Novel brominated flame retardants (NBFRs) in soil and moss in Mt. Shergyla, southeast Tibetan Plateau: Occurrence, distribution and influencing factors

• Published in: Environmental pollution (1987) Vol. 291; p. 118252
• Main Authors: Xian, Hao, Hao, Yanfen, Lv, Jingya, Wang, Chu, Zuo, Peijie, Pei, Zhiguo, Li, Yingming, Yang, Ruiqiang, Zhang, Qinghua, Jiang, Guibin
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.12.2021
• Subjects: Alpine region; Long-range atmospheric transport (LRAT); Novel brominated flame retardant; Persistent organic pollutants (POPs); Tibetan plateau; Alpine region; Tibetan plateau; Novel brominated flame retardant; Long-range atmospheric transport (LRAT); Persistent organic pollutants (POPs)
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2021.118252

Research on the environmental fate and behavior of novel brominated flame retardants (NBFRs) remains limited, especially in the remote alpine regions. In this study, the concentrations and distributions of NBFRs were investigated in soils and mosses collected from two slopes of Shergyla in the southeast of the Tibetan Plateau (TP), to unravel the environmental behaviors of NBFRs in this background area. The total NBFR concentrations (∑7NBFRs) ranged from 34.2 to 879 pg/g dw in soil and from 72.8 to 2505 pg/g dw in moss. ∑7NBFRs in soil samples collected in 2019 were significantly higher than those in 2012 (p < 0.05). Decabromodiphenyl ethane (DBDPE) was the predominant NBFR, accounting for 90% of ∑7NBFRs on average. The ratio of the concentrations in moss and soil showed significantly positive correlations with LogKOA except for DBDPE (p < 0.05), indicating that the role of mosses as accumulators compared to soils are more pronounced for more volatile NBFRs. In addition, the concentrations of NBFRs generally decreased with increasing altitude on the south-facing slope, whereas on the north-facing slope some NBFRs exhibited different trends, suggesting concurrent local and long-range transport sources. Normalization based on total organic carbon/lipid concentrations strengthened the correlation with altitude, implying that the altitude gradient of the mountain slope and forest cover could jointly affect the distribution of NBFRs in the TP. Furthermore, principal components analysis (PCA) with multiple linear regression analysis (MLRA) showed that the average contribution of the mountain cold trapping effect (MCTE) accounted for the major (77%) contribution and forest filter effect (FFE) has only a modest contribution to the deposition of NBFRs in soil. [Display omitted] •Occurrence of NBFRs was investigated in soils and mosses in the Tibetan Plateau.•DBDPE was the dominant NBFR contaminant in all samples.•NBFRs with higher values of logKOA accumulated more in mosses.•The distribution of NBFRs was jointly affected by altitude and forest cover.•Local and LRAT sources of NBFRs may cause altitudinal distribution discrepancies.