Abstract. This study presents novel multi-year monitoring data on atmospheric polybrominated diphenyl ethers (PBDEs) in Central Europe. Air was sampled on a weekly basis at a background site in the central Czech Republic from 2011 to 2014 (N = 114). Σ9PBDEs (without BDE209) total (gas and particulate) concentrations ranged from 0.088 to 6.08 pg m−3, while BDE209 was at 0.05–5.01 pg m−3. BDE47, BDE99 and BDE183 were the major contributors to Σ9PBDEs. The inverse of ambient temperature was positively correlated with the total concentrations of BDE47 and BDE66 while negative correlations were observed for BDE153 and BDE154. Overall, the atmospheric concentrations of individual PBDEs were controlled by primary emissions, re-volatilisation from surfaces, deposition processes and long-range atmospheric transport. Regarding gas-particle partitioning, with the exception of BDE28 (gaseous) and BDE209 (particulate), all congeners were consistently detected in both phases and clear seasonal variations were observed. For example, while the average measured particulate fraction (θmeasured) of BDE47 was 0.52 in winter, this was only 0.01 in summer. Similarly, for BDE99, θmeasured was 0.88 in winter, while it was only 0.18 in summer. The observed gas-particle partitioning coefficient (Kp, in m3 μg−1) was compared with three model predictions, assuming equilibrium or steady-state. None of the models could provide a satisfactory prediction of the partitioning, suggesting the need for a universally applicable model. Statistically significant decreases of the atmospheric concentrations during 2011–2014 were found for BDE100, 99, 153 and 209. Estimated apparent atmospheric halving times for these congeners were ranging from 2.6 (BDE209) to 4.5 (BDE153) years. Significant increases of BDE28 and 66 were observed for autumn and summer, respectively. This may suggest the accumulation of these persistent products in the environment due to photolytic conversion of higher brominated congeners.
Are atmospheric PBDE levels declining in Central Europe?
Examination of the seasonal variations, gas-particle partitioning and
implications for long-range atmospheric transport
