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Long-term trends in atmospheric concentrations of pesticides, PCBs, and PAHs near the Great Lakes.

机译：大湖区附近农药，PCB和PAH的大气浓度的长期趋势。

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摘要

We used concentration data from the Integrated Atmospheric Deposition Network (IADN) to explore the spatial and long-term temporal trends, as well as loadings, of polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and several organochlorine pesticides in air near the Great Lakes. Results indicated that while the concentrations of most banned compounds have declined, urban effects can still be seen for PCBs and PAHs. Recent basinwide loadings estimates indicated that for hexachlorocyclohexanes (HCHs) and PCBs, inputs and releases of these compounds to and from the lakes, respectively, were decreasing over time.; In a more detailed study, we compared atmospheric concentrations of PAHs, PCBs, and several pesticides at Brule River, WI and Eagle Harbor, MI, two rural sampling sites on Lake Superior. Day-by-day regression analyses of the data showed that PAH concentrations, an indication of urban contamination, were significantly higher at Brule River than Eagle Harbor. Based on wind patterns, proximity to other cities, and further analyses, we concluded that pollution from Duluth, MN, a nearby industrial city, is influencing PAH concentrations at Brule River.; Temporal trends in gas-phase PCBs near Lakes Michigan and Superior were also studied in greater detail. Decreasing trends were found at both sites, but half-lives estimated from a first-order rate constant were four times as long as those found in previous studies. When historical data were added to the IADN data, the half-lives decreased and agreed well with half-lives in other environmental compartments. A similar, historical analysis of α- and γ-HCH data indicated that IADN data were the best predictor of trends.; We also investigated the causes of variability in gas-phase PCB and pesticide concentrations measured near Lakes Michigan, Superior, and Erie. A multiple linear regression model that incorporates temperature and time was used along with autocorrelation analyses of the residuals. Similar environmental behaviors were seen for most banned compounds, while an agricultural application cycle was present in the residual data for γ-HCH. PCBs and hexachlorobenzene showed strong residual autocorrelation patterns near Lake Michigan of an unknown origin.
机译：我们使用来自综合大气沉积网络（IADN）的浓度数据来探索附近空气中多氯联苯（PCB），多环芳烃（PAH）和几种有机氯农药的空间和长期时间趋势以及负荷五大湖。结果表明，尽管大多数违禁化合物的浓度下降了，但多氯联苯和多环芳烃的城市影响仍然可见。最近对整个盆地的装载量的估算表明，对于六氯环己烷和六氯苯，随着时间的推移，这些化合物向湖泊的输入和释放分别减少。在更详细的研究中，我们比较了威斯康星州布鲁尔河和密歇根州苏必利尔湖的两个农村采样点的大气中PAHs，PCBs和几种农药的浓度。数据的逐日回归分析显示，布鲁尔河的多环芳烃浓度（表明城市污染）明显高于鹰港。根据风向，与其他城市的距离以及进一步的分析，我们得出结论，附近工业城市明尼苏达州德卢斯的污染正在影响布鲁尔河的PAH浓度。还对密歇根湖和苏必利尔湖附近的气相多氯联苯的时间趋势进行了更详细的研究。在两个地点都发现下降趋势，但是根据一阶速率常数估计的半衰期是以前研究中发现的四倍。将历史数据添加到IADN数据后，其半衰期减少了，并且与其他环境分区的半衰期吻合得很好。对α-和γ-HCH数据的类似历史分析表明，IADN数据是趋势的最佳预测指标。我们还调查了密西根湖，苏必利尔湖和伊利湖附近测得的气相PCB和农药浓度变化的原因。结合温度和时间的多元线性回归模型与残差的自相关分析一起使用。对于大多数禁用化合物，也观察到类似的环境行为，而γ-六氯环己烷的残留数据中存在农业应用周期。多氯联苯和六氯苯在未知来源的密歇根湖附近显示出很强的残留自相关模式。

著录项

  • 作者

    Buehler, Stephanie S.;

  • 作者单位

    Indiana University.;

  • 授予单位 Indiana University.;
  • 学科 Environmental Sciences.
  • 学位 Ph.D.
  • 年度 2003
  • 页码 175 p.
  • 总页数 175
  • 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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