青岛近海PCDD/Fs的沉积通量、毒性当量及来源

用高分辨率气相色谱-质谱方法对青岛胶州湾内外表层沉积物、柱状岩心及贻贝样品中的17种毒性多氯代二苯并二 /呋喃(PCDD/Fs)进行了分析和讨论.表层沉积物的SP_4-8CDD/Fs含量范围在11.6～369pg/g dw,主要以P_4-8CDFs为主.S2,3,7,8-PCDD/Fs含量范围4.1～232.4pg/g dw.在环流作用下沉积物中形成了明显的东-西分布格局.除河口处外,PCDD/F同系物分布基本上相同,即低氯代PCDD/Fs占主导.SP_4-8CDD/Fs沉积通量从1951年起逐渐增大,STEQ沉积通量从1980年显著增大.青岛近海PCDD/Fs的来源相对恒定,推测为城市污水污泥和大气沉降.贝肉中S2,3,7,8-PCDD/Fs为2.9～5.1pg/g dw. TEQ的主要来源为2,3,4,7,8-PeCDF(35%)、2,3,7,8-TCDF(30%)、2,3,7,8,-TCDD(30%).

Investigation of sedimentation fluxes, TEQ and sources of PCDD/Fs in Qingdao coastal sea

kinds of toxic PCDD/Fs in surface sediments, sediment core and mussels in Qingdao coastal sea of Jiaozhou Bay were analyzed and discussed with HRGC-HRMS technique. The sediment content of P4-8CDD/Fs was 11.6~ 369pg/g dw, dominated by P4-8CDFs, and that of 2,3,7,8-substituted PCDD/Fs was 4.1~232.4pg/g dw. The sediment formed obviously east-west distribution pattern under the action of cycle-flow. Except for the river mouth, the distribution of PCDD/F congeners was same basically with the lower chlorinated congeners dominated. The fluxes of SP4-8 CDD/Fs increased gradually since 1951 and STEQ fluxes increased significantly since 1980. The sources of PCDD/Fs in Qingdao coastal sea were constant relatively and were guessed to be the sewage sluge and atmospheric deposition. The S2,3,7,8-substituted PCDD/Fs in the mussels were 2.9~5.1pg/g dw. The main sources of TEQ were 2,3,4,7,8-PeCDF(35%), 2,3,7,8-TCDF(30%), 2,3,7,8,-TCDD(30%).