Molecular-level evidence provided by ultrahigh resolution mass spectrometry for oil-derived doc in groundwater at Bemidji, Minnesota
Dissolved organic matter samples extracted from ground water at the USGS Bemidji oil spill site in Minnesota were investigated by ultrahigh resolution mass spectrometry. Principle component analysis (PCA) of the elemental composition assignments of the samples showed that the score plots for the contaminated sites were well separated from those for the uncontaminated sites. Additionally, spectra obtained from the same sampling site 7 and 19 years after the spill were grouped together in the score plot, strongly suggesting a steady state of contamination within the 12 year interval. The double bond equivalence (DBE) of Ox class compounds was broader for the samples from the contaminated sites, because of the complex nature of oil and the consequent formation of compounds with saturated and/or aromatic structures from the oxygenated products of oil. In addition, Ox class compounds with a relatively smaller number of x (x < 8; x = number of oxygen) and OxS1 class compounds were more abundant in the samples from the contaminated sites, because of the lower oxygen and higher sulfur contents of the oil compared to humic substances. The molecular-level signatures presented here can be a fundamental basis for in-depth analysis of oil contamination.
Citation Information
Publication Year | 2016 |
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Title | Molecular-level evidence provided by ultrahigh resolution mass spectrometry for oil-derived doc in groundwater at Bemidji, Minnesota |
DOI | 10.1016/j.jhazmat.2016.08.018 |
Authors | Ananna Islam, Arif Ahmed, Manhoi Hur, Kevin A. Thorn, Sunghwan Kim |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Journal of Hazardous Materials |
Index ID | 70178694 |
Record Source | USGS Publications Warehouse |
USGS Organization | Toxic Substances Hydrology Program; National Research Program - Central Branch |