A Tale of Two Recent Spills—Comparison of 2014 Galveston Bay and 2010 Deepwater Horizon Oil Spill Residues

Managing oil spill residues washing onto sandy beaches is a common worldwide environmental problem. In this study, we have analyzed the first-arrival oil spill residues collected from two Gulf of Mexico (GOM) beach systems following two recent oil spills: the 2014 Galveston Bay (GB) oil spill, and the 2010 Deepwater Horizon (DWH) oil spill. This is the first study to provide field observations and chemical characterization data for the 2014 GB oil spill. Here we compare the physical and chemical characteristics of GB oil spill samples with DWH oil spill samples and present their similarities and differences. Our field observations indicate that both oil spills had similar shoreline deposition patterns; however, their physical and chemical characteristics differed considerably. We highlight these differences, discuss their implications, and interpret GB data in light of lessons learned from previously published DWH oil spill studies. These analyses are further used to assess the long-term fate of GB oil spill residues and their potential environmental impacts.     

Adaptable mesocosm facility to study oil spill impacts on corals

Although numerous studies have been carried out on the impacts of oil spills on coral physiology, most have relied on laboratory assays. This scarcity is partly explained by the difficulty of reproducing realistic conditions in a laboratory setting or of performing experiments with toxic compounds in the field. Mesocosm systems provide the opportunity to carry out such studies with safe handling of contaminants while reproducing natural conditions required by living organisms. The mesocosm design is crucial and can lead to the development of innovative technologies to mitigate environmental impacts. Therefore, this study aimed to develop a mesocosm system for studies simulating oil spills with several key advantages, including true replication and the use of gravity to control flow‐through that reduces reliance on pumps that can clog thereby decreasing errors and costs. This adaptable system can be configured to (a) have continuous flow‐through; (b) operate as an open or closed system; (c) be fed by gravity; (d) have separate mesocosm sections that can be used for individual and simultaneous experiments; and (e) simulate the migration of oil from ocean oil spills to the nearby reefs. The mesocosm performance was assessed with two experiments using the hydrocoral Millepora alcicornis and different configurations to simulate two magnitudes of oil spills. With few exceptions, physical and chemical parameters remained stable within replicates and within treatments throughout the experiments. Physical and chemical parameters that expressed change during the experiment were still within the range of natural conditions observed in Brazilian marine environments. The photosynthetic potential (F_v/F_m) of the algae associated with M. alcicornis decreased in response to an 1% crude‐oil contamination, suggesting a successful delivery of the toxic contaminant to the targeted replicates. This mesocosm is customizable and adjustable for several types of experiments and proved to be effective for studies of oil spills.     

Oil pollution and climate have wide-scale impacts on seabird demographics

Oil spills often spell disaster for marine birds caught in slicks. However, the impact of oil pollution on seabird population parameters is poorly known because oil spills usually occur in wintering areas remote from breeding colonies where birds may be distributed over a wide area, and because it is difficult to separate the effects of oil pollution from the effect of natural environmental variation on seabird populations. Using a long-term data set we show that over-winter survival of adult common guillemots (Uria aalge) is negatively affected by both the incidence of four major oil-spills in their wintering grounds and high values of the North Atlantic Oscillation (NAO) index. After controlling for the effect of the NAO index, we show that winter mortality of adult guillemots is doubled by major oil pollution incidents. Our results demonstrate that oil pollution can have wide-scale impacts on marine ecosystems that can be quantified using populations of marked individuals to estimate survival.     

Amazon aquatic biodiversity imperiled by oil spills

Oil exploitation poses a significant threat to freshwater biodiversity, and future plans to develop petroleum leases in the Amazon Basin should be seem with caution. A series of oil spills have significantly affected biodiversity and human activities in some Amazonian basins, indicating that disturbances by petroleum activities will increase in the region, particularly in upper basins and river headwaters. Measures are needed to reduce the risk of spills and to minimize their impacts. More fundamentally, changes in decision making are needed that give proper weight to these impacts.     

Ecological response of nitrification to oil spills and its impact on the nitrogen cycle

Marine oil spills are catastrophic events that cause massive damage to ecosystems at all trophic levels. While most of the research has focused on carbon-degrading microorganisms, the potential impacts of hydrocarbons on microbes responsible for nitrification have received far less attention. Nitrifiers are sensitive to hydrocarbon toxicity: ammonia-oxidizing bacteria and archaea being 100 and 1000 times more sensitive than typical heterotrophs respectively. Field studies have demonstrated the response of nitrifiers to hydrocarbons is highly variable and the loss of nitrification activity in coastal ecosystems can be restored within 1–2 years, which is much shorter than the typical recovery time of whole ecosystems (e.g., up to 20 years). Since the denitrification process is mainly driven by heterotrophs, which are more resistant to hydrocarbon toxicity than nitrifiers, the inhibition of nitrification may slow down the nitrogen turnover and increase ammonia availability, which supports the growth of oil-degrading heterotrophs and possibly various phototrophs. A better understanding of the ecological response of nitrification is paramount in predicting impacts of oil spills on the nitrogen cycle under oil spill conditions, and in improving current bioremediation practices.     

Using multiple satellite observations to quantitatively assess and model oil pollution and predict risks and consequences to shoreline from oil platforms in the Caspian Sea

This research focused on the following objectives: (1) using satellite data to characterize the spatiotemporal distribution of anthropogenic oil spills from Oil Rocks Settlement, Chilov and Pirallahi Islands (2) stochastic modeling of the oil spill risk pose to water quality and shoreline ecosystems, and (3) validating model predictions using satellite images. 165 satellite images acquired by SENTINEL-1A, LANDSAT-8, RADARSAT, ENVISAT and ERS sensors between 1996 and 2015 were used for the detection of oil spills using object-based classification and visual interpretation. Anthropogenic hotspots were observed at three oldest oil production sites with estimated oil spilling up to 1264 m³ per day and different degrees of temporal repetition of oil spills. The largest area (5639 km²) experienced 1–10 detected oil spills, while 993 km² experienced 11–20 oil spills, 775 km² experienced 21–50 oil spills, 208 km² experienced 51–100 oil spills, and 36 km² experienced 101–150 oil spills. The majority (83% or 6157 km²) of sea surface area within the combined boundary of detected oil spills (7422 km²) had a 50% or greater chance of oil spill contamination. Approximately, 6% (44 km of 751 km) of shoreline had a 50% or greater probability of contamination with land use classes sensitive to pollution.     

Oil Spill Response Risk Judgments,Decisions, and Mental Models: Findings from Surveying U.S. Stakeholders and Coastal Residents

This study applies a mental models survey approach to assess public thinking about oil spills and oil spill response. Based on prior interdisciplinary oil spill response research, the study first applies qualitative interview results and a response risk decision model to the design of a survey instrument. The decision model considers controlled burning, public health, and seafood safety. Surveying U.S. coastal residents (36,978 pairs of responses) through Google Insights identifies beliefs and gaps in understanding as well as related values and preferences about oil spills, and oil spill responses. A majority of respondents are concerned about economic impacts of major oil spills, and tend to see ocean ecosystems as fragile. They tend to see information about chemical dispersants as more important than ecological baseline information, and dispersants as toxic, persistent, and less effective than other response options. Although respondents regard laboratory studies as predictive of the effects of oil and of controlled burning, they are less confident that scientists agree on the toxicity and effectiveness of dispersants. The results illustrate opportunities to reframe discussions of oil spill response in terms of tradeoffs between response options, and new possibilities for assessing public opinions and beliefs during events.     

Health status of Pomatoschistus microps populations in relation to pollution and natural stressors: implications for ecological risk assessment

Effects induced on wild populations by recurrent environmental contamination may difficult the ecological risk assessment of punctual pollution events such as oil spills. Here, the issue was addressed by comparing the health status of Pomatoschistus microps populations from four NW Iberian estuaries, using an integrated chemical-biological monitoring. Despite high seasonal variability, the parameters measured discriminated estuaries with different contamination levels and associated biological effects with chemical and abiotic stress. The decreased health status of fish from polluted sites strengthens the need of considering pollution-induced background effects and seasonal variability when assessing impacts and risks of oil and other chemical spills.     

STRANgE,integrated physical–biological–mechanical system for recovery in of the “oil spill” in Antarctic environment

Throughout the last century the increasing human activities in Antarctic region, particularly research expeditions, fishing, and tourism amplified the risk of oils spills at these high latitudes of the meridional hemisphere. A number of studies have been focused on chronic hydrocarbon contamination near Antarctic research stations revealing the presence and persistence of these human-derived contaminants. Marine ship-source oil spills in Antarctic region can have significant impacts on the marine environment. The key factors to effectively fight oil spills are a careful selection and proper use of the equipment and materials best suited to the critical local conditions. Despite the significant advances in the field of environmental recovery after an “oil spill” episode, research has recently shown that the usual techniques are often less effective than expected. This issue become much more relevant in the Antarctic case, not only for the incomparable environmental value of the Antarctic region but also for the extreme environmental conditions and the great distances from properly equipped centers, that make unfeasible sending naval vessels. Scope of the STRANgE Project is the preliminary design of a prototype floating platform, parachutable by plane, able to intervene as quickly as possible for the containment, removal and treatment/storage of the oil slick. New sorbent nanostructured materials and specialized Antarctic bacteria applications constitute the main innovations of this Project.     

Methodology for environmental assessments of oil and hazardous substance spills

Scientific assessment of the complex environmental consequences of large spills of oil or other hazardous substances has stimulated development of improved strategies for rapid and valid collection and processing of ecological data. The combination of coastal processes and geological measurements developed by Hayes & Gundlach (1978), together with selected field biological and chemical observations/measurements, provide an ecosystem impact assessment approach which is termed “integrated zonal method of ecological impact assessment.” Ecological assessment of oil and hazardous material spills has been divided into three distinct phases: (1) first-order response studies — conducted at the time of the initial spill event, which gather data to document acute impacts and assist decision-makers in prioritization of cleanup efforts and protection of ecologically sensitive habitats, (2) second-order response studies — conducted two months to one year post-spill, which document any delayed mortality and attempt to identify potential sublethal impacts in sensitive species, and (3) third-order response studies — conducted one to three years post-spill, to document chronic impacts (both lethal and sublethal) to specific indicator species. Data collected during first-order response studies are gathered in a quantitative manner so that the initial assessment may become a baseline for later, more detailed, post-spill scientific efforts. First- and second-order response studies of the “Peck Slip” oil spill in Puerto Rico illustrate the usefulness of this method. The need for contingency planning before a spill has been discussed along with the use of the Vulnerability Index, a method in which coastal environments are classified on a scale of 1–10, based upon their potential susceptibility to oiling. A study of the lower Cook Inlet section of the Alaskan coast illustrates the practical application of this method. Contribution 402, Gulf Breeze Environmental Research Laboratory     

Health status of Pomatoschistus microps populations in relation to pollution and natural stressors: implications for ecological risk assessment

Effects induced on wild populations by recurrent environmental contamination may difficult the ecological risk assessment of punctual pollution events such as oil spills. Here, the issue was addressed by comparing the health status of Pomatoschistus microps populations from four NW Iberian estuaries, using an integrated chemical–biological monitoring. Despite high seasonal variability, the parameters measured discriminated estuaries with different contamination levels and associated biological effects with chemical and abiotic stress. The decreased health status of fish from polluted sites strengthens the need of considering pollution-induced background effects and seasonal variability when assessing impacts and risks of oil and other chemical spills.     

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

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.     

A Method for Assessing Environmental Risks of Oil-Mineral-Aggregate to Benthic Organisms

Previous studies have shown that Oil-Mineral-Aggregate (OMA) formation enhances the dispersion of marine oil spills, but the potential impacts of settled OMAs on benthic organisms are not well known. A comprehensive numerical approach is proposed here to model the transport of OMAs and assesses their potential risks. The predicted environmental concentrations (PEC) of settled oil in OMAs was calculated using a random walk particle tracking model and the benchmark concentrations (BCs) of individual hydrocarbon groups were computed based on a equilibrium partitioning (EqP) approach. The likely of risks in terms of Hazard Quotient (HQ) were then determined using a Monte Carlo simulation method. HQ for both aliphatic and aromatic hydrocarbon groups were calculated for OMAs formed with two sediments, Mississippi River Delta (MRD) and Standard Reference Material (SRM). Mean total HQs were also determined by a simple sum of individual HQ. The predicted results from a case study based on a spill of 1000 tons of South Louisiana crude oil in the Gulf of St. Lawrence with a water depth of 80 m show that the SRM is unlikely to cause adverse impacts but this may not be the case for MRD. Furthermore, it has been found that the application of chemical dispersant (CD) increased the risks of MRD but it had little effects on SRM.     

Oil Impacts on Marine Invertebrate Populations and Communities

It is likely that roughly one billion gallons of oil entersour oceans each year as a result of man's activities. Only 8%of this input is believed to derive from natural sources. Atleast 22% is intentionally released as a function of normaltanker "operational discharges," 12% enters from accidentaltanker spills and another 36% from runoff and municipal andindustrial wastes. Invertebrate populations and communities form the foundationfor marine ecosystems and are continually subjected to stressesfrom both chronic and acute oil toxicity. The diversity of invertebratetaxa represented in the marine environment exhibit a wide rangeof responses to oil. Mortality is an obvious impact resultingfrom catastrophic spills or even chronic toxicity. Sublethalimpacts on individuals are manifested by physiological, carcinogenicand cytogenetic effects. Impacts typically felt at the populationlevel involve changes in abundance, age structure, populationgenetic structure, reproduction and reduced recruitment potential.Community level impacts are typified by modified interactionsbetween competitors, predator/prey and symbionts. Most importantly,changes in community structure represented by altered trophicinteractions tend to produce the most dramatic alterations tonatural invertebrate assemblages. Invertebrate communities respond to severe chronic oil pollutionand/or acute catastrophic oil pollution in much the same way.Initial massive mortality and lowered community diversity isfollowed by extreme fluctuations in populationsof opportunisticmobile and sessile fauna (and flora). Oscillations in populationnumbers slowly dampen over time and diversity slowly increasesto original levels. The time over which these events occur dependson the type of oil, the extent of the initial contamination,habitat type, weather conditions, latitude, the species assemblagesrepresented and a myriad of other complex factors.     

Mobility and Persistence of Petroleum Hydrocarbons in Peat Soils of Southeastern Mexico

Spilled crude petroleum from oil wells contains numerous hydrocarbons, some of which are toxic and threaten life. We have studied the mobility and persistence of hydrocarbons in waterlogged soils that contain large proportions of fermented organic matter (Histosols) and large concentrations of dissolved organic carbon (DOC) in the State of Tabasco, Mexico. We sampled soil and phreatic water at sites polluted by oil spills for several decades, as well as at sites that had only recently (few weeks) been polluted, and compared their hydrocarbon contents with those of unaffected sites in the same area. Samples were analyzed for 16 non-alkylated polyaromatic hydrocarbons (PAHs) and n-alkanes from nC9 to nC34. The spilled hydrocarbons had remained predominantly in the organic surface horizons of the soil where spillage occurred; there was little evidence of movement within the soil. The fraction of low molecular weight compounds was larger at sites of recent spills than where spills happened several decades ago. Nevertheless, sites of old spills still contained large concentrations of hydrocarbons, among which those of low molecular weight represented from 30 to 49% of total PAHs and from 50 to 84% of total n-alkanes, indicating that volatilization or microbial degradation is slow in these soils. In the peat horizons the measured organic carbon partition coefficients (K _oc ) for the higher molecular weight PAHs were consistently smaller than those estimated by empirical equations by up to two orders of magnitude. The dissolved organic carbon of these peat soils seems to influence this behavior. At sites of old spills, partition coefficients for the PAHs were larger than at sites of recent spills.     

Microbial gene functions enriched in the Deepwater Horizon deep-sea oil plume

The Deepwater Horizon oil spill in the Gulf of Mexico is the deepest and largest offshore spill in the United State history and its impacts on marine ecosystems are largely unknown. Here, we showed that the microbial community functional composition and structure were dramatically altered in a deep-sea oil plume resulting from the spill. A variety of metabolic genes involved in both aerobic and anaerobic hydrocarbon degradation were highly enriched in the plume compared with outside the plume, indicating a great potential for intrinsic bioremediation or natural attenuation in the deep sea. Various other microbial functional genes that are relevant to carbon, nitrogen, phosphorus, sulfur and iron cycling, metal resistance and bacteriophage replication were also enriched in the plume. Together, these results suggest that the indigenous marine microbial communities could have a significant role in biodegradation of oil spills in deep-sea environments.     

Recruitment and survival of immature seabirds in relation to oil spills and climate variability

1. In long-lived animals with delayed maturity, the non-breeding component of the population may play an important role in buffering the effects of stochastic mortality. Populations of colonial seabirds often consist of more than 50% non-breeders, yet because they spend much of their early life at sea, we understand little about their impact on the demographic process. 2. Using multistate capture-mark-recapture techniques, we analyse a long-term data set of individually identifiable common guillemots, Uria aalge Pont., to assess factors influencing their immature survival and two-stage recruitment process. 3. Analysis of the distribution of ringed common guillemots during the non-breeding season, separated by age classes, revealed that all age classes were potentially at risk from four major oil spills. However, the youngest age class (0-3 years) were far more widely spread than birds 4-6 years old, which were more widely spread than birds aged 6 and over. Therefore the chance of encountering an oil spill was age-dependent. 4. A 2-year compound survival estimate for juvenile guillemots was weakly negatively correlated with winter sea-surface temperature, but was not influenced by oil spills. Non-breeder survival did not vary significantly over time. 5. In years following four oil spills, juvenile recruitment was almost double the value in non-oil-spill years. Recent work from Skomer Island showed a doubling of adult mortality associated with major oil spills, which probably reduced competition at the breeding colony, allowing increased immature recruitment to compensate for these losses. We discuss the implications of compensatory recruitment for assessing the impact of oil pollution incidents.     

Oil spill remediation by using the remediation agent JE1058BS that contains a biosurfactant produced by Gordonia sp. strain JE-1058

A remediation agent containing a biosurfactant was prepared by spray drying the sterilized culture broth of Gordonia sp. strain JE-1058, and the agent was designated as JE1058BS. On subjection to the baffled flask test developed by the United States Environmental Protection Agency, JE1058BS showed a strong potential to be applied as an oil spill dispersant even in the absence of a solvent. It also proved to be an effective bioremediation agent for the remediation of oil spills at sea. The addition of JE1058BS to seawater stimulated the degradation of weathered crude oil (ANS 521) via the activity of the indigenous marine bacteria. Its addition also stimulated the removal of crude oil from the surface of contaminated sea sand. These results indicate that biosurfactant-containing JE1058BS has a strong potential to be applied as a remediation agent for the clean-up of oil spills at sea and on shorelines.     

Oil and Gas Wells and Pipelines on U.S. Wildlife Refuges: Challenges for Managers

The increased demand for oil and gas places a burden on lands set aside for natural resource conservation. Oil and gas development alters the environment locally and on a much broader spatial scale depending on the intensity and extent of mineral resource extraction. The current increase in oil and gas exploration and production in the United States prompted an update of the number of pipelines and wells associated with oil and gas production on National Wildlife Refuge System (NWRS) lands. We obtained geospatial data on the location of oil and gas wells and pipelines within and close to the boundaries of NWRS lands (units) acquired as fee simple (i.e. absolute title to the surface land) by the U.S. Fish and Wildlife Service. We found that 5,002 wells are located in 107 NWRS units and 595 pipelines transect 149 of the 599 NWRS units. Almost half of the wells (2,196) were inactive, one-third (1,665) were active, and the remainder of the wells were either plugged and abandoned or the status was unknown. Pipelines crossed a total of 2,155 kilometers (1,339 miles) of NWRS fee simple lands. The high level of oil and gas activity warrants follow up assessments for wells lacking information on production type or well status with emphasis on verifying the well status and identifying abandoned and unplugged wells. NWRS fee simple lands should also be assessed for impacts from brine, oil and other hydrocarbon spills, as well as habitat alteration associated with oil and gas, including the identification of abandoned oil and gas facilities requiring equipment removal and site restoration.     

Demographic trends of Brown Pelicans in Louisiana before and after the Deepwater Horizon oil spill

Marine oil spills may have extensive and deleterious effects on coastal waterbirds, but pre‐spill data sets are often not available for making comparisons of demographics to the period following a spill. The 2010 Deepwater Horizon oil spill allowed us to compare Brown Pelican (Pelecanus occidentalis) demographics during pre‐ and post‐spill years. We banded 1114 pelicans on Louisiana barrier islands from 2007 to 2009, tracked their distribution via band re‐sighting surveys from 2008 to 2011, and conducted age‐structure surveys. Across Louisiana coastal islands in 2011, we detected 7% of pelicans that had been oiled during the 2010 spill and released following rehabilitation. Similarly, 6% of pelicans (not oiled) banded at the same release site in 2007 were observed across coastal islands 1 yr after banding. We observed variation in proportions of pelicans that were 1, 2, and 3 or more years old among years (2008–2011) and across islands, but little variation could readily be assigned to spill‐related mortality. These Brown Pelican demographic trends one year following the Deepwater Horizon oil spill are contrary to other assessments of the impacts of oil contamination on marine birds. However, additional research is required to evaluate potential long‐term population trends.