Brominated and Chlorinated Flame Retardants in Tree Bark from Around the Globe

Abstract

Brominated and chlorinated flame retardants were measured in about 40 samples of tree bark from 12 locations around the globe. The analytes were polybrominated diphenyl ethers (PBDE), Dechlorane Plus (DP), decabromodiphenylethane (DBDPE), hexabromocyclododecane (HBCD), hexabromobenzene (HBB), pentabromoethylbenzene (PBEB), pentabromobenzene (PBBz), and tetrabromo-p-xylene (pTBX). The highest concentrations of these compounds were detected at an urban site in Downsview, Ontario, Canada. Total PBDE and DP concentrations ranged from 2.1 to 190 ng/g lipid weight and from 0.89 to 48 ng/g lipid weight, respectively. Relatively high levels of DP (46 ± 4 ng/g lipid weight) were found at a remote site at Bukit Kototabang in Indonesia. The concentrations of total PBDE, DP, PBEB, and HBCD in the tree bark samples were significantly associated with human population in the nearby areas (r(2) = 0.21-0.56; P < 0.05). In addition, the concentrations of total PBDE and DP were significantly associated (r(2) = 0.40-0.64; P < 0.05). with the corresponding atmospheric concentrations of these compounds over a concentration range of 2-3 orders of magnitude.