罗时江中5种环境内分泌干扰物的分布特征

以典型的农业面源污染河流——大理洱海罗时江作为研究对象,采用固相萃取、超声萃取和气相色谱质谱联用技术,对河流水体和表层沉积物样品中5种EDCs〔环境内分泌干扰物,包括BPA(双酚A)、E1(雌酮)、E2(17β-雌二醇)、EE2(乙炔基雌二醇)和E3(雌三醇)〕进行分析测定.结果表明,罗时江水体中普遍存在EDCs,其中ρ(BPA)为1.01～43.64 ng/L,ρ(E1)为2.54～20.53 ng/L,ρ(E2)为nd～23.18 ng/L,ρ(EE2)为1.16～13.74 ng/L,ρ(E3)为nd～26.55 ng/L.各采样点EDCs污染通量结果显示,右所、邓川2个乡镇对EDCs污染贡献量最为显著,之后由于湿地截留以及河流的自净作用EDCs污染通量有所削减.罗时江对洱海的入湖EDCs贡献量为1.35～3.70μg/s.在城镇下游处沉积物中E1和E3的富集倍数均为各采样点中最高,这与河流水体中的污染通量变化趋势一致,进一步说明该处污染负荷的加剧,并且说明EDCs会在污染发生时于下游就近沉积.沉积物中w(E3)最高(1.48～28.44μg/kg),其次为w(E1)(0.36～2.95μg/kg),E2因迅速降解不易富集. 

Distribution Characteristics of Five Endocrine Disrupting Chemicals in Luoshi River

The distribution characteristics of five Endocrine Disrupting Chemicals(EDCs) in Luoshi River,a river in a typical rural nonpoint pollution watershed in Dali’s Erhai Lake,were studied by solid phase extraction(SPE),ultrasonic extraction and gas chromatography mass spectrometry.The results indicated that EDCs were widely distributed in Luoshi River.The mass concentrations of bisphenol A(BPA),ethinyl estradiol(EE2),estrone(E1),estradiol(E2) and estriol(E3) in the river were 1.01-43.64 ng/L,1.16-13.74 ng/L,2.54-20.53 ng/L,nd-23.18 ng/L and nd-26.55 ng/L,respectively.Considering the total amount of EDCs pollution,it was shown that two major towns,Yousuo and Dengchuan,contributed the largest amount of EDCs,and the EDCs were reduced as a result of wetland intercepts and the stream’s self-purification.Luoshi River imported EDCs into Erhai Lake at a rate of 1.35-3.70 μg/s.The highest enrichment of E1 and E3 occurred downstream of the urban area,which was consistent with the total amount of EDCs.The analysis indicated that EDCs were deposited nearby rather than carried downstream.Among all the detected EDCs in the sediments,w(E3) showed the largest amount(1.48-28.44 μg/kg),followed by w(E1)(0.36-2.95 μg/kg).E2 was not easily enriched because of its rapid degradation.