Crude Oil Spill Exposure and Human Health Risks

Fabrication of Triblock Elastomer Foams and Gelation Studies for Oil Spill Remediation

Polymeric foamed materials are among the most widely utilized technologies for oil spill accidents and releases of oil-contaminated wastewater oil due to their porosity to absorb and separate oil/water effectively. However, a major limitation of traditional polymeric foams is their reliance on an ad/absorption mechanism as the sole method of oil capture, leading to potential oil leakage once their saturation point is exceeded. Tri-block polymer styrene-ethylene-butylene-styrene (SEBS) is a fascinating absorbent material that can bypass this limitation by both capturing oil and providing a sealing mechanism via gelation to prevent oil leakage due to its unique chemical structure. SEBS foams are produced via simultaneous crosslinking and foaming that results in an impressive expansion ratio of up to 15.2 with over 93% porosity. Most importantly, the SEBS foams show great potential as oil absorbents in spill remediation, demonstrating rapid and efficient oil absorption coupled with superhydrophobic properties. Moreover, the unique interaction between the oil and SEBS enables the formation of a physical gel, acting as an effective barrier against oil leakage. These findings indicate the potential for commercializing SEBS foam as a viable option for geotextiles to mitigate oil spill concerns from infrastructures.

Toxicological Effects of Inhaled Crude Oil Vapor

PURPOSE OF REVIEW

The purpose of this review is to assess the toxicological consequences of crude oil vapor (COV) exposure in the workplace through evaluation of the most current epidemiologic and laboratory-based studies in the literature.

RECENT FINDINGS

Crude oil is a naturally occuring mixture of hydrocarbon deposits, inorganic and organic chemical compounds. Workers engaged in upstream processes of oil extraction are exposed to a number of risks and hazards, including getting crude oil on their skin or inhaling crude oil vapor. There have been several reports of workers who died as a result of inhalation of high levels of COV released upon opening thief hatches atop oil storage tanks. Although many investigations into the toxicity of specific hydrocarbons following inhalation during downstream oil processing have been conducted, there is a paucity of information on the potential toxicity of COV exposure itself. This review assesses current knowledge of the toxicological consequences of exposures to COV in the workplace.

Role of Candida in the bioremediation of pollutants: a review

The population and modernization of society have increased dramatically from past few decades. In order to meet societal expectations, there has been a massive industrialization and resource exploitation. Anthropogenic practices like disposal of hazardous waste, large carbon footprint release variety of xenobiotic substances into the environment, which endanger the health of the natural ecosystem. Therefore, discovering proper long-term treatment approaches is a global concern. Various physical and chemical approaches are employed to remove contaminants. However, these technologies possess limitations like high cost and low efficacy. Consequently, bioremediation is regarded as one of the most promising remedies to these problems. It creates the option of either totally removing pollutants or transforming them into nonhazardous compounds with the use of natural biological agents. Several microorganisms are being utilized for bioremediation among which yeasts possess benefits such as high biodegradability, ease of cultivation etc. The yeast of Candida genus has the capability to effectively eliminate heavy metal ions, as well as to degrade and emulsify hydrocarbons which makes it a promising candidate for this purpose. The review highlights many potential uses of Candida in various remediation strategies and discusses future directions for research in this field.

Sorption Capacity of Polydimethylsiloxane Foams Filled with Thermal-Treated Bentonite-Polydimethylsiloxane Composite Foams for Oil Spill Remediation

The spillage of oil causes severe and long-lasting impacts on both the environment and human life. It is crucial to carefully reconsider the methods and techniques currently employed to recover spilled oil in order to prevent any possible secondary pollution and save time. Therefore, the techniques used to recover spilled oil should be readily available, highly responsive, cost-effective, environmentally safe, and, last but not least, they should have a high sorption capacity. The use of sorbents obtained from natural materials is considered a suitable approach for dealing with oil spills because of their exceptional physical characteristics that support sustainable environmental protection strategies. This article presents a novel sorbent material, which is a composite siloxane foam filled with bentonite clay, aimed at enhancing the hydrophobic and oleophilic behavior of the material. The thermal treatment of bentonite optimizes its sorption capacity by eliminating water, and increasing the surface area, and, consequently, its interaction with oils. In particular, the maximum sorption capacity is observed in kerosene and naphtha for the bentonite clay thermally treated at 600 °C, showing an uptake at saturation of 496.8% and 520.1%, respectively. Additionally, the reusability of the composite foam is evaluated by squeezing it after reaching its saturation point to determine its sorption capacity and reusability.

Biological effects of inhaled crude oil vapor. III. Pulmonary inflammation, cytotoxicity, and gene expression profile

OBJECTIVE

Workers may be exposed to vapors emitted from crude oil in upstream operations in the oil and gas industry. Although the toxicity of crude oil constituents has been studied, there are very few in vivo investigations designed to mimic crude oil vapor (COV) exposures that occur in these operations. The goal of the current investigation was to examine lung injury, inflammation, oxidant generation, and effects on the lung global gene expression profile following a whole-body acute or sub-chronic inhalation exposure to COV.

MATERIALS AND METHODS

To conduct this investigation, rats were subjected to either a whole-body acute (6 hr) or a sub-chronic (28 d) inhalation exposure (6 hr/d × 4 d/wk × 4 wk) to COV (300 ppm; Macondo well surrogate oil). Control rats were exposed to filtered air. One and 28 d after acute exposure, and 1, 28, and 90 d following sub-chronic exposure, bronchoalveolar lavage was performed on the left lung to collect cells and fluid for analyses, the apical right lobe was preserved for histopathology, and the right cardiac and diaphragmatic lobes were processed for gene expression analyses.

RESULTS

No exposure-related changes were identified in histopathology, cytotoxicity, or lavage cell profiles. Changes in lavage fluid cytokines indicative of inflammation, immune function, and endothelial function after sub-chronic exposure were limited and varied over time. Minimal gene expression changes were detected only at the 28 d post-exposure time interval in both the exposure groups.

CONCLUSION

Taken together, the results from this exposure paradigm, including concentration, duration, and exposure chamber parameters, did not indicate significant and toxicologically relevant changes in markers of injury, oxidant generation, inflammation, and gene expression profile in the lung.

Exposure to Crude Oil-Related Volatile Organic Compounds Associated with Lung Function Decline in a Longitudinal Panel of Children

BACKGROUND

Children in the affected area were exposed to large amounts of volatile organic compounds (VOCs) from the Hebei Spirit oil spill accident.

OBJECTIVES

We investigated the lung function loss from the exposure to VOCs in a longitudinal panel of 224 children 1, 3, and 5 years after the VOC exposure event.

METHODS

Atmospheric estimated concentration of total VOCs (TVOCs), benzene, toluene, ethylbenzene, and xylene for 4 days immediately after the accident were calculated for each village (n = 83) using a modeling technique. Forced expiratory volume in 1 s (FEV₁) as an indicator of airway status was measured 1, 3, and 5 years after the exposure in 224 children 4~9 years of age at the exposure to the oil spill. Multiple linear regression and linear mixed models were used to evaluate the associations, with adjustment for smoking and second-hand smoke at home.

RESULTS

Among the TVOCs (geometric mean: 1319.5 mg/m³·4 d), xylene (9.4), toluene (8.5), ethylbenzene (5.2), and benzene (2.0) were dominant in the order of air concentration level. In 224 children, percent predicted FEV₁ (ppFEV₁), adjusted for smoking and second-hand smoke at home, was 100.7% after 1 year, 96.2% after 3 years, and 94.6% after 5 years, and the loss over the period was significant (p < 0.0001). After 1 and 3 years, TVOCs, xylene, toluene, and ethylbenzene were significantly associated with ppFEV₁. After 5 years, the associations were not significant. Throughout the 5 years' repeated measurements in the panel, TVOCs, xylene, toluene, and ethylbenzene were significantly associated with ppFEV₁.

CONCLUSIONS

Exposure to VOCs from the oil spill resulted in lung function loss among children, which remained significant up to 5 years after the exposure.

Evolution of polycyclic aromatic hydrocarbons in the surface sediment of southern Jiaozhou Bay in northern China after an accident of oil pipeline explosion

The 2013 "Qingdao oil pipeline explosion" contaminated about 2.5 km of shoreline in the Jiaozhou Bay area and aroused widespread concern because of the serious casualties even though it was not the most severe oil-spill contamination in China. To evaluate the long-term impact, we collected thirty-three surface sediment samples after 3 years of the accident, with sixteen polycyclic aromatic hydrocarbons (PAHs) detected. Spatial-temporal variation in PAHs revealed that a minimal impact might still be present after 3 years. Source analysis combined with a one-way ANOVA showed that pyrolytic sources were consistently predominant. The environmental impact was already minimal 3 years later and negligible thereafter. Although the cancer risk has decreased over the years, there has always been a potential hazard to human for specific occupation, with all of the risk values exceeded 10^-6. This study offers a reference for assessing the long-term impact of oil spills in similar bay areas.

Biological effects of crude oil vapor. IV. Cardiovascular effects

Workers in the oil and gas extraction industry are at risk of inhaling volatile organic compounds. Epidemiological studies suggest oil vapor inhalation may affect cardiovascular health. Thus, in this hazard identification study we investigated the effects of inhalation of crude oil vapor (COV) on cardiovascular function. Male rats were exposed to air or COV (300 ppm) for 6 h (acute), or 6 h/day × 4 d/wk. × 4 wk. (sub-chronic). The effects of COV inhalation were assessed 1, 28, and 90 d post-exposure. Acute exposure to COV resulted in reductions in mean arterial and diastolic blood pressures 1 and 28 d after exposure, changes in nitrate-nitrite and H₂O₂ levels, and in the expression of transcripts and proteins that regulate inflammation, vascular remodeling, and the synthesis of nitric oxide (NO) in the heart and kidneys. The sub-chronic exposure resulted in a reduced sensitivity to α₁-adrenoreceptor-mediated vasoconstriction in vitro 28 d post-exposure, and a reduction in oxidative stress in the heart. Sub-chronic COV exposure led to alterations in the expression of NO synthases and anti-oxidant enzymes, which regulate inflammation and oxidative stress in the heart and kidneys. There seems to be a balance between changes in the expression of transcripts associated with the generation of reactive oxygen species (ROS) and antioxidant enzymes. The ability of antioxidant enzymes to reduce or inhibit the effects of ROS may allow the cardiovascular system to adapt to acute COV exposures. However, sub-chronic exposures may result in longer-lasting negative health consequences on the cardiovascular system.

Socio-environmental disasters and their impacts: socioeconomic consequences of the oil spill in the northeast region of Brazil

The 2019 oil spill was the biggest in Brazilian history. Oil was found along more than 3,000 km of the Brazilian coastline, mainly in the Northeast, in more than 1,000 localities. This article analyzes the disaster's damage using a sample of interviewers who were impacted - fishers, tourism and beach hawkers - distributed along 40 of the affected municipalities in the Northeast Region of Brazil. The socio-economic indicators obtained by the research show that the impacts were not homogeneous between the segments and cities researched. Localities specialized in tourism and with a workforce relatively more specialized in fishing were the most affected. Accordingly, the populations of fishers and beach hawkers suffered the most severe impacts in terms of income reduction and the sale of products. These agents report a negative impact of the disaster on their work activities of 73% (fishers) and 65% (beach vendors), while the lodging and food sectors reported losses in about 38% of the cases. The interviewees' health indicators demonstrated that the volunteers at the oil spill clean- up suffered damage due to the exposure experienced, evidencing the public health emergency dimension of the disaster.

Low-temperature carbonization synthesis of carbon-based super-hydrophobic foam for efficient multi-state oil/water separation

In view of the complexity and diversity of multi-state oils, the development of green and low-cost materials with high selectivity to oils has important ecological significance in the polluted water treatment. Herein, a simple method was proposed to develop large-scale production of superhydrophobic sponges (CPMF200 sponges) for high-efficiency oil/water separation under different complex environments. The as-prepared CPMF200 sponges possessed many superior properties, including high roughness, well-developed porosity, good thermal stability, excellent chemical stability, and superhydrophobic properties (water contact angle is 152°), which is conducive to high oil adsorption capacity (up to 70-179 times of its own weight) and oil-water separation. More importantly, the CPMF400 sponge has an excellent photothermal conversion capability to improve the fluidity of high viscosity oil for oil recovery. Based on a simple synthesis method, it exhibits high-efficiency absorption of multi-state oils and excellent oil-water separation performance and strongly proves their application prospects in treating oily wastewater.

Modelling of self-sustainable microbial fuel cell type oil sensors based on restricted oxygen transfer and two-population competition

Oil leaks during oil industrial chain pose threats to the ecosystem. The microbial fuel cell-type oil sensor has been developed for early warning of such issues. Oil contacting with the sensor restricts oxygen availability and triggers correlative signal anomaly which serves as indicative of the oil presence. To extend its application for the real world, modelling of the sensor is required to pre-describe the signal behavior under unknown conditions. Therefore, by integrating Butler-Volmer, restricted oxygen transfer (ROT) and Monod equations, a dynamic ROT-MFC model with sufficient substrate precondition was developed. The ROT-MFC model was trained on the experimental single-oil-shock test (R 2 = 0.996) and validated by the experimental sequential-shocktest (R 2 = 0.998). Numerical analysis of the trained ROT-MFC model indicates that the single-shock detection has higher sensitivity (≥40.6 mV/detection) and the sequential-shocks detection spends a shorter response time (≤2.2 h). Besides, the sequential-shocks detection with proper strategy is more applicable due to flexible options on detection limit and working range. The model was further evolved into the TPC-ROT-MFC model by introducing a two-population competition (TPC) theory to describe performance under limited substrate conditions. Results indicate a critical substrate concentration range (42.1 to 62.8 mg-COD/L) for dividing baseline steadiness, and that the impact of substrate concentration on anodic charge transfer coefficient soars when the substrate concentration lessens furtherly. This sensor model is relatively easy to implement and may enhance practical use for design and operation.

Oil Palm’s Empty Fruit Bunch as a Sorbent Material in Filter System for Oil-Spill Clean Up

Oil pollution such as diesel poses a significant threat to the environment. Due to this, there is increasing interest in using natural materials mainly from agricultural waste as organic oil spill sorbents. Oil palm’s empty fruit bunch (EFB), a cost-effective material, non-toxic, renewable resource, and abundantly available in Malaysia, contains cellulosic materials that have been proven to show a good result in pollution treatment. This study evaluated the optimum screening part of EFB that efficiently absorbs oil and the physicochemical characterisation of untreated and treated EFB fibre using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The treatment conditions were optimised using one-factor-at-a-time (OFAT), which identified optimal treatment conditions of 170 °C, 20 min, 0.1 g/cm³, and 10% diesel, resulting in 23 mL of oil absorbed. The predicted model was highly significant in statistical Response Surface Methodology (RSM) and confirmed that all the parameters (temperature, time, packing density, and diesel concentration) significantly influenced the oil absorbed. The predicted values in RSM were 175 °C, 22.5 min, 0.095 g/cm³, and 10%, which resulted in 24 mL of oil absorbed. Using the experimental values generated by RSM, 175 °C, 22.5 min, 0.095 g/cm³, and 10%, the highest oil absorption achieved was 24.33 mL. This study provides further evidence, as the data suggested that RSM provided a better approach to obtain a high efficiency of oil absorbed.

Environmental implications of petroleum spillages in the Niger Delta region of Nigeria: A review

The issue of environmental pollution has been recognized as a typical example of an anthropogenic activity that constitutes a global challenge coupled with the influence of climate change. This has constituted several hazards which include bioaccumulation of toxic substances, pollution of the aquatic environment, and high rate of dilapidation of soil structure and texture, health hazards, high level of imbalance in the ecosystem and a high level of toxicity in humans and the environment. Despite the intervention of governments, industries, researchers and relevant stakeholders, these problems remain paramount in most regions. Therefore, given the aforementioned, it is essential to identify sustainable remediation techniques, innovative knowledge on remediation strategies and clean up techniques that could help in the mitigation of all these highlighted challenges. Moreover, several studies have revealed the deleterious influence of petroleum or oil spillages resulting in irreparable environmental dilapidation and other potential hazards to human health, agriculture, climate system, and the ecosystem in general. From the systematic analysis of the evidence-based, meta-data-based review and other reviewed literature, it is noticeable that there is scant holistic review study that will incorporate all these aforementioned environmental implications resulting from the activities of petroleum resources in the Niger Delta region of Nigeria (NDRN) in just a single study. In the interim, it is alleged that there is hardly a permanent and tangible solution to these petroleum spillage issues and their impacts on the region; albeit, awareness will be fundamental for its mitigation. Hence, this review study will attempt to fill this gap by holistically reviewing the selected environmental implications of petroleum spillages in the NDRN drawn from 219 evidence and meta-data-based reviews and other articles. Furthermore, the relevant legal frameworks that could guild in protecting against environmental issues and petroleum spillages, are discussed in this study. In conclusion, the study cautiously provides a way forward by submitting that effective research and development measures ranging from public health assessments of petroleum contamination to an all-embracing application of bioremediation technology should frequently be carried out as a matter of urgency with resilient adaptation, mollification and management of these menaces.

What Helps Oiled Wildlife Responders Care for Animals While Minimizing Stress and Compassion Fatigue

Simple Summary

An oil spill can have severe environmental effects, as well as impacting the wellbeing of first responders. Oiled wildlife responders are a key professional group for the identification of wildlife at risk and to provide measures to rescue, rehabilitate and release wildlife back to their clean habitat. Currently, there is limited information documenting impacts to responders’ mental health during a spill response relating to stress, burnout and compassion fatigue; thus, there are limited interventions and strategies that can support responders and address these issues. A survey for oiled wildlife responders who participated in either the New Zealand MV Rena incident or the US Refugio pipeline oil spill was instigated to investigate and contribute to this knowledge gap. Results indicated that to support the health and wellbeing of oiled wildlife responders and sustain them to provide the best achievable care for oiled wildlife, ongoing professional training supported by organizations and professional networks in the areas of emergency preparedness, resilience, self-care and capacity building should be made available to enhance compassion satisfaction and role fulfilment.

Abstract

Oil spills are environmental disasters and their long-term impact is not just a concern for the environment and economy, but also for first responders’ health and wellbeing. Wildlife, such as aquatic birds and certain marine mammals, are highly susceptible to physiological effects of oiling, and oiled wildlife responders are crucial to provide measures for their survival. The purpose of this research was to explore the experiences of oiled wildlife responders and what factors and conditions have helped or inhibited the responders to care-affected wildlife. This study collected responses (n = 50) from a survey of responders who attended either the New Zealand MV Rena or US Refugio pipeline oil spills. Study participants were mostly older (>40), highly educated females. We found there were significant differences in compassion satisfaction, resilience, burnout and overall satisfaction based on age, gender and role. While most responders have only attended limited numbers of oil spill incidents, they reported positive experiences and found it rewarding. Findings from responders indicated that to lessen stress and compassion fatigue during an incident, provision of training and support from professional organizations equips responders with knowledge and skills that can support their personal resilience to respond to disaster events.

Sorbent-based devices for the removal of spilled oil from water: a review

Always, oil spills do cause serious and dire consequences for the environment, nature, and society that it consumes much time and socio-economic resources to overcome such consequences. Oil spills, hence, posed a big challenge in searching the advanced technologies and devices to recover spilled oil rapidly and efficiently. Indeed, sorbents have been found to play an extremely critical role in the spilled-oil remediation processes. Recently, a large number of various advanced sorbents and sorbent-based oil-collecting devices/technologies have been developed to enhance the oil-recovery capacity. Therefore, it is necessary to have a comprehensive assessment of the application of sorbent-based oil-collecting devices/technologies in recovering spilled oil. Due to this reason, this paper aims to provide a comprehensive review of the advanced technologies of the combination of sorbents and oil-collecting devices in the oil cleanup strategies. Two main oil-collecting devices such as booms and skimmers that could conjunct with sorbents were critically evaluated on the basis of the applicability and technological features, indicating that the capacity of oil spill recovery could achieve 90%. Moreover, oil-storage and oil-collecting devices were also completely mentioned. Last but not least, technical directions, concerns over the application of sorbents in oil recovery, and existing challenges relating to storage, transport, and disposal of used sorbents were discussed in detail. In the future, the automatic process of spilled oil recovery with the conjunction between advanced devices and environmentally friendly high-efficiency sorbents should be further investigated to minimize the environmental impacts, reduce the cost, as well as maximize the collected oil spill.

Polycyclic aromatic hydrocarbons (PAHs) cycling and fates in Galveston Bay, Texas, USA

The cycling and fate of polycyclic aromatic hydrocarbons (PAHs) is not well understood in estuarine systems. It is critical now more than ever given the increased ecosystem pressures on these critical coastal habitats. A budget of PAHs and cycling has been created for Galveston Bay (Texas) in the northwestern Gulf of Mexico, an estuary surrounded by 30-50% of the US capacity of oil refineries and chemical industry. We estimate that approximately 3 to 4 mt per year of pyrogenic PAHs are introduced to Galveston Bay via gaseous exchange from the atmosphere (ca. 2 mt/year) in addition to numerous spills of petrogenic PAHs from oil and gas operations (ca. 1.0 to 1.9 mt/year). PAHs are cycled through and stored in the biota, and ca. 20 to 30% of the total (0.8 to 1.5 mt per year) are estimated to be buried in the sediments. Oysters concentrate PAHs to levels above their surroundings (water and sediments) and contain substantially greater concentrations than other fish catch (shrimp, blue crabs and fin fish). Smaller organisms (infaunal invertebrates, phytoplankton and zooplankton) might also retain a significant fraction of the total, but direct evidence for this is lacking. The amount of PAHs delivered to humans in seafood, based on reported landings, is trivially small compared to the total inputs, sediment accumulation and other possible fates (metabolic remineralization, export in tides, etc.), which remain poorly known. The generally higher concentrations in biota from Galveston Bay compared to other coastal habitats can be attributed to both intermittent spills of gas and oil and the bay's close proximity to high production of pyrogenic PAHs within the urban industrial complex of the city of Houston as well as periodic flood events that transport PAHs from land surfaces to the Bay.

Novel Magnetic Nano Silica Synthesis Using Barley Husk Waste for Removing Petroleum from Polluted Water for Environmental Sustainability

Water contamination by petroleum and its byproducts presents a major challenge worldwide. It is critical that sustainable treatment methods be employed for the removal of such contaminants from polluted water. For this investigation, magnetic nano silica (M-NS) was synthesized using agricultural waste from barley husk using a two-step process that is environmentally friendly and uses green chemistry synthesis. The barley husk waste was used as a precursor for the synthesis of nano-silica following a low energy and sustainable method of acid reflux and heat treatment. Nano-silica was then used for the synthesis of M-NS, with the addition of a magnetic solution of Fe3O4 nanoparticles. The magnetic nano-silica particles were characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR), Zeta potential analysis (ZETA) and X-Ray Diffraction (XRD). Magnetic nano-silica particles were observed to have an average diameter of 162 nm and appeared to be hydrophobic, with a large surface area of ~120 m2/gm. Due to these characteristics, magnetic nano-silica was used as an adsorbent for the removal of petrol contaminants from water. The experimental procedure showed that only 0.6 gm. of M-NS was used on 40 mg/L concentration of petroleum and the experiments recorded a high uptake efficiency of 85%. The sorption was shown to be an effective process since a high amount of petroleum was removed. The study further demonstrates that as the amount of sorbent is increased, the sorption capacity also increases until an equilibrium is reached. The results of this study establish that synthesis of M-NS, using environmentally sustainable processes, has the required characteristics to serve as sorbent for petroleum and its byproducts from contaminated water, thus enhancing environmental sustainability.

Fatty acid metabolism and brain mitochondrial performance of juvenile Nile tilapia (Oreochromis niloticus) exposed to the water-accommodated fraction of Maya crude oil

Crude oil and its derivatives are still the primary source of energy for humankind. However, during its transportation and treatment, spills of this resource can occur in aquatic environments. Nile tilapia is one of the most globally widespread fish species. This species is even found in brackish water due to its tolerance to salinity and pollution. In this study, the performance of brain cells (mitochondrial membrane potential [ΔΨm], calcium [Ca²⁺] and O₂ and H₂O₂ levels) exposed to crude oil was assessed. In addition, fatty acid metabolism (cholesterol concentration and fatty acid synthase [FAS], acyl CoA-oxidase [AOX] and catalase [CAT] activities) in the brain, heart, liver and intestine of Nile tilapia exposed to the water-accommodated fraction (WAF) of 0.01, 0.1 or 1 g/L Maya crude oil (MCO) for 96 h were evaluated. After exposure, in brain cells, there were only increases in ROS and slight reductions in ΔΨm. Exposure to WAF of MCO induced and increased the levels of cholesterol and altered FAS and AOX activities in all examined tissues. The brain is the most susceptible organ to alterations in the activity of fatty acid metabolic enzymes and cholesterol levels relative to the heart, liver and intestine. The correlation between inhibition of the activity of CAT and AOX suggests a possible reduction in the proliferation and size of peroxisomes. Most biomarkers were significantly altered in the brains of Nile tilapia exposed to the WAF containing 1 g/L MCO in comparison to the control.

Effect of oil spills on infant mortality in Nigeria

Onshore oil spills can lead to irreversible environmental degradation and potentially pose hazards to human health, but scientific evidence on their health effects is lacking. We fill this gap by studying the causal effects of onshore oil spills on neonatal and infant mortality rates. We compare siblings conceived before and after nearby oil spills and find that nearby oil spills double the neonatal mortality rate. Given that oil spills occur with high frequency in the densely populated areas along pipelines in Nigeria, they are the cause of an alarming ongoing human tragedy. Our results suggest that efforts to prevent oil spills in the Niger Delta could save the lives of thousands of newborns every year.

Oil spills can lead to irreversible environmental degradation and are a potential hazard to human health. We study how onshore oil spills affect neonatal and infant mortality by combining spatial data from the Nigerian Oil Spill Monitor with Demographic and Health Surveys. To identify a causal effect, we compare siblings born to the same mother, conceived before and after a nearby oil spill. We find that nearby oil spills that occur before conception increase neonatal mortality by 38.3 deaths per 1,000 live births, which corresponds to an increase of around 100% on the sample mean. The effect is fairly uniform across girls and boys, socio-economic backgrounds, and locations. We show that this effect is not driven by events related to oil production or violent conflict. Rather, our results are consistent with medical and epidemiological evidence showing that exposure to hydrocarbons can pose risks to fetal development. We provide further evidence suggesting that the effects of oil spills on neonatal mortality persist for several years after the occurrence of an oil spill.

The Development of Long-Term Adverse Health Effects in Oil Spill Cleanup Workers of the Deepwater Horizon Offshore Drilling Rig Disaster

Background

The purpose of this study was to assess the long-term adverse health effects of the 2010 Deepwater Horizon Gulf oil spill exposure in workers who participated in its cleanup work.

Methods

Medical charts of both the oil spill exposed and unexposed subjects were reviewed. The changes in the white blood cells, platelets, hemoglobin, hematocrit, blood urea nitrogen, creatinine, alkaline phosphatase (ALP), aspartate amino transferase (AST), alanine amino transferase (ALT) levels, as well as their pulmonary and cardiac functions were evaluated.

Results

Medical records from 88 subjects (oil spill cleanup workers, n = 44 and unexposed, n = 44) were reviewed during initial and 7 years follow up visits after the disaster occurred. Compared with the unexposed subjects, oil spill exposed subjects had significantly reduced platelet counts (×10³/µL) at their initial (254.1 ± 46.7 versus 289.7 ± 63.7, P = 0.000) and follow-up (242.9 ± 55.6 versus 278.4 ± 67.6, P = 0.000) visits compared with the unexposed subjects (254.6 ± 51.9 versus 289.7 ± 63.7, P = 0.008). The hemoglobin and hematocrit levels were increased significantly both at their initial and follow-up visits in the oil spill exposed subjects compared to the unexposed subjects. Similarly, the oil spill exposed subjects had significantly increased ALP, AST, and ALT levels at their initial and follow-up visits compared with those of the unexposed subjects. Illness symptoms that were reported during their initial visit still persisted at their 7-year follow-up visit. Notably, at their 7-year follow-up visit, most of the oil spill exposed subjects had also developed chronic rhinosinusitis and reactive airway dysfunction syndrome as new symptoms that were not reported during their initial visit. Additionally, more abnormalities in pulmonary and cardiac functions were also seen in the oil spill exposed subjects.

Conclusion

This long-term follow-up study demonstrates that those people involved in the oil spill cleanup operations experiences persistent alterations or worsening of their hematological, hepatic, pulmonary, and cardiac functions. In addition, these subjects experienced prolonged or worsening illness symptoms even 7 years after their exposure to the oil spill.

Levels of 1-hydroxypyrene in urine of people living in an oil producing region of the Andean Amazon (Ecuador and Peru)

PURPOSE

Polycyclic aromatic hydrocarbons (PAHs) are contaminants with carcinogenic effects but little is known about their presence in environments surrounding oil drilling operations and spills or exposure levels in nearby communities. The objective of this study was to characterize PAH levels in people living near oil drilling operations in relation to fish consumption, occupation, source of water and other socio-demographic characteristics.

METHODS

This pilot study examined PAH exposure by measuring 1-hydroxypyrene (1-OHP) in urine samples using high-performance liquid chromatography and fluorescence detection from 75 women and men in the Ecuadorian and Peruvian Amazon living near oil drilling operations and who answered a questionnaire collecting socio-demographic, occupational and dietary information. Data were analyzed using multiple linear regression models.

RESULTS

The mean value of 1-OHP was 0.40 μmol/mol creatinine, 95% CI 0.32-0.46 μmol/mol creatinine. Women who used water from a surface source (for washing clothes or bathing) had almost twice the amount of 1-OHP in their urine (mean 1-OHP = 0.41 μmol/mol creatinine, 95% CI 0.28-0.54 μmol/mol creatinine, n = 23) as women who used water from either a well, a spring or rain (mean 1-OHP = 0.22 μmol/mol creatinine, 95% CI 0.11-0.34 μmol/mol creatinine, n = 6). Men who reported eating a bottom-dwelling species as their most commonly consumed fish (mean 1-OHP = 0.50 μmol/mol creatinine, 95% CI 0.36-0.64 μmol/mol creatinine, n = 31) had twice as much 1-OHP in their urine as men who reported a pelagic fish (mean 1-OHP = 0.25 μmol/mol creatinine, 95% CI 0.15-0.35 μmol/mol creatinine, n = 15), signaling either oral (fish consumption) or dermal (while standing in water fishing benthic species) exposure.

CONCLUSIONS

More contact with surface water and benthic fish may result in higher levels of 1-OHP in human urine among the study population. Reducing the amount of oil and wastes entering the waterways in Andean Amazonia would be one way to reduce exposure.

The Deepwater Horizon Oil Spill Coast Guard Cohort study

OBJECTIVES

Long-term studies of oil spill responders are urgently needed as oil spills continue to occur. To this end, we established the prospective Deepwater Horizon (DWH) Oil Spill Coast Guard Cohort study.

METHODS

DWH oil spill responders (n=8696) and non-responders (n=44 823) who were members of the US Coast Guard (20 April-17 December 2010) were included. This cohort uses both prospective, objective health data from military medical encounters and cross-sectional survey data. Here, we describe the cohort, present adjusted prevalence ratios (PRs) estimating cross-sectional associations between crude oil exposure (none, low/medium, high) and acute physical symptoms, and present adjusted relative risks (RRs) based on longitudinal medical encounter data (2010-2012) for responders/non-responders and responders exposed/not exposed to crude oil.

RESULTS

Responders and non-responders in this large cohort (n=53 519) have similar characteristics. Crude oil exposure was reported by >50% of responders. We found statistically significant associations for crude oil exposure with coughing (PR_high=1.78), shortness of breath (PR_high=2.30), wheezing (PR_high=2.32), headaches (PR_high=1.46), light-headedness/dizziness (PR_high=1.96), skin rash/itching (PR_high=1.87), diarrhoea (PR_high=1.76), stomach pain (PR_high=1.67), nausea/vomiting (PR_high=1.48) and painful/burning urination (PR_high=2.89) during deployment. Longitudinal analyses revealed that responders had elevated RRs for dermal conditions (RR=1.09), as did oil-exposed responders for chronic respiratory conditions (RR=1.32), asthma (RR=1.83) and dermal conditions (RR=1.21).

CONCLUSIONS

We found positive associations between crude oil exposure and various acute physical symptoms among responders, as well as longer term health effects. This cohort is well positioned to evaluate both short-term and long-term effects of oil spill exposures using both self-reported and clinical health data.

The impact of dissolved inorganic nitrogen and phosphorous on responses of microbial plankton to the Texas City "Y" oil spill in Galveston Bay, Texas (USA)

Ongoing bioremediation research seeks to promote naturally occurring microbial polycyclic aromatic hydrocarbon (PAH) degradation during and after oil spill events. However, complex relationships among functionally different microbial groups, nutrients and PAHs remain unconstrained. We conducted a surface water survey and corresponding nutrient amendment bioassays following the Texas City "Y" oil spill in Galveston Bay, Texas. Resident microbial groups, defined as either heterotrophic or autotrophic were enumerated by flow cytometry. Heterotrophic abundance was increased by oil regardless of nutrient concentrations. Contrastingly, autotrophic abundance was inhibited by oil, but this reaction was less severe when nutrient concentrations were higher. Several PAH compounds were reduced in nutrient amended treatments relative to controls suggesting nutrient enhanced microbial PAH processing. These findings provide a first-look at nutrient limitation during microbial oil processing in Galveston Bay, an important step in understanding if nutrient additions would be a useful bioremediation strategy in this and other estuarine systems.

Human health and ecological assessment programs for Hebei Spirit oil spill accident of 2007: Status, lessons, and future challenges

Hebei Spirit oil spill (HSOS) of December 2007 is one of the worst oil spill accidents that occurred in Yellow Sea. The affected coastline along the west coast of Korean Peninsula hosts one of the largest tidal flats worldwide, and is home to tens of thousands of human residents. Based on nation-wide concerns on ecosystem damages and adverse human health effects, two separate surveillance programs on ecosystem and human health were initiated: a 10-year follow-up program by Ministry of Oceans and Fisheries to assess ecological impacts of the oil spill, and an exposure and health effect assessment program by Ministry of Environment for the residents of Taean and its vicinity. For the past eight years, extensive monitoring and surveillance data on ecosystem and humans have been accumulated through these programs. But these studies have been conducted mostly independently, and collaborations were seldom made between two programs. The lack of communication resulted in gaps and overlaps between the programs which led to loss of critical information and efficiency. As oil spill can affect both humans and ecosystem through various pathways, collaboration and communication between human and ecosystem health surveillance programs are necessary, and will synergize the success of both programs. Such concerted efforts will provide better platform for understanding the status of impact, and for developing approaches to address human and ecosystem health challenges that may be faced following environmental disasters like HSOS.

Urinary oxidative stress biomarkers among local residents measured 6years after the Hebei Spirit oil spill

In December 2007, the Hebei Spirit oil spill occurred on the west coast of South Korea. Association between crude oil exposure and the levels of urinary oxidative stress biomarkers was reported among the local residents, 1.5years after the accident. The aim of this study was to follow-up possible longer-term effects of the oil spill among the residents near the oil spill. Six years after the accident, urinary oxidative stress biomarkers of the residents were associated with surrogates of oil exposure. The target subjects were divided into two groups based on the distance of their residence to the spill site, i.e., those near the spill site ('Near' group, n=476), and those far from the spill ('Far' group, n=152). A questionnaire was administered by trained interviewers or self-reporting, and demographic information and other parameters of the participants, such as socioeconomic status, smoking and drinking behaviors, disease history, and duration of clean-up activities after the spill, were collected. The participants' levels of 8-hydroxy-2-deoxyguanosine (8-OHdG) and malondialdehyde (MDA) in 12 h urine samples were measured as indicators of oxidative DNA damage and lipid peroxidation, respectively. A general linear model was used for statistical analysis. Urinary MDA and 8-OHdG levels measured from 'Near' group, i.e., geometric mean of 2.19μmol/g creatinine, and 5.41μg/g creatinine, respectively, were higher than those of 'Far' group. Especially, urinary 8-OHdG levels in the 'Near' group were significantly higher than those of 'Far' after adjusting relevant covariates. In addition, the duration of clean-up activities showed a significant association with both urinary 8-OHdG and MDA levels. Even 6years after the oil spill, positive associations between oxidative stress biomarkers and surrogates of oil exposure were evident. While the present study design lacks biomarkers of exposure, the results of this study suggest that the consequences of oil pollution may last for years.

Effects of exposure to oil spills on human health: Updated review

Oil spills may involve health risks for people participating in the cleanup operations and coastal inhabitants, given the toxicological properties of the oil components. In spite of this, only after a few major oil spills (crude oil or fuel oil no. 6) have studies on effects of exposure to diverse aspects of human health been performed. Previously, Aguilera et al. (2010) examined all documents published to that date dealing with any type of human health outcome in populations exposed to oil spills. The aim of the present review was to compile all new information available and determine whether evidence reported supports the existence of an association between exposure and adverse human health risks. Studies were classified in three groups according to type of health outcome addressed: (i) effects on mental health, (ii) physical/physiological effects, and (iii) genotoxic, immunotoxic, and endocrine toxicity. New studies published on oil-spill-exposed populations-coastal residents in the vicinity of the spills or participants in cleanup operations-provide additional support to previous evidence on adverse health effects related to exposure regarding different parameters in all three categories considered. Some of the observed effects even indicated that several symptoms may persist for some years after exposure. Hence, (1) health protection in these individuals should be a matter of concern; and (2) health risk assessment needs to be carried out not only at the time of exposure but also for prolong periods following exposure, to enable early detection of any potential exposure-related harmful effects.

Oxidative stress biomarkers in long-term participants in clean-up work after the Hebei Spirit oil spill

BACKGROUND

The oil tanker Hebei Spirit spilled 12,547kL of oil near the western coastline of Korea on December 7, 2007. We aimed to investigate the relationship between oil spill exposure and oxidative stress in residents living near the affected area.

METHODS

Study subjects were 671 residents who participated in a health examination between February and September 2009. As surrogates for oil spill exposure, we used the total duration of clean-up work and levels of urinary metabolites of polycyclic aromatic hydrocarbons (PAHs), 1-hydroxypyrene (1-OHP) and 2-naphthol (2-NAPH). Oxidative stress was measured using urinary levels of malondialdehyde (MDA) and 8-hydroxy-2'-deoxyguanosine (8-OHdG), indicators of lipid peroxidation and oxidative DNA damage, respectively.

RESULTS

Levels of oxidative stress biomarkers were significantly increased with longer involvement in clean-up work over one year after the Hebei Spirit oil spill (MDA, p-trend<0.0001; 8-OHdG, p-trend<0.0001). As more time elapsed since the last involvement in clean-up, the total duration of clean-up work participation and levels of PAH metabolites (1-OHP and 2-NAPH), as well as levels of the oxidative stress biomarkers (MDA and 8-OHdG) decreased further. The level of 1-OHP had a significant positive correlation with the total duration of clean-up work involvement, with a higher level found in those who participated in clean-up for >100 days. Increasing levels of 1-OHP were significantly associated with increased MDA and 8-OHdG after adjusting for covariates, while the strength of association weakened as time passed since the last participation in clean-up work. The significance of the association was maintained for up to 12 months after the last clean-up work.

CONCLUSIONS

The results suggested that oil exposure from prolonged clean-up activity likely induced oxidative stress in clean-up participants up to at least one year after the last exposure.