| Persistent halogenated organic compounds are an international concern due to their environmental persistence, bioaccumulation, long distance migration and high toxicity. Poly chlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) have been banned, polybrominated diphenyl ethers (PBDEs) are still in use, and some new halogenated organic compounds such as dechlorane plus (DP), tetrabromo paraxylene (PTBX), pentabromophenyl (PBBz), pentabromotoluene (PBT) and hexabromobenzene (HBB) are some newly emerging. Researches on the organic halogen compounds in the bark focused on PBDEs, PCBs and OCPs, fewer reports was on DPs, and there are no reports of PTBX, PBBz, PBT, and HBB in the bark. Afew of domestic research was mainly focused on the eastern region, but the study of the western region is none.Levels of DL-PCBs, PBDEs, NBFRs, OCPs and DPs in the tree bark of Western China were n.d.～1.81 ng·g-1 1.w.,6.7～224 ng·g-11.w., 0.86～8.28 ng·g-1 1.w.,105～1024 ng·-1 1.w.和n.d.-3.32 ng·g-11.w., respectively. PCB-118 was the dominant congener of DL-PCBs, accounting for 70% of the total concentration. Principal component analysis showed that the source of DL-PCBs in the bark from western minority areas mainly came from atmospheric transport. BDE-209 was the dominant congener of PBDEs, accounting for 62.8～99.4% of the total concentration. The ∑PBDE concentrations in the samples from western minority areas were comparable with the concentrations found in tree bark samples from the Upper Yellow River area, but they were much lower than concentrations that have been found in tree bark samples from eastern and coastal areas of China. Four new brominated flame retardants (PTBX, PBBz, PBT, and HBB) were all detected except PTBX, with the detection rate of 93%, suggesting these four NBFRs are widespread in the western minority areas. Correlation analysis results showed that NBFRs have different sources with PBDEs, and under the influence of aluminum industry around. The average concentrations of DDTs, HCHs and HCB in the tree bark of Western China were 428 ng·g-1.w.,74 ng·g-11.w.和43 ng·g-1.w., respectively. Through the analysis of the characteristic value of HCHs and DDTs, there were new sources of input of p,p’-DDT and y-HCH in western minority areas. The DPs concentrations in the samples from western minority areas were comparable with the concentrations found in tree bark samples from the Upper Yellow River area, and the correlation analysis results showed that DPs and BDE-209 have the different source in western minority areas.At the same time, we used the bark-air model to estimate the organic halogen compounds concentrations in the atmosphere of the western minority areas. The levels of DL-PCBs, PBDEs, NBFRs, OCPs and DPs in the atmosphere were 0-0.79 pg/m3,0.05-6.85 pg/m3,0.64-5.45 pg/m3,114-1218 pg/m3 and 0-0.04 pg/m3, respectively. Compared with domestic and foreign researches, the HCHs and DDTs concentrations in the atmosphere of western minority areas were at higher levels, however, DL-PCBs, PBDEs, NBFRs and DPs concentrations were at lower levels.In addition, this study also deployed the PUF passive sampling paired with the bark sample and the comparing with the bark passive sampling have been made. And the results showed that as for organic halogen compounds with relatively high detection rate and concentration, especially more stable organic halogen compounds, tree bark passive sampling and PUF passive sampling have good parallelism. But organic halogen compounds with relatively low environment concentration and relatively high KOA value have differences between the two passive samplings.
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