalent concentrations (I-TEQs) were 0.01-2.81 ng I-TEQ/Nm(3), with 2,3,4,7,8-PeCDF being the biggest contributor, at 30.6-60.0%. Correlations were found among the PCDD/PCDF ratios (D/F ratios), the degree of chlorination, and the TEQ. Stack gases with low I-TEQs had higher proportions of the less chlorinated homologues and lower D/F ratios, which could be attributed to the removal of the more chlorinated isomers by the air pollution control systems used by the incinerators. 2,8-DiCDF, 2,4,8-TrCDF, DiCDF, and TrCDF can be used as TEQ indicators for monitoring PCDD/Fs. 2,8-DiCDF and 2,4,8-TrCDF correlated well with the TEQ because they strongly correlated with 2,3,4,7,8-PeCDF, implying possible correlations in their formation mechanisms.
authors.affiliation: State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences , P.O. Box 2871, Beijing 100085, China. liuwb@rcees.ac.cn
authors.forename: Wenbin
authors.initials: W
authors.lastname: Liu
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Tian
authors.forename: Haifeng
authors.initials: H
authors.lastname: Li
authors.forename: Huiting
authors.initials: H
authors.lastname: Xie
authors.forename: Ke
authors.initials: K
authors.lastname: Xiao
authors.forename: Changliang
authors.initials: C
authors.lastname: Li
authors.forename: Chen
authors.initials: C
authors.lastname: Tang
authors.forename: Minghui
authors.initials: M
authors.lastname: Zheng
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D001572:Benzofurans / Q000032:analysis*; D002681:China; D000072338:Dibenzofurans, Polychlorinated; D004147:Dioxins / Q000032:analysis*; D004784:Environmental Monitoring; D006843:Hydrocarbons, Chlorinated / Q000032:analysis; D017745:Incineration; D008506:Medical Waste / Q000032:analysis; D062611:Solid Waste / Q000032:analysis
chemical_list: D000393:Air Pollutants; D001572:Benzofurans; D000072338:Dibenzofurans, Polychlorinated; D004147:Dioxins; D006843:Hydrocarbons, Chlorinated; D008506:Medical Waste; D062611:Solid Waste