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首页> 外文学位 >Interactions of polychlorinated biphenyls with the air, water, and sediments of the Delaware River Estuary.
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Interactions of polychlorinated biphenyls with the air, water, and sediments of the Delaware River Estuary.

机译：多氯联苯与特拉华河河口的空气，水和沉积物的相互作用。

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摘要

The cycling of polychlorinated biphenyls (PCBs) within the rural/urban/industrial Delaware River watershed was examined to establish mass loading rates for management purposes and to assess historic trends in PCB inputs and mobilization. Simultaneous measurements of PCBs in the air and water over the Delaware River Estuary were taken in support of the Total Maximum Daily Load (TMDL) process conducted by the Delaware River Basin Commission (DRBC). Gas-phase concentrations of SigmaPCBs ranged from 110-1350 ng m-3, while dissolved water concentrations were between 420 and 1650 ng L-1. Air-water gas exchange fluxes of SigmaPCBs showed net volatilization for all samples, with values ranging from 360-3000 ng m-2 d-1. There is a high degree of uncertainty associated with these flux estimates, but the direction of PCB movement (net volatilization from the water to the air) can be stated with 95% confidence for all but 16 congeners.; Sediment concentrations of PCBs were measured in the Estuary in order to understand PCB behavior over time from the sediment history, as well as to examine present-day PCB trends in surficial sediments. Peak SigmaPCB concentrations ranged between 250 and 2410 ng/g dry wt. and concentrations generally declined with proximity to the surface. The SigmaPCB concentrations found in the sediments of the Delaware are comparable in magnitude to those seen in Chesapeake Bay and showed declining trends similar to those found in the Great Lakes.; Indirect atmospheric deposition parameters for PCBs were calculated for watersheds in the Delaware River Estuary. Tributary PCB loads and atmospheric PCB concentrations were used to understand the pass-through efficiencies for nine rivers/creeks that appeared to be atmospherically driven. Pass-through efficiencies were ≤ 5% for PCB homologues 3-6, but ranged from 3-18% for homologue group 7 and 2-17% for homologue group 8. Thus, pass-through efficiencies increased with increasing chlorination, with a dropoff at the octachlorinated homologue. This trend suggests that transfer of PCBs from the atmosphere to the River via the watershed is more efficient for high molecular weight PCBs than for low molecular weight PCBs. These selected watersheds, therefore, may be at or close to equilibrium with respect to gaseous exchange of PCBs.
机译：对农村/城市/工业特拉华河流域内的多氯联苯（PCB）的循环进行了检查，以建立用于管理目的的质量装载率，并评估PCB投入和动员的历史趋势。同时对特拉华河口上空气和水中的PCBs进行了测量，以支持特拉华河流域委员会（DRBC）进行的总最大日负荷（TMDL）过程。 SigmaPCBs的气相浓度范围在110-1350 ng m-3之间，而溶解水的浓度在420和1650 ng L-1之间。 SigmaPCBs的空气-水气体交换通量显示所有样品的净挥发，其值在360-3000 ng m-2 d-1之间。这些通量估计值存在很大的不确定性，但是对于16个同类物，PCB的运动方向（从水到空气的净挥发）可以用95％的置信度表示。在河口中测量了PCBs的沉积物浓度，以便从沉积物历史中了解PCB在一段时间内的行为，并检查表层沉积物中当今PCB的趋势。 SigmaPCB的峰值浓度在250至2410 ng / g干重之间。并且浓度通常随着靠近表面而降低。特拉华州沉积物中发现的SigmaPCB浓度在数量上与切萨皮克湾相当，并且下降趋势与大湖地区相似。计算了特拉华河河口流域中PCBs的间接大气沉积参数。使用支流PCB负载和大气PCB浓度来了解似乎是由大气驱动的9条河流/溪流的通过效率。 PCB同系物3-6的通过效率为≤5％，但同系物7组的通过效率为3-18％，同系物8组的通过效率为2-17％。因此，通过效率随着氯化度的增加而增加，并且下降。在八氯同系物上。这种趋势表明，高分子量PCB的多氯联苯从大气经分水岭到河流的转移比低分子量PCB的转移更为有效。因此，这些选择的分水岭就PCB的气体交换而言可能处于平衡状态或接近平衡状态。

著录项

  • 作者

    Rowe, Amy Ann.;

  • 作者单位

    Rutgers The State University of New Jersey - New Brunswick.;

  • 授予单位 Rutgers The State University of New Jersey - New Brunswick.;
  • 学科 Environmental Sciences.
  • 学位 Ph.D.
  • 年度 2006
  • 页码 152 p.
  • 总页数 152
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 环境科学基础理论;
  • 关键词

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