The weathering of oil after the Deepwater Horizon oil spill: insights from the chemical composition of the oil from the sea surface, salt marshes and sediments

Abstract

The oil released during the Deepwater

Persistence and biodegradation of oil at the ocean floor following Deepwater Horizon

“…These droplets remained concentrated close to the well's coordinates (2,11,12,15), but modeling suggests that droplet size drove further vertical partitioning, with droplets >50 μm mixing upwards by August 2010 and smaller droplets remaining suspended in the deep ocean (7,17,18). Some suspended oil was eventually deposited to the seafloor, likely via oilmineral aggregates or microbial flocs (8,19,20), with intense contamination within ∼5 km of the well (21)(22)(23)(24)(25)(26). Surficial sediments near the well were found to carry >1,000-fold-elevated concentrations of dioctyl sodium sulfosuccinate (4), an active ingredient of the chemical dispersant applied at the wellhead, and to exhibit a radiocarbon deficit consistent with oil deposition (27).…”

Deepwater Horizon Oil Spill as a Case Study for Interdisciplinary Cooperation within Developmental Biology, Environmental Sciences and Physiology

“…The oil from the DHOS is a light crude oil containing a high percentage of low molecular weight polycyclic aromatic hydrocarbons (PAHs) [6]. Polycyclic aromatic hydrocarbons are toxicants derived from crude oil, incomplete combustion of fossil fuels and other anthropogenic sources.…”

“…wave action), microbial degredation, pressure, photooxidation, and temperature are among factors that can change the composition of oil over time [6] [11] [12]. This differential loss of various chemicals from crude oil is called "weathering", and results in varied composition of toxicants in DHOS crude oil dependent on the degree and duration of environmental exposure [6] [12]. Regardless of oil composition and weathering, PAHs are persistent, remaining in weathered oil and oil-laden sediments, potentially for decades [3] [13].…”

Going Beyond the Analysis of Common Contaminants: Target, Suspect, and Non-Target Analysis of Complex Environmental Matrices by High-Resolution Mass Spectrometry

“…On April 20, 2010, a turbulent mixture of gas and a light, sweet (Macondo type) crude oil was released into the Gulf of Mexico as a result of the Deepwater Horizon (DWH) drilling rig incident in the Mississippi Canyon Block 252 (MC252) Camilli et al, 2012;. In the days following the accident, some of the escaped Macondo oil rose 1500 m to the surface of the ocean, creating oil slicks some of which ultimately reached the coast (Liu et al, 2012). In the event of crude oil discharges into marine environments, weathering processes such as dissolution, dispersion, emulsification, evaporation, biodegradation, and photo-oxidation Wang et al, 2013) constantly modify the oil composition (Jordan and Payne, 1980;Wang et al, 2013).…”

“…Unsurprisingly, reports have shown that, with increased weathering, the oil was depleted of most of its saturated and aromatic compounds Atlas and Hazen, 2011;Kostka et al, 2011;Lima et al, 2005;Liu et al, 2012). However, estimated that in surface slicks only about 40% of the total mass of hydrocarbons could be analyzed by conventional GC-based techniques, while Reddy et al (2012) estimated that for weathered Macondo oil traditional analytes only account for less than 25% of the oil mass.…”