Study On The Pollution Characteristics Of Pbdes In Atmosphere Of Harbin

Poly Brominated Diphenyl Ethers（PBDEs）are typical persistent organic pollutants in atmosphere,which have been attracted more attentions in the past decade in the world.As an important old industrial city in northeast China,Harbin has special climate conditions,which is important for the study of pollution characteristics and gas-particle partitioning of PBDEs in atmosphere.However,little information was available for this region.Therefore,the study was conducted for air sample collection and PBDEs analysis,which will provide new scientific contribution to this related field.Gas phase and particle phase air samples were collected by an active air sampler in urban region of Harbin from April 2016 to March 2017.Totally,11 PBDEs congeners were analyzed by GC-MS.PBDEs were frequently detected with non-uniform detection rate for different congeners.In gas phase,BDE-47 was the dominated congener.The average concentrations of the total PBDEs concentrations varied from 0.49 to 71.32 pg/m³,with more than two orders of magnitude.In particle phase,the dominated congener was BDE-209,with the average concentration of 69 pg/m³ for BDE-209.In general,there are more than two orders of magnitude with concentrations among different congeners for both gas and particle phase,which indicated the wide pollution status of PBDEs in air.For the total concentration（gas plus particle）of PBDEs,it was found that BDE-209was the dominated congener.The contribution of BDE-209 toΣ₁₁PBDEs was higher than80%,which was comparable with other previous studies.The concentration ofΣ₁₁PBDEs in atmosphere in Harbin varied from 3.83 to 318.16 pg/m³.Different seasonal variations with PBDEs concentrations were found for gas phase and particle phase.It was found that temperature and wet deposition were the important factors affecting the concentration of PBDEs in the atmosphere in Harbin.Based on measurement,the G/P partitioning of PBDEs in Harbin was comprehensively studied based some classic gas-particle partitioning theories.Both the equilibrium-state model and the steady-state model were applied in this study.The results indicated that significant linear regression was found between log Kp and log P_L,and between log Kp and log K_OA,with the p<0.01.The results were similar to those of previous studies.According to the theory of G-P partitioning in equilibrium state,the obtained slopes with the regression between log Kp and log P_L,and the regression between log Kp and log K_OA,both indicated that PBDEs were not reached equilibrium between gas phase and particle phase in atmosphere in Harbin.For the equilibrium state equation(log K_PE),the gas-particle partitioning calculated from the actual monitoring data of PBDEs in Harbin atmosphere are not in good agreement with the predication with the difference bigger than 1 order of magnitude,when the values of log P_L less than-7 or their log K_OA higher than 13.For the steady state equation(log K_PS),the gas-particle partitioning calculated from the actual monitoring data of PBDEs in Harbin atmosphere are in good agreement with the predication with the difference less than 1 order of magnitude.In summary,the G/P partitioning equation based on steady state equilibrium state is superior to the equilibrium state based equation in describing the G/P partitioning behavior of PBDEs in atmosphere in Harbin for all congeners with any values of log K_OA.