Emission of unintentionally produced persistent organic pollutants (UPOPs) from municipal waste incinerators in China Yuancheng Li 1 , Yang Yang 1 , Gang Yu, Jun Huang * , Bin Wang, Shubo Deng, Yujue Wang School of Environment, Beijing Key Laboratory for Emerging Organic Contaminants Control, State Key Joint Laboratory of Environment Simulation and Pollution Control (SKLESPC), Tsinghua University, Beijing 100084, China highlights graphical abstract  Level of PCDD/Fs, PCBs, PeCBz, and HxCBz in flue gas from MWI in China was reported.  Emission factors of PeCBz (144 mg/t) and HxCBz (84.7 mg/t) in flue gas from MWI were given.  Profiles of PCBs and dl-PCBs in both gaseous and fly ash phase were stated.  Removal efficiencies of PCDD/Fs, PCBs, PeCBz, and HxCBz by air pollution control device were evaluated. article info Article history: Received 23 February 2016 Received in revised form 11 May 2016 Accepted 12 May 2016 Available online 27 May 2016 Handling Editor: Myrto Petreas Keywords: MWI Emission PCDD/Fs PCBs PeCBz HxCBz abstract Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), pentachlorobenzene (PeCBz) and hexachlorobenzene (HxCBz), which are listed in the Stockholm Convention, are commonly known as unintentionally produced persistent organic pollutants (UPOPs). As municipal waste incinerators (MWIs) have burgeoned in China, the emission of UPOPs is of great con- cerns. Compared to the extensive studies of PCDD/Fs emission, not much information of non-dioxin UPOPs (i.e., PCBs, HxCBz, and PeCBz) is available. In the present study, samples from raw gas (RG) af- ter boiler, stack gas (SG) after air pollution control devices (APCDs) and fly ash (FA) samples were collected from typical MWIs in China. The analyses of SG samples indicate that PCDD/Fs are the major contributor to TEQ value, but non-dioxin UPOPs are the dominant compounds in terms of mass con- centration. The mean emission factors of dl-PCBs, PeCBz, and HxCBz in SG are 0.372, 144, and 84.7 mg/t, respectively. In contrast with gaseous samples, FA contains higher mass concentration of PCDD/Fs and PCBs than that of PeCBz and HxCBz. In terms of homologues distribution of PCBs, di- to tetra-CBs were the predominant species in both SG and FA samples. PCB-126 is the major contributor to the TEQ con- centration. The comparison of UPOPs composition in SG and RG samples shows that activated carbon adsorption process is capable of removing most PCDD/Fs, but less efficient for the removal of non-dioxin UPOPs. © 2016 Elsevier Ltd. All rights reserved. 1. Introduction Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/ Fs), polychlorinated biphenyls (PCBs), pentachlorobenzene (PeCBz) * Corresponding author. E-mail address: huangjun@tsinghua.edu.cn (J. Huang). 1 These authors contributed equally to this work and should be considered co- first authors. Contents lists available at ScienceDirect Chemosphere journal homepage: www.elsevier.com/locate/chemosphere http://dx.doi.org/10.1016/j.chemosphere.2016.05.037 0045-6535/© 2016 Elsevier Ltd. All rights reserved. Chemosphere 158 (2016) 17e23