珠江河流胶体中的典型内分泌干扰物

采用切向流超滤、固相萃取、气相色谱-质谱联用等分离和分析方法,研究了珠江2条河流中典型内分泌干扰物(EDCs)在胶体相中的含量分布、胶体/水相间的分配作用.结果发现:胶体中4-壬基酚(NP)、双酚A(BPA)、雌酮(E1)的含量范围分别为23.2~108ng/L、2.3~97.6ng/L、n.d.(未检出)~0.32ng/L,平均值分别为70,31.4,0.3ng/L;17β-雌二醇(E2)、己烯雌酚(DES)、17α-乙炔雌二醇(EE2)、雌三醇(E3)则未在胶体样品中检出.除石龙外,其余各采样点表、底水层间的胶体EDCs浓度水平无显著差异.NP和BPA含量与胶体有机碳(COC)含量、紫外吸收强度(UV254)均呈正相关,说明COC是控制酚类雌激素在胶体相中分布的一个重要因素,NP、BPA和COC之间的相互作用与胶体有机碳的芳香性有关.计算发现,珠江河水中约21%~67%的NP、4%~74%的BPA、24%~26%的E1存在于胶体相,NP和BPA在胶体/水相间的有机碳归一化分配系数(Kcoc)分别为10(5.69±0.50)、10(5.51±0.77),高出各自的悬浮颗粒物/水分配系数(Koc)1个数量级,表明胶体的强吸附能力对EDCs在水环境介质间分配、迁移、转化发挥了重要作用.

Occurrence of colloid-bound endocrine-disrupting chemicals in the Pearl River,China

The occurrence of typical endocrine-disrupting chemicals (EDCs) binding to colloids in the two rivers of Pear River system, and their partitioning between colloidal and water soluble phases were studied with the applications of cross-flow ultrafiltration, solid phase extraction and gas chromatography-mass spectrometry. It was found that the concentrations of 4-nonylphenol (NP), bisphenol A (BPA) and estrone (E1) ranged in 23.2~108ng/L, 2.3~97.6ng/L, n.d. (not detected)~0.32ng/L, with mean values of 70ng/L, 31.4ng/L and 0.3ng/L, respectively. 17β-estradiol (E2), diethylstilbestrol (DES), 17α-ethynylestradiol (EE2) and estriol (E3) were not detected in all samples. There was no obvious variation of EDC concentrations between the surface and bottom water samples, except for the samples collected from Shilong. Moreover, it was observed that NP and BPA concentrations were both positively correlated with the colloidal organic carbon (COC) contents and the absorbance of UV (UV254), suggesting that COC was a key factor controlling the distribution of colloid-bound phenolic xenoestrogens, and the interaction between COC and these chemicals was related with the aromaticity. It was estimated that the percentage of colloid-bound EDCs varied 21%~67% for NP, 4%~74 % for BPA, and 24%~26% for E1, respectively. Additionally the colloidal organic carbon normalized partition coefficients (Kcoc) for NP (10(5.69±0.50)) and BPA (10(5.51±0.77)) were one order of magnitude higher than their suspended particle-water partition coefficients (Koc), indicating the powerful affinity of colloids played a critical role in partition, transportation and transformation of EDCs in the aquatic environment.