Journal Article

Chemical Composition and Potential Environmental Impacts of Water-Soluble Polar Crude Oil Components Inferred from ESI FT-ICR MS

Liu, Yina, Kujawinski, Elizabeth B.

2015

Overview

Polar petroleum components enter marine environments through oil spills and natural seepages each year. Lately, they are receiving increased attention due to their potential toxicity to marine organisms and persistence in the environment. We conducted a laboratory experiment and employed state-of-the-art Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) to characterize the polar petroleum components within two operationally-defined seawater fractions: the water-soluble fraction (WSF), which includes only water-soluble molecules, and the water-accommodated fraction (WAF), which includes WSF and microscopic oil droplets. Our results show that compounds with higher heteroatom (N, S, O) to carbon ratios (NSO:C) than the parent oil were selectively partitioned into seawater in both fractions, reflecting the influence of polarity on aqueous solubility. WAF and WSF were compositionally distinct, with unique distributions of compounds across a range of hydrophobicity. These compositional differences will likely result in disparate impacts on environmental health and organismal toxicity, and thus highlight the need to distinguish between these often-interchangeable terminologies in toxicology studies. We use an empirical model to estimate hydrophobicity character for individual molecules within these complex mixtures and provide an estimate of the potential environmental impacts of different crude oil components.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Acids / Bioaccumulation / Biodegradation / Chemical analysis / Chemical composition / Cold Climate / Crude oil / Cyclotron resonance / Empirical models / Environmental health / Environmental impact / Environmental Pollution / Fourier transforms / Geochemistry / Hydrocarbons / Hydrophobicity / Ions / Marine environment / Marine organisms / Mass spectrometry / Mass spectroscopy / Methods / Oil spills / Organic chemicals / Petroleum / Petroleum - adverse effects / Petroleum - analysis / Polarity / Polycyclic aromatic hydrocarbons / Public health / Scientific imaging / Seawater / Seawater - analysis / Solubility / Spectroscopy, Fourier Transform Infrared / Studies / Toxicity / Toxicology / Water analysis / Water chemistry / Water Pollutants, Chemical - adverse effects / Water Pollutants, Chemical - analysis