Department of Chemical and Biomolecular Engineering, Clarkson University, 8 Clarkson Avenue, Potsdam, New York 13699, United States.
Center for Air Resources Engineering and Science, Clarkson University, 8 Clarkson Avenue, Potsdam, New York 13699, United States.
Environ Sci Technol. 2020 Nov 17;54(22):14352-14360. doi: 10.1021/acs.est.0c03825. Epub 2020 Oct 26.
Legacy halogenated contaminants have been monitored in the Great Lakes for decades, but there are many additional unknown halogenated contaminants potentially affecting the Great Lakes ecosystem. To address this concern, lake trout () were collected in 2005/2006 and 2015/2016 from each lake and screened for previously unidentified compounds. The isotopic profile deconvoluted chromatogram algorithm was used to isolate unknown halogenated components using high-resolution mass spectrometry data files generated by an atmospheric pressure gas chromatography-quadrupole time-of-flight mass spectrometer operated in positive and negative modes. The temporal and spatial differences in the newly detected features were used to isolate new potential contaminants. Decadal differences in the unknown halogenated compounds (or features) were compared with the total polychlorinated biphenyl concentration trends. Greater than 2000 unknown halogenated features were detected. As expected, Lake Superior contained the lowest number of unknown halogenated features, whereas Lake Ontario contained the highest. Unknown features tended to have fewer Cl and/or Br atoms compared to traditional legacy contaminant features typically monitored. Diverse patterns of unknown halogenated compounds between lakes suggested that there continues to be unidentified sources of halogenated contaminants in the Great Lakes missed by current monitoring programs.
数十年来，人们一直在对大湖中的传统卤代污染物进行监测，但仍有许多其他未知的卤代污染物可能对大湖生态系统造成影响。为了解决这一问题，我们于 2005/2006 年和 2015/2016 年从每个湖中采集了湖鳟鱼样本，并对以前未识别的化合物进行了筛选。我们使用同位素轮廓解卷积色谱算法，利用大气压气相色谱-四极杆飞行时间质谱仪在正、负模式下生成的高分辨率质谱数据文件，分离未知卤代成分。利用新检测到的特征的时间和空间差异来分离新的潜在污染物。我们将新发现的未知卤代化合物（或特征）的年代差异与总多氯联苯浓度趋势进行了比较。共检测到 2000 多种未知卤代特征。不出所料，苏必利尔湖含有的未知卤代特征数量最少，而安大略湖含有的数量最多。与通常监测的传统卤代污染物特征相比，未知特征通常含有较少的 Cl 和/或 Br 原子。不同湖泊之间未知卤代化合物的不同模式表明，当前的监测计划仍遗漏了大湖中卤代污染物的一些未知来源。
