Civil and Environmental Engineering Department, University of Houston, 4800 Calhoun Road, Houston, TX 77204-4003, USA.
Chemosphere. 2010 Jun;80(2):100-12. doi: 10.1016/j.chemosphere.2010.04.014.
An on-going study in the Houston Ship Channel (HSC) characterized polychlorinated biphenyl (PCB) levels in sediment, water, and tissue in 2002-2003 and 2008. The observed PCB concentration ranges in all media were higher than those measured in other PCB-impacted water bodies in the world, with the highest concentrations occurring within the industrialized segments. Contrary to polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDD/PCDF) observations, the PCB concentrations in the dissolved phase were greater than the suspended phase. Possible explanations include passage of colloids, competition for adsorption sites from other hydrophobic contaminants, and continuing current sources. The PCB homologue distributions were similar for suspended water, sediment and tissue with the profile normalized around penta-chlorobiphenyls, while the dissolved phase profile normalized around tri-chlorobiphenyls. PCB-209 was detected in the suspended water phase and in sediment (10%) prompting interest into its sources to the HSC since PCB-209 was present only in rare commercial mixtures and is a byproduct in very few manufacturing processes. Inter-media analyses showed a significant correlation and transfer of PCBs. Dioxin-like PCBs contributed significant toxicity to total equivalent in tissue (33%), while they were insignificant in water (<10%) and sediment (<5%). The PCB concentrations over time showed a significant decrease in suspended water, sediment and tissue, while dissolved water concentrations showed insignificant change. The homolog distribution, however, showed a significant change in dissolved water and fish, a minor change in sediment and insignificant change in suspended water. Furthermore, an analysis for six representative congeners showed that they were accurate in predicting the total PCB concentrations and could be thus used as indicator PCBs.
一项正在休斯顿航道（HSC）进行的研究，对 2002-2003 年和 2008 年期间的沉积物、水和组织中的多氯联苯（PCB）水平进行了特征描述。在所有介质中观察到的 PCB 浓度范围都高于世界上其他受 PCB 影响的水体，浓度最高的区域出现在工业化区域。与多氯二苯并对二恶英/多氯二苯并呋喃（PCDD/PCDF）的观测结果相反，溶解相中的 PCB 浓度大于悬浮相。可能的解释包括胶体的传递、与其他疏水性污染物竞争吸附位点，以及持续的电流源。悬浮水、沉积物和组织中的 PCB 同系物分布相似，形态归一化为五氯联苯，而溶解相形态归一化为三氯联苯。在悬浮水相和沉积物（10%）中检测到 PCB-209，这引起了对 HSC 中 PCB-209 来源的兴趣，因为 PCB-209 仅存在于罕见的商业混合物中，并且在极少数制造过程中是副产品。介质间分析表明 PCBs 具有显著的相关性和传递性。类似二恶英的 PCBs 对组织中的总等效毒性（33%）有显著贡献，而在水中（<10%）和沉积物（<5%）中则不显著。随时间推移，悬浮水中的 PCB 浓度、沉积物和组织中的 PCB 浓度均显著下降，而溶解水中的 PCB 浓度则无显著变化。然而，同系物分布在溶解水中和鱼类中显示出显著变化，在沉积物中略有变化，在悬浮水中则无显著变化。此外，对六种代表性同系物的分析表明，它们可以准确预测总 PCB 浓度，因此可以用作指示性 PCB。
