Spatial Distribution of Halogenated Flame Retardants in Mosses and Lichens of South Shetland Islands, Antarctica

Abstract

We investigated the spatial distribution of halogenated flame retardants (HFRs), including polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), and emerging flame retardants, dechlorane plus (DP) and related compounds (dechloranes), in the South Shetland Islands in Antarctica using mosses and lichens as bioindicators. The sampled species included 2 mosses (Andreaea depressinervis and Sanionia uncinata) and 2 lichens (Himantormia lugubris and Usnea antarctica). PBDEs were detected in all the samples and their levels ranged between 3.18-71.5 pg/g in the mosses and 1.51-188 pg/g in the lichens. The concentration of HBCD ranged between 0.63-960 pg/g in the mosses and 0.13-21.1 pg/g in the lichens. The levels of dechloranes ranged between 2.04-2400 pg/g in the mosses and 1.04-83.8 pg/g in the lichens. HFRs were detected in all samples from the South Shetland Islands, suggesting the long-range atmospheric transport (LRAT) of the HFRs. In addition, the highest HFR contamination near the King Sejong Station and the Captain Arturo Prat Base implied that the Antarctic research stations acted as local HFR sources. The HFR levels and distribution patterns of these compounds at the Narebski Point and in the wet lowlands suggested that penguin colonies and melting ice water might be secondary HFR sources in Antarctica. The HFR levels differed by plant species, even at the same sampling site, so further research on the factors associated with HFR accumulation is necessary. This study depicted the spatial distribution of HFR levels in the South Shetland Islands, Antarctica and identified the possible HFR sources and differences in HFR accumulation among plants, which could aid our understanding of the sources, transports, and fates of HFRs and the potential ecological effects of HFR contamination in Antarctica.