In the present study, atmospheric particle samples were collected between September 2015 and February 2016 from Bizerte city (Tunisia) to investigate the occurrence, potential sources and impacts of a range of flame retardants (FRs), including hexabromocyclododecane diastereoisomers (HBCDDs), new halogenated flame retardants (NHFRs), as well as methoxylated polybrominated diphenyl ethers (MeO-BDEs). Among 19 examined compounds, 9 congeners (α-HBCDD, β-HBCDD, γ-HBCDD, HBB, DBDPE, syn-DP, anti-DP, 2′-MeO-BDE-68 and 6-MeO-BDE-47) were detected in atmospheric particles at different levels and frequencies. Overall, the average concentration of NHFRs (1.53 pg m−3) was 1.5 and 51 folds higher than that of HBCDDs (1.04 pg m−3) and MeO-BDEs (0.03 pg m−3), respectively. By comparison with other areas of the world, NHFRs and HBCDDs in Bizerte were at medium pollution level, while MeO-BDEs were at lower levels. No significant correlations were found between NHFR, HBCDD and MeO-BDE concentrations, suggesting different sources related on one hand to the biogenic origin of MeO-BDE, and on the other hand to various types and utilisations of imported NHFR- and HBCDD-containing products, as Tunisia does not manufacture FRs. DP and HBCDD diastereoisomer profiles appeared to be divergent from their commercial products, pointing out that a complex degradation or stereoselective transformation processes occurring in ambient air around Bizerte city. The estimated daily human exposure dose (DED) to particle-bound HBCDDs, NHFRs and MeO-BDEs via outdoor air inhalation was generally at low levels. Hence, this study reports for the first time the occurrence and potential impact of HBCDDs, NHFRs and MeO-BDEs in atmospheric particles from North Africa.
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