北京城区大气中有机溴污染物的分析

Analysis on the Organic Bromine in the Atmosphere in Beijing

利用仪器中子活化(INAA)法分析了2004年4月至12月间北京城区大气中气态与总悬浮颗粒物(TSP)样品中可萃取有机溴污染物(EOBr)和持久性可萃取有机溴污染物(EPOBr)的浓度.结果表明,采样期间城区大气中气态EOBr平均浓度为6.2 ng/m3(1.0～18.5 ng/m3),EPOBr平均浓度为0.95 ng/m3(0.02～2.2 ng/m3);TSP中EOBr和EPOBr的平均浓度分别为18.3 ng/m3(2.3～73.4 ng/m3)和1.0 ng/m3(0.09～3.0 ng/m3);气态和TSP中EPOBr分别占EOBr的15.3%(1.9%～62.8%)和5.5%(0.8%～55.6%).可见大气中的有机溴污染物绝大多数为酸溶或酸不稳定的化合物.

Gaseous and particulate phase samples are simultaneously collected at a downtown site in Beijing from April 2004 to December 2004 using a modified high-volume air sampler and determined by in strumental neutron activation analysis （INAA） for the concentrations of extractable organic-bromine （EOBr） and extractable persistent organic-bromine（EPOBr）. Results show that the average concentrations of EOBr are 6.2 ng/m^3（1.0～18.5 ng/m^3） and 18.3 ng/m^3（2.3～73.4 ng/m^3） in gaseous and particulate phase, respectively; the average concentrations of EPOBr are 0.95 ng/m^3 （0.02～2.2 ng/m^3） and 1.0 ng/m^3 （0.09～3.0 ng/m^3） in gaseous and particulate phase; EPOBr accounts for 15.3%（1.9%～62.8%）in gaseous phase and 5.5%（0.8%～55.6%） in TSP of total EOBr.