Initial study on the effects of Prestige oil on human health

Risk of longer-term endocrine and metabolic conditions in the Deepwater Horizon Oil Spill Coast Guard cohort study - five years of follow-up

INTRODUCTION

Long-term endocrine and metabolic health risks associated with oil spill cleanup exposures are largely unknown, despite the endocrine-disrupting potential of crude oil and oil dispersant constituents. We aimed to investigate risks of longer-term endocrine and metabolic conditions among U.S. Coast Guard (USCG) responders to the Deepwater Horizon (DWH) oil spill.

METHODS

Our study population included all active duty DWH Oil Spill Coast Guard Cohort members (N = 45,224). Self-reported spill exposures were ascertained from post-deployment surveys. Incident endocrine and metabolic outcomes were defined using International Classification of Diseases (9th Revision) diagnostic codes from military health encounter records up to 5.5 years post-DWH. Using Cox proportional hazards regression, we estimated adjusted hazard ratios (aHR) and 95% confidence intervals (CIs) for various incident endocrine and metabolic diagnoses (2010-2015, and separately during 2010-2012 and 2013-2015).

RESULTS

The mean baseline age was 30 years (~ 77% white, ~ 86% male). Compared to non-responders (n = 39,260), spill responders (n = 5,964) had elevated risks for simple and unspecified goiter (aHR = 2.09, 95% CI: 1.29-3.38) and disorders of lipid metabolism (aHR = 1.09, 95% CI: 1.00-1.18), including its subcategory other and unspecified hyperlipidemia (aHR = 1.10, 95% CI: 1.01-1.21). The dysmetabolic syndrome X risk was elevated only during 2010-2012 (aHR = 2.07, 95% CI: 1.22-3.51). Responders reporting ever (n = 1,068) vs. never (n = 2,424) crude oil inhalation exposure had elevated risks for disorders of lipid metabolism (aHR = 1.24, 95% CI: 1.00-1.53), including its subcategory pure hypercholesterolemia (aHR = 1.71, 95% CI: 1.08-2.72), the overweight, obesity and other hyperalimentation subcategory of unspecified obesity (aHR = 1.52, 95% CI: 1.09-2.13), and abnormal weight gain (aHR = 2.60, 95% CI: 1.04-6.55). Risk estimates for endocrine/metabolic conditions were generally stronger among responders reporting exposure to both crude oil and dispersants (vs. neither) than among responders reporting only oil exposure (vs. neither).

CONCLUSION

In this large cohort of active duty USCG responders to the DWH disaster, oil spill cleanup exposures were associated with elevated risks for longer-term endocrine and metabolic conditions.

Development of a method for detecting and classifying hydrocarbon-contaminated soils via laser-induced breakdown spectroscopy and machine learning algorithms

In recent years, there has been a significant increase in oil exploration and exploitation activities, resulting in spills that pose a severe threat to the environment and public health. The present work aims to develop a method to detect and classify hydrocarbon-contaminated soils that is useful for analyzing contaminated sites. The method combines machine learning algorithms with data obtained via the laser-induced breakdown spectroscopy (LIBS) technique. The first stage involved optimizing the experimental parameters of the LIBS technique from eleven soil samples contaminated with different hydrocarbons and one sample used for control purposes. To classify the samples effectively, a robust and interpretable method was required. Linear discriminant analysis (LDA) was chosen for its ability to identify the linear combination of features that best separates classes while maintaining simplicity and interpretability. To address overfitting risks and reduce dimensionality, principal component analysis (PCA) was applied before LDA. This preprocessing step optimized the classification of samples contaminated with eleven different hydrocarbon sources and distinguished them from the control class. The results revealed accuracies greater than 90%. The model was also used to discriminate subsets of classes that shared similarities, which could be revealed from the analysis of the entire class set. The approach also successfully classified related classes, such as gasoline and different oils, achieving 100% accuracy in all cases. This enhanced capacity to identify and differentiate hydrocarbons with LIBS and machine learning marks a significant advancement in environmental monitoring.

Impact of genetic polymorphisms on associations between crude oil exposure and health effects among Coast Guard Deepwater Horizon responders

The U.S. Coast Guard led a clean-up response to the Deepwater Horizon (DWH) oil spill, the largest marine oil spill in history. Studies from the Deepwater Horizon Coast Guard Cohort (DWH-CG) have shown associations between crude oil exposure and various acute symptoms and longer-term health outcomes. Evidence has suggested genetic polymorphisms in metabolizing genes could modify the toxicity of crude oil and its components, which could impact health effects in responders exposed to crude oil. We applied log-binomial regression to calculate prevalence ratios (PRs) and 95 % confidence intervals (CIs) in the relationship between crude oil exposure (categorized to never, low, and high) and four acute symptoms (cough, shortness of breath/wheeze, skin rash/itching, headache) and to calculate risk ratios (RR) and 95 % CIs in the relationship between crude oil exposure and incidence of hypertension and asthma in the DWH-CG cohort. Effect modification by polymorphisms in 6 metabolizing genes [Cytochrome P450 family 2 subfamily E member 1 (CYP2E1), Glutathione S-Transferase Mu 1 (GSTM1), Glutathione S-Transferase Theta 1 (GSTT1), Epoxide Hydrolase 1 (EPHX1), NADPH quinone oxidoreductase-1 (NQO1), and Myeloperoxidase (MPO)] was evaluated. Results were stratified into wildtype and variant [i.e., those with at least one variant allele] for each gene. There was evidence of effect modification in the relationship between crude oil exposure and asthma by CYP2E1 [wildtype (RRHigh vs never/low, 95 % CI = 1.18, 0.99-1.42); variant (RRHigh vs never/low, 95 % CI = 2.27, 1.26-4.10); pinteraction = 0.04] and headache by NQO1 [wildtype (PRHigh vs never/low, 95 % CI = 2.1, 1.88-2.34); variant (PRHigh vs never/low, 95 % CI = 1.44, 1.07-1.94); pinteraction = 0.04]. Our study indicated the potential effect modification by metabolizing genotype in the relationship between crude oil exposure and headaches or asthma. These findings underscore the importance of considering potential genetic susceptibility among oil spill responders. Genotype variations, which are revealed only via specialized testing and thus not readily apparent, may contribute to differential vulnerability to the health effects associated with oil spill exposures.

Endocrine disruptors, aryl hydrocarbon receptor and cortisol secretion

PURPOSE

Endocrine disruptors exert a plethora of effects in endocrine tissues, from altered function to carcinogenesis. Given its lipophilic nature, the adrenal cortex represents an ideal target for endocrine disruptors and thus, possibly, xenobiotic-induced adrenocortical dysfunction. However, there is no clear understanding of the effect of endocrine disruptors on adrenal steroidogenesis, in particular as regards the aryl hydrocarbon receptor (AHR) pathway, one of the key mediators.

METHODS

The present review recapitulates available evidence on the effects of AHR ligands on adrenal steroidogenesis, with focus on cortisol secretion.

RESULTS

Short-term exposure to AHR ligands most often induced a stress-like corticosteroid response followed by decreased responsiveness to stressors with long-term exposure. This was observed in several experimental models across species as well as in animals and humans in real-life settings. Prenatal exposure led to different effects according to sex of the offspring, as observed in murine models and in children from mothers in several countries. In vitro findings proved highly dependent on the experimental setting, with reduced cortisol response and steroidogenic enzyme synthesis mostly observed in fish and increased cortisol synthesis and secretion observed in murine and human adrenal cell lines. Of note, no AHR-binding element was detected in steroidogenic enzyme promoters, suggesting the involvement of additional factors.

CONCLUSION

Our review provides evidence for the impact of AHR ligands on adrenocortical function and indicates further avenues of research to better clarify its effects.

Factor diagnosis and governance strategies of ship oil spill accidents based on formal concept analysis

Ship oil spill accidents have a prolonged duration, complex consequences, challenging cleaning and repairing efforts, and pose a significant threat to the environment, economy, and society. Eliminating irrelevant information and identifying key factors using traditional methods is challenging due to the complexity of the causes of ship oil spill accidents. To address this, this article sorts out the accident databases of the International Tanker Owners Pollution Federation (ITOPF) and eight national maritime administration agencies, and innovatively constructs a formal concept analysis (FCA) model based on reports of 100-plus ship oil spill accidents. The model results prove that improper operation, less complete ship equipment, large tonnage, and poor navigation conditions are the key factors. The different causal rules of oil spills in collision/contact, grounding, fire/explosion, and foundering are further compared and analyzed. Finally, corresponding improvement measures are put forward for the key factors of oil spills and different causal rules.

Bioremediation by oil degrading marine bacteria: An overview of supplements and pathways in key processes

Oil spillage is one of the most common pollutants which brings greater economic loss and damage to the environment. The intensity and amount of the damage may vary depending on factors such as the type of oil, the location of the spill, and the climatic parameters in the area. As for any pollution management, the guidelines are Reduce, Re-use, Recover and Disposal. Amongst the other remediation processes, Bioremediation is amongst the most significant environmentally friendly and cost-effective approaches for marine biological restoration because it allows complex petroleum hydrocarbons in spilt oil to decompose completely into harmless compounds. Mainly, the necessity and essence of bioremediation were talked about. This review discussed the bacteria identified which are capable of degrading various oil related pollutants and their components. Also, it covered the various media components used for screening and growing the oil degrading bacteria and the pathways that are associated with oil degradation. This article also reviewed the recent research carried out related to the oil degrading bacteria.

Effects of Chlorella vulgaris Enhancement on Endogenous Microbial Degradation of Marine Oil Spills and Community Diversity

Biofortification could improve the bioremediation efficiency of microbes in the reparation of marine environmental damage caused by oil spills. In this paper, Chlorella vulgaris LH-1 was used as a fortifier to enhance the degradation of a marine oil spill by endogenous microorganisms. The addition of C. vulgaris LH-1 increased the degradation efficiency of crude oil by 11.09–42.41% and considerably accelerated oil degradation efficiency. Adding C. vulgaris LH-1 to a crude oil environment can improve the activity of endogenous seawater microorganisms. The results of high-throughput sequencing showed that the main bacterial genera were Oceanicola, Roseibacillus, and Rhodovulum when exotrophic C. vulgaris LH-1 and seawater endogenous microorganisms degraded low-concentration crude oil together. However, the addition of high-concentration nutrient salts changed the main bacterial genera in seawater to unclassified Microbacterium, Erythrobacter, and Phaeodactylibacter. The addition of C. vulgaris LH-1 increased the abundance of marine bacteria, Rhodococcus, and Methylophaga and decreased the abundance of Pseudomonas, Cladosporium, and Aspergillus. The functional prediction results of phylogenetic investigation of communities by reconstruction of unobserved states indicated that C. vulgaris LH-1 could improve the metabolic ability of seawater endogenous microorganisms to degrade endogenous bacteria and fungi in crude oil.

Estimates of Occupational Inhalation Exposures to Six Oil-Related Compounds on the Four Rig Vessels Responding to the Deepwater Horizon Oil Spill

BACKGROUND

The 2010 Deepwater Horizon (DWH) oil spill involved thousands of workers and volunteers to mitigate the oil release and clean-up after the spill. Health concerns for these participants led to the initiation of a prospective epidemiological study (GuLF STUDY) to investigate potential adverse health outcomes associated with the oil spill response and clean-up (OSRC). Characterizing the chemical exposures of the OSRC workers was an essential component of the study. Workers on the four oil rig vessels mitigating the spill and located within a 1852 m (1 nautical mile) radius of the damaged wellhead [the Discoverer Enterprise (Enterprise), the Development Driller II (DDII), the Development Driller III (DDIII), and the HelixQ4000] had some of the greatest potential for chemical exposures.

OBJECTIVES

The aim of this paper is to characterize potential personal chemical exposures via the inhalation route for workers on those four rig vessels. Specifically, we presented our methodology and descriptive statistics of exposure estimates for total hydrocarbons (THCs), benzene, toluene, ethylbenzene, xylene, and n-hexane (BTEX-H) for various job groups to develop exposure groups for the GuLF STUDY cohort.

METHODS

Using descriptive information associated with the measurements taken on various jobs on these rig vessels and with job titles from study participant responses to the study questionnaire, job groups [unique job/rig/time period (TP) combinations] were developed to describe groups of workers with the same or closely related job titles. A total of 500 job groups were considered for estimation using the available 8139 personal measurements. We used a univariate Bayesian model to analyze the THC measurements and a bivariate Bayesian regression framework to jointly model the measurements of THC and each of the BTEX-H chemicals separately, both models taking into account the many measurements that were below the analytic limit of detection.

RESULTS

Highest THC exposures occurred in TP1a and TP1b, which was before the well was mechanically capped. The posterior medians of the arithmetic mean (AM) ranged from 0.11 ppm ('Inside/Other', TP1b, DDII; and 'Driller', TP3, DDII) to 14.67 ppm ('Methanol Operations', TP1b, Enterprise). There were statistical differences between the THC AMs by broad job groups, rigs, and time periods. The AMs for BTEX-H were generally about two to three orders of magnitude lower than the THC AMs, with benzene and ethylbenzene measurements being highly censored.

CONCLUSIONS

Our results add new insights to the limited literature on exposures associated with oil spill responses and support the current epidemiologic investigation of potential adverse health effects of the oil spill.

Biodegradation Potential of Bacillus sp. PAH-2 on PAHs for Oil-Contaminated Seawater

Microbial degradation is a useful tool for inhibiting or preventing polycyclic aromatic hydrocarbons (PAHs) widely distributed in marine environment after oil spill accidents. This study aimed to evaluate the potential and diversity of bacteria Bacillus sp. PAH-2 on Benzo (a) anthracene (BaA), Pyrene (Pyr), and Benzo (a) pyrene (BaP), their composite system, aromatic components system, and crude oil. The seven-day degradation rates against BaA, Pyr, and BaP were 20.6%, 12.83%, and 17.49%, respectively. Further degradation study of aromatic components demonstrated PAH-2 had a high degradation rate of substances with poor stability of molecular structure. In addition, the degradation of PAHs in crude oil suggested PAH-2 not only made good use of PAHs in such a more complex structure of pollutants but the saturated hydrocarbons in the crude oil also showed a good application potential.

Human Health and Ocean Pollution

Background

Pollution - unwanted waste released to air, water, and land by human activity - is the largest environmental cause of disease in the world today. It is responsible for an estimated nine million premature deaths per year, enormous economic losses, erosion of human capital, and degradation of ecosystems. Ocean pollution is an important, but insufficiently recognized and inadequately controlled component of global pollution. It poses serious threats to human health and well-being. The nature and magnitude of these impacts are only beginning to be understood.

Goals

(1) Broadly examine the known and potential impacts of ocean pollution on human health. (2) Inform policy makers, government leaders, international organizations, civil society, and the global public of these threats. (3) Propose priorities for interventions to control and prevent pollution of the seas and safeguard human health.

Methods

Topic-focused reviews that examine the effects of ocean pollution on human health, identify gaps in knowledge, project future trends, and offer evidence-based guidance for effective intervention.

Environmental Findings

Pollution of the oceans is widespread, worsening, and in most countries poorly controlled. It is a complex mixture of toxic metals, plastics, manufactured chemicals, petroleum, urban and industrial wastes, pesticides, fertilizers, pharmaceutical chemicals, agricultural runoff, and sewage. More than 80% arises from land-based sources. It reaches the oceans through rivers, runoff, atmospheric deposition and direct discharges. It is often heaviest near the coasts and most highly concentrated along the coasts of low- and middle-income countries. Plastic is a rapidly increasing and highly visible component of ocean pollution, and an estimated 10 million metric tons of plastic waste enter the seas each year. Mercury is the metal pollutant of greatest concern in the oceans; it is released from two main sources - coal combustion and small-scale gold mining. Global spread of industrialized agriculture with increasing use of chemical fertilizer leads to extension of Harmful Algal Blooms (HABs) to previously unaffected regions. Chemical pollutants are ubiquitous and contaminate seas and marine organisms from the high Arctic to the abyssal depths.

Ecosystem Findings

Ocean pollution has multiple negative impacts on marine ecosystems, and these impacts are exacerbated by global climate change. Petroleum-based pollutants reduce photosynthesis in marine microorganisms that generate oxygen. Increasing absorption of carbon dioxide into the seas causes ocean acidification, which destroys coral reefs, impairs shellfish development, dissolves calcium-containing microorganisms at the base of the marine food web, and increases the toxicity of some pollutants. Plastic pollution threatens marine mammals, fish, and seabirds and accumulates in large mid-ocean gyres. It breaks down into microplastic and nanoplastic particles containing multiple manufactured chemicals that can enter the tissues of marine organisms, including species consumed by humans. Industrial releases, runoff, and sewage increase frequency and severity of HABs, bacterial pollution, and anti-microbial resistance. Pollution and sea surface warming are triggering poleward migration of dangerous pathogens such as the Vibrio species. Industrial discharges, pharmaceutical wastes, pesticides, and sewage contribute to global declines in fish stocks.

Human Health Findings

Methylmercury and PCBs are the ocean pollutants whose human health effects are best understood. Exposures of infants in utero to these pollutants through maternal consumption of contaminated seafood can damage developing brains, reduce IQ and increase children's risks for autism, ADHD and learning disorders. Adult exposures to methylmercury increase risks for cardiovascular disease and dementia. Manufactured chemicals - phthalates, bisphenol A, flame retardants, and perfluorinated chemicals, many of them released into the seas from plastic waste - can disrupt endocrine signaling, reduce male fertility, damage the nervous system, and increase risk of cancer. HABs produce potent toxins that accumulate in fish and shellfish. When ingested, these toxins can cause severe neurological impairment and rapid death. HAB toxins can also become airborne and cause respiratory disease. Pathogenic marine bacteria cause gastrointestinal diseases and deep wound infections. With climate change and increasing pollution, risk is high that Vibrio infections, including cholera, will increase in frequency and extend to new areas. All of the health impacts of ocean pollution fall disproportionately on vulnerable populations in the Global South - environmental injustice on a planetary scale.

Conclusions

Ocean pollution is a global problem. It arises from multiple sources and crosses national boundaries. It is the consequence of reckless, shortsighted, and unsustainable exploitation of the earth's resources. It endangers marine ecosystems. It impedes the production of atmospheric oxygen. Its threats to human health are great and growing, but still incompletely understood. Its economic costs are only beginning to be counted.Ocean pollution can be prevented. Like all forms of pollution, ocean pollution can be controlled by deploying data-driven strategies based on law, policy, technology, and enforcement that target priority pollution sources. Many countries have used these tools to control air and water pollution and are now applying them to ocean pollution. Successes achieved to date demonstrate that broader control is feasible. Heavily polluted harbors have been cleaned, estuaries rejuvenated, and coral reefs restored.Prevention of ocean pollution creates many benefits. It boosts economies, increases tourism, helps restore fisheries, and improves human health and well-being. It advances the Sustainable Development Goals (SDG). These benefits will last for centuries.

Recommendations

World leaders who recognize the gravity of ocean pollution, acknowledge its growing dangers, engage civil society and the global public, and take bold, evidence-based action to stop pollution at source will be critical to preventing ocean pollution and safeguarding human health.Prevention of pollution from land-based sources is key. Eliminating coal combustion and banning all uses of mercury will reduce mercury pollution. Bans on single-use plastic and better management of plastic waste reduce plastic pollution. Bans on persistent organic pollutants (POPs) have reduced pollution by PCBs and DDT. Control of industrial discharges, treatment of sewage, and reduced applications of fertilizers have mitigated coastal pollution and are reducing frequency of HABs. National, regional and international marine pollution control programs that are adequately funded and backed by strong enforcement have been shown to be effective. Robust monitoring is essential to track progress.Further interventions that hold great promise include wide-scale transition to renewable fuels; transition to a circular economy that creates little waste and focuses on equity rather than on endless growth; embracing the principles of green chemistry; and building scientific capacity in all countries.Designation of Marine Protected Areas (MPAs) will safeguard critical ecosystems, protect vulnerable fish stocks, and enhance human health and well-being. Creation of MPAs is an important manifestation of national and international commitment to protecting the health of the seas.

Developing Large-Scale Research in Response to an Oil Spill Disaster: a Case Study

Research conducted in the wake of a disaster can provide information to help mitigate health consequences, support future recovery efforts, and improve resilience. However, a number of barriers have prevented time-sensitive research responses following previous disasters. Furthermore, large-scale disasters present their own special challenges due to the number of people exposed to disaster conditions, the number of groups engaged in disaster response, and the logistical challenges of rapidly planning and implementing a large study. In this case study, we illustrate the challenges in planning and conducting a large-scale post-disaster research study by drawing on our experience in establishing the Gulf Long-term Follow-up (GuLF) Study following the 2010 Deepwater Horizon disaster. We describe considerations in identifying at-risk populations and appropriate comparison groups, garnering support for the study from different stakeholders, obtaining timely scientific and ethics review, measuring and characterizing complex exposures, and addressing evolving community health concerns and unmet medical needs. We also describe the NIH Disaster Research Response (DR2) Program, which provides a suite of resources, including data collection tools, research protocols, institutional review board guidance, and training materials to enable the development and implementation of time-critical studies following disasters and public health emergencies. In describing our experiences related to the GuLF Study and the ongoing efforts through the NIH DR2 Program, we aim to help improve the timeliness, quality, and value of future disaster-related data collection and research studies.

Determinants of airborne benzene evaporating from fresh crude oils released into seawater

Benzene, toluene, ethylbenzene, xylenes, naphthalene and n-hexane evaporating from a thin oil film was measured for 30 min in a small-scale test system at 2 and 13 °C and the impact of physicochemical properties on airborne benzene with time after bulk oil release was studied. Linear mixed-effects models for airborne benzene in three time periods; first 5, first 15 and last 15 min of sampling, indicated that benzene content in fresh oil, oil group (condensate/light crude oil) and pour point were significant determinants explaining 63-73% of the total variance in the outcome variables. Oils with a high pour point evaporated considerably slower than oils with a low pour point. The mean air concentration of total volatile organic compounds was significatly higher at 13 °C (735 ppm) compared to 2 °C (386 ppm) immediately after release of oil, but at both temperatures the concentration rapidly declined.

Reflectance and imaging spectroscopy applied to detection of petroleum hydrocarbon pollution in bare soils

Accidental releases of hazardous waste related to the extraction, refining, and transport of oil and gas are inevitable. Petroleum facilities and intrinsic pipelines present environmental pollution risks, threatening both human health and ecosystems. Research has been undertaken to enhance the conventional methods for monitoring hazardous waste problems and to improve time-consuming and cost-effective ways for leak detection and remediation process. In this study, both diffuse and imaging (hyperspectral) reflectance spectroscopy are used for detection and characterization of petroleum hydrocarbon (PHC) contamination in latosols. Laboratory and field measurements of PHC-contaminated and PHC-free soils were collected from an oil facility using an ASD FieldSpec-3 high-resolution portable spectrometer (2150 channels) covering visible, near infrared and shortwave infrared wavelengths (VNIR-SWIR: 350-2500 nm). The hyperspectral image dataset was acquired with the ProSpecTIR-VS airborne sensor using 357 channels in the VNIR-SWIR range at 1 m of spatial resolution. Narrow intervals of reflectance spectra were analyzed to identify the primary mineral and PHC absorption bands in soil samples and to investigate the spectral match with airborne hyperspectral data. The Multiple Endmember Spectral Mixture Analysis (MESMA) method was employed in three hierarchical levels to classify the hyperspectral imagery. The classification product yielded from MESMA model at the fourth level was 98% accurate in discriminating contaminated soils. The results demonstrated the applicability of both diffuse reflectance and imaging (hyperspectral) spectroscopy to identify bare soils contaminated by PHC leaks and spills. These technologies can also provide useful information for remediation initiatives, thereby avoiding further problems with hazardous waste.

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.

Petroleum oil and mercury pollution from shipwrecks in Norwegian coastal waters

Worldwide there are tens of thousands of sunken shipwrecks lying on the coastal seabed. These potentially polluting wrecks (PPW) are estimated to hold 3-25milliont of oil. Other hazardous cargo in PPW includes ordnance, chemicals and radioactive waste. Here, we present and discuss studies on mercury (Hg) and oil pollution in coastal marine sediment caused by two of the >2100 documented PPW in Norwegian marine waters. The German World War II (WWII) submarine (U-864) lies at about 150m below the sea surface, near the Norwegian North Sea island of Fedje. The submarine is estimated to have been carrying 67t of elemental Hg, some of which has leaked on to surrounding sediment. The total Hg concentration in bottom surface sediment within a 200m radius of the wreckage decreases from 100g/kgd.w. at the wreckage hotspot to about 1mg/kgd.w. at 100m from the hotspot. The second wreck is a German WWII cargo ship (Nordvard), that lies at a depth of ca. 30m near the Norwegian harbor of Moss. Oil leakage from Nordvard has contaminated the bottom coastal sediment with polycyclic aromatic hydrocarbons (PAH). The findings from this study provide useful insight to coastal administration authorities involved in assessing and remediating wreck-borne pollution from any of the tens of thousands of sunken shipwrecks.

Oil Spill Field Trial at Sea: Measurements of Benzene Exposure

Objectives

Characterize personal exposure to airborne hydrocarbons, particularly carcinogenic benzene, during spill of two different fresh crude oils at sea.

Methods

The study included 22 participants taking part in an «oil on water» field trial in the North Sea. Two types of fresh crude oils (light and heavy) were released six times over two consecutive days followed by different oil spill response methods. The participants were distributed on five boats; three open sampling boats (A, B, and C), one release ship (RS), and one oil recovery (OR) vessel. Assumed personal exposure was assessed a priori, assuming high exposure downwind and close to the oil slick (sampling boats), low exposure further downwind (100-200 m) and upwind from the oil slick (main deck of RS and OR vessel), and background exposure indoors (bridge of RS/OR vessel). Continuous measurements of total volatile organic compounds in isobutylene equivalents were performed with photoionization detectors placed in all five boats. Full-shift personal exposure to benzene, toluene, ethylbenzene, xylenes, naphthalene, and n-hexane was measured with passive thermal desorption tubes.

Results

Personal measurements of benzene, averaged over the respective sample duration, on Day 1 showed that participants in the sampling boats (A, B, and C) located downwind and close to the oil slick were highest exposed (0.14-0.59 ppm), followed by participants on the RS main deck (0.02-0.10 ppm) and on the bridge (0.004-0.03 ppm). On Day 2, participants in sampling boat A had high benzene exposure (0.87-1.52 ppm) compared to participants in sampling boat B (0.01-0.02 ppm), on the ships (0.06-0.10 ppm), and on the bridge (0.004-0.01 ppm). Overall, the participants in the sampling boats had the highest exposure to all of the compounds measured. The light crude oil yielded a five times higher concentration of total volatile organic compounds in air in the sampling boats (max 510 ppm) than the heavy crude oil (max 100 ppm) but rapidly declined to <20 ppm within 24 min after release of oil, indicating short periods of exposure.

Conclusions

The personal exposure to benzene downwind and close to the oil slick during spills of light crude oil was relatively high, with concentration levels approaching the occupational exposure limits for several participants. For bulk spill scenarios like in this study, cleanup should not be initiated the first 30-60 min to allow for evaporation, while appropriate personal protective equipment should be used in continuous spills when working downwind and close to the oil slick.

The Gulf Long-Term Follow-Up Study (GuLF STUDY): Biospecimen collection at enrollment

The 2010 Deepwater Horizon (DWH) explosion in the Gulf of Mexico led to the largest ever marine oil spill by volume. The GuLF STUDY is investigating possible adverse human health effects associated with oil spill activities. One objective of the study was to utilize biological specimens from study participants to examine spill-related adverse health effects. This study describes the methods for collecting, processing, shipping, and storing specimens during the enrollment phase of the study. GuLF STUDY participants living in Gulf States (Alabama, Florida, Louisiana, Mississippi, and eastern Texas) were eligible to complete a home visit at enrollment, one to three years after the DWH explosion. During this visit, blood, urine, toenail and hair clippings, and house dust samples were collected. Specimens were shipped overnight to a central processing laboratory in containers with cold and ambient temperature compartments. Most blood and urine specimens were then aliquoted and stored in liquid nitrogen vapor or at -80°C, with some samples stored at -20°C. A total of 11,193 participants completed a home visit, and over 99% provided at least one biospecimen. Most participants provided blood (93%), urine (99%), and toenail clippings (89%), and 40% provided hair. Nearly all participants (95%) provided house-dust samples. Most samples were received by the laboratory one (58%) or two (25%) days after collection. These biospecimens enable investigation of a range of biomarkers of spill-related adverse health effects, and possibly some biomarkers of spill-related exposures. The biospecimen collection, handling, and storage protocols were designed to maximize current and future scientific value within logistical and budgetary constraints and might serve as a template for future studies conducted in similar time-critical and geographically dispersed settings.

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.

Microbial degradation of petroleum hydrocarbons

Petroleum hydrocarbon pollutants are recalcitrant compounds and are classified as priority pollutants. Cleaning up of these pollutants from environment is a real world problem. Bioremediation has become a major method employed in restoration of petroleum hydrocarbon polluted environments that makes use of natural microbial biodegradation activity. Petroleum hydrocarbons utilizing microorganisms are ubiquitously distributed in environment. They naturally biodegrade pollutants and thereby remove them from the environment. Removal of petroleum hydrocarbon pollutants from environment by applying oleophilic microorganisms (individual isolate/consortium of microorganisms) is ecofriendly and economic. Microbial biodegradation of petroleum hydrocarbon pollutants employs the enzyme catalytic activities of microorganisms to enhance the rate of pollutants degradation. This article provides an overview about bioremediation for petroleum hydrocarbon pollutants. It also includes explanation about hydrocarbon metabolism in microorganisms with a special focus on new insights obtained during past couple of years.

Carcinogenic effects of oil dispersants: A KEGG pathway-based RNA-seq study of human airway epithelial cells

The health impacts of the BP oil spill are yet to be further revealed as the toxicological effects of oil products and dispersants on human respiratory system may be latent and complex, and hence difficult to study and follow up. Here we performed RNA-seq analyses of a system of human airway epithelial cells treated with the BP crude oil and/or dispersants Corexit 9500 and Corexit 9527 that were used to help break up the oil spill. Based on the RNA-seq data, we then systemically analyzed the transcriptomic perturbations of the cells at the KEGG pathway level using two pathway-based analysis tools, GAGE (generally applicable gene set enrichment) and GSNCA (Gene Sets Net Correlations Analysis). Our results suggested a pattern of change towards carcinogenesis for the treated cells marked by upregulation of ribosomal biosynthesis (hsa03008) (p=1.97E-13), protein processing (hsa04141) (p=4.09E-7), Wnt signaling (hsa04310) (p=6.76E-3), neurotrophin signaling (hsa04722) (p=7.73E-3) and insulin signaling (hsa04910) (p=1.16E-2) pathways under the dispersant Corexit 9527 treatment, as identified by GAGE analysis. Furthermore, through GSNCA analysis, we identified gene co-expression changes for several KEGG cancer pathways, including small cell lung cancer pathway (hsa05222, p=9.99E-5), under various treatments of oil/dispersant, especially the mixture of oil and Corexit 9527. Overall, our results suggested carcinogenic effects of dispersants (in particular Corexit 9527) and their mixtures with the BP crude oil, and provided further support for more stringent safety precautions and regulations for operations involving long-term respiratory exposure to oil and dispersants.

Offshore oil spill response practices and emerging challenges

Offshore oil spills are of tremendous concern due to their potential impact on economic and ecological systems. A number of major oil spills triggered worldwide consciousness of oil spill preparedness and response. Challenges remain in diverse aspects such as oil spill monitoring, analysis, assessment, contingency planning, response, cleanup, and decision support. This article provides a comprehensive review of the current situations and impacts of offshore oil spills, as well as the policies and technologies in offshore oil spill response and countermeasures. Correspondingly, new strategies and a decision support framework are recommended for improving the capacities and effectiveness of oil spill response and countermeasures. In addition, the emerging challenges in cold and harsh environments are reviewed with recommendations due to increasing risk of oil spills in the northern regions from the expansion of the Arctic Passage.

Persistence of Breakage in Specific Chromosome Bands 6 Years after Acute Exposure to Oil

BACKGROUND

The identification of breakpoints involved in chromosomal damage could help to detect genes involved in genetic disorders, most notably cancer. Until now, only one published study, carried out by our group, has identified chromosome bands affected by exposure to oil from an oil spill. In that study, which was performed two years after the initial oil exposure in individuals who had participated in clean-up tasks following the wreck of the Prestige, three chromosomal bands (2q21, 3q27, 5q31) were found to be especially prone to breakage. A recent follow-up study, performed on the same individuals, revealed that the genotoxic damage had persisted six years after oil exposure.

OBJECTIVES

To determine whether there exist chromosome bands which are especially prone to breakages and to know if there is some correlation with those detected in the previous study. In addition, to investigate if the DNA repair problems detected previously persist in the present study.

DESIGN

Follow-up study performed six years after the Prestige oil spill.

SETTING

Fishermen cooperatives in coastal villages.

PARTICIPANTS

Fishermen highly exposed to oil spill who participated in previous genotoxic study six years after the oil.

MEASUREMENTS

Chromosome damage in peripheral lymphocytes. For accurate identification of the breakpoints involved in chromosome damage of circulating lymphocytes, a sequential stain/G-banding technique was employed. To determine the most break-prone chromosome bands, two statistical methods, the Fragile Site Multinomial and the chi-square tests (where the bands were corrected by their length) were used. To compare the chromosome lesions, structural chromosome alterations and gaps/breaks between two groups of individuals we used the GEE test which takes into account a possible within-individual correlation. Dysfunctions in DNA repair mechanisms, expressed as chromosome damage, were assessed in cultures with aphidicolin by the GEE test.

RESULTS

Cytogenetic analyses were performed in 47 exposed individuals. A total of 251 breakpoints in exposed individuals) were identified, showing a non-uniform distribution in the human ideogram. Ten chromosome bands were found to be especially prone to breakage through both statistical methods. By comparing these bands with those observed in certain exposed individuals who had already participated the previous study, it was found in both studies that four bands (2q21, 3q27, 5q31 and 17p11.2) are particularly sensitive to breakage. Additionally, the dysfunction in DNA repair mechanisms was not significantly higher in oil-exposed individuals than in non-exposed individuals.

LIMITATIONS

The sample size and the possibility of some kind of selection bias should be considered. Genotoxic results cannot be extrapolated to the high number of individuals who participated occasionally in clean-up tasks.

CONCLUSION

Our findings show the existence of at least four target bands (2q21, 3q27, 5q31 and 17p11.2) with a greater propensity to break over time after an acute exposure to oil. The breaks in these bands, which are commonly involved in hematological cancer, may explain the increase of cancer risk reported in chronically benzene-exposed individuals. In addition, a more efficiency of the DNA repair mechanisms has been detected six years after in fishermen who were highly exposed to the oil spill. To date, only this study, performed by our group on the previous and present genotoxic effects, has analyzed the chromosomal regions affected by breakage after an acute oil exposure.

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.

The impact of oil spill to lung health--Insights from an RNA-seq study of human airway epithelial cells

The Deepwater Horizon oil spill (BP oil spill) in the Gulf of Mexico was a unique disaster event, where a huge amount of oil spilled from the sea bed and a large volume of dispersants were applied to clean the spill. The operation lasted for almost 3 months and involved >50,000 workers. The potential health hazards to these workers may be significant as previous research suggested an association of persistent respiratory symptoms with exposure to oil and oil dispersants. To reveal the potential effects of oil and oil dispersants on the respiratory system at the molecular level, we evaluated the transcriptomic profile of human airway epithelial cells grown under treatment of crude oil, the dispersants Corexit 9500 and Corexit 9527, and oil-dispersant mixtures. We identified a very strong effect of Corexit 9500 treatment, with 84 genes (response genes) differentially expressed in treatment vs. control samples. We discovered an interactive effect of oil-dispersant mixtures; while no response gene was found for Corexit 9527 treatment alone, cells treated with Corexit 9527+oil mixture showed an increased number of response genes (46 response genes), suggesting a synergic effect of 9527 with oil on airway epithelial cells. Through GO (gene ontology) functional term and pathway-based analysis, we identified upregulation of gene sets involved in angiogenesis and immune responses and downregulation of gene sets involved in cell junctions and steroid synthesis as the prevailing transcriptomic signatures in the cells treated with Corexit 9500, oil, or Corexit 9500+oil mixture. Interestingly, these key molecular signatures coincide with important pathological features observed in common lung diseases, such as asthma, cystic fibrosis and chronic obstructive pulmonary disease. Our study provides mechanistic insights into the detrimental effects of oil and oil dispersants to the respiratory system and suggests significant health impacts of the recent BP oil spill to those people involved in the cleaning operation.

Follow-Up Genotoxic Study: Chromosome Damage Two and Six Years after Exposure to the Prestige Oil Spill

BACKGROUND

The north-west coast of Spain was heavily contaminated by the Prestige oil spill, in 2002. Individuals who participated in the clean-up tasks showed increased chromosome damage two years after exposure. Long-term clinical implications of chromosome damage are still unknown.

OBJECTIVE

To realize a follow-up genotoxic study to detect whether the chromosome damage persisted six years after exposure to the oil.

DESIGN

Follow-up study.

SETTING

Fishermen cooperatives in coastal villages.

PARTICIPANTS

Local fishermen who were highly exposed (n = 52) and non-exposed (n = 23) to oil seven years after the spill.

MEASUREMENTS

Chromosome damage in circulating lymphocytes.

RESULTS

Chromosome damage in exposed individuals persists six years after oil exposure, with a similar incidence than those previously detected four years before. A surprising increase in chromosome damage in non-exposed individual was found six years after Prestige spill vs. those detected two years after the exposure.

LIMITATIONS

The sample size and the possibility of some kind of selection bias should be considered. Genotoxic results cannot be extrapolated to the approximately 300,000 individuals who participated occasionally in clean-up tasks.

CONCLUSION

The persistence of chromosome damage detected in exposed individuals six years after oil exposure seems to indicate that the cells of the bone marrow are affected. A surprising increase in chromosome damage in non-exposed individuals detected in the follow-up study suggests an indirect exposition of these individuals to some oil compounds or to other toxic agents during the last four years. More long-term studies are needed to confirm the presence of chromosome damage in exposed and non-exposed fishermen due to the association between increased chromosomal damage and increased risk of cancer. Understanding and detecting chromosome damage is important for detecting cancer in its early stages. The present work is the first follow-up cytogenetic study carried out in lymphocytes to determine genotoxic damage evolution between two and six years after oil exposure in same individuals.

Evaluating the stress response as a bioindicator of sub-lethal effects of crude oil exposure in wild house sparrows (Passer domesticus)

Petroleum can disrupt endocrine function in humans and wildlife, and interacts in particularly complex ways with the hypothalamus-pituitary-adrenal (HPA) axis, responsible for the release of the stress hormones corticosterone and cortisol (hereafter CORT). Ingested petroleum can act in an additive fashion with other stressors to cause increased mortality, but it is not clear exactly why--does petroleum disrupt feedback mechanisms, stress hormone production, or both? This laboratory study aimed to quantify the effects of ingested Gulf of Mexico crude oil on the physiological stress response of house sparrows (Passer domesticus). We examined baseline and stress-induced CORT, negative feedback, and adrenal sensitivity in house sparrows given a 1% oil or control diet (n = 12 in each group). We found that four weeks on a 1% oil diet did not alter baseline CORT titers or efficacy of negative feedback, but significantly reduced sparrows' ability to secrete CORT in response to a standardized stressor and adrenocorticotropin hormone injection, suggesting that oil damages the steroid-synthesizing cells of the adrenal. In another group of animals on the same 1% oil (n = 9) or control diets (n = 8), we examined concentrations of eight different blood chemistry parameters, and CORT in feathers grown before and during the feeding experiments as other potential biomarkers of oil exposure. None of the blood chemistry parameters differed between birds on the oil and control diets after two or four weeks of feeding, nor did feather CORT differ between the two groups. Overall, this study suggests that the response of CORT to stressors, but not baseline HPA function, may be a particularly sensitive bioindicator of sub-lethal chronic effects of crude oil exposure.

Follow-up study of genotoxic effects in individuals exposed to oil from the tanker Prestige, seven years after the accident

The accident with the oil tanker Prestige in November 2002 resulted in a major spill of about 63,000 tons of heavy fuel oil. More than 300,000 people participated in the clean-up activities, which lasted for up to 10 months. Previous studies reported increases in genotoxicity endpoints in individuals exposed to Prestige oil, both at the moment of exposure [DNA breakage, micronuclei (MN), sister chromatid exchange] and two years later (chromosomal aberrations). In this work we carried out for the first time the follow-up of genotoxic effects in subjects exposed to an oil spill seven years after the exposure. The main objective was to determine the possible persistence of genotoxic damage in individuals exposed to Prestige oil seven years after the accident. The exposed group was composed of 54 residents of Galician villages in Spain that were heavily affected by the spill. This group was involved in clean-up labor for at least two months in the period November 2002-September 2003. They were compared with 50 matched controls. Primary DNA damage was evaluated by the comet assay, mutagenicity by the T-cell receptor (TCR) mutation assay, and MN frequency was determined both by the cytokinesis-block test and by flow cytometry. The results obtained showed no significant differences between the exposed and the controls in the comet assay, the TCR mutation assay and the cytokinesis-block MN test. An unexpected and significant decrease was observed in the exposed group for the results of the MN test evaluated by flow cytometry, probably influenced by modifying factors - other than age, sex and smoking - not considered in this study. Our results show no evidence of the persistence of genotoxic damage in individuals exposed to Prestige oil seven years later. Nevertheless, the need to plan biomonitoring studies on people participating in clean-up activities in case a new oil spill occurs should be established.

Chromosomal bands affected by acute oil exposure and DNA repair errors

BACKGROUND

In a previous study, we showed that individuals who had participated in oil clean-up tasks after the wreckage of the Prestige presented an increase of structural chromosomal alterations two years after the acute exposure had occurred. Other studies have also reported the presence of DNA damage during acute oil exposure, but little is known about the long term persistence of chromosomal alterations, which can be considered as a marker of cancer risk.

OBJECTIVES

We analyzed whether the breakpoints involved in chromosomal damage can help to assess the risk of cancer as well as to investigate their possible association with DNA repair efficiency.

METHODS

Cytogenetic analyses were carried out on the same individuals of our previous study and DNA repair errors were assessed in cultures with aphidicolin.

RESULTS

Three chromosomal bands, 2q21, 3q27 and 5q31, were most affected by acute oil exposure. The dysfunction in DNA repair mechanisms, expressed as chromosomal damage, was significantly higher in exposed-oil participants than in those not exposed (p= 0.016).

CONCLUSION

The present study shows that breaks in 2q21, 3q27 and 5q31 chromosomal bands, which are commonly involved in hematological cancer, could be considered useful genotoxic oil biomarkers. Moreover, breakages in these bands could induce chromosomal instability, which can explain the increased risk of cancer (leukemia and lymphomas) reported in chronically benzene-exposed individuals. In addition, it has been determined that the individuals who participated in clean-up of the oil spill presented an alteration of their DNA repair mechanisms two years after exposure.

Endocrine and immunological parameters in individuals involved in Prestige spill cleanup tasks seven years after the exposure

In November 2002 the oil tanker Prestige spilled 63,000tonnes of heavy oil off the northwest coast of Spain, impacting more than 1000km of coastline. A general concern led to a huge mobilization of human and technical resources, and more than 300,000 people participated in cleanup activities, which lasted up to 10months. Some endocrine and immunological alterations were reported in Prestige oil exposed subjects for several months. Therefore, the objective of this study was to evaluate if these alterations are still present seven years after the exposure. Fifty-four individuals exposed for at least 2months were compared to 50 matched referents. Prolactin and cortisol plasma concentrations, percentages of lymphocyte subsets (CD3(+), CD4(+), CD8(+), CD19(+), and CD56(+)16(+)), plasma levels of circulating cytokines (interleukin (IL) 2, IL4, IL6, IL10, tumour necrosis factor α, and interferon γ), and serum concentrations of neopterin, tryptophan and kynurenine were determined in peripheral blood samples. Results showed significant differences in exposed individuals vs. referents only in cortisol (increase), kynurenine and %CD16(+)56(+) lymphocytes (both decrease). Time of exposure to the oil or using protective clothes did not influence the results, but effect of using protective mask was observed on neopterin, %CD8(+), CD4(+)/CD8(+) ratio and IL4. Surveillance of the exposed individuals for early detection of possible health problems related to the endocrine or immunological systems is recommended.

Urinary metabolites before and after cleanup and subjective symptoms in volunteer participants in cleanup of the Hebei Spirit oil spill

BACKGROUND

On December 7th, 2007, the Hong Kong tanker Hebei Spirit (HS) (146,848 tons) was crushed by a crane ship near the shore of Taean, Korea. More than 12,547 kl of crude oil spilled into the sea and contaminated the western coastline of the Korean peninsula. For a period of six months after the accident, approximately 1,000,000 volunteers participated in the cleanup. Our goal in this study was to examine the exposure status and acute health effects on volunteers that participated in the oil spill cleanup.

METHODS

A survey questionnaire was filled out by 565 volunteers, requesting information regarding physical symptoms. Out of the total number of participants, urine samples from 105 university student volunteers were collected before and after the cleanup work, and metabolite levels of volatile organic compounds and polycyclic aromatic hydrocarbons were analyzed.

RESULTS

Volunteers that participated for longer cleanup work reported an increase in physical symptoms including visual disturbance, nasal and bronchus irritation, headaches, heart palpitations, fatigue and fever, memory and cognitive disturbance, and abdominal pain. The levels of t,t-muconic acid, mandelic acid, and 1-hydroxypyrene were significantly higher in samples after cleanup than those measured before participation (p<0.05). Other than the associated risk of dermal irritation with the difference in the t,t-muconic acid level between the post- to pre-cleanup levels, no other physical symptoms demonstrated a significant association with changes observed in the levels of urinary metabolites.

CONCLUSIONS

Based on the significant increase of subjective symptoms in volunteers participating in the study, monitoring of the long term health effects, focusing on those with longer exposure, is warranted.

The duration of acute health problems in people involved with the cleanup operation of the Hebei Spirit oil spill

The authors investigated the duration of health problems of people involved with cleanup efforts for the Hebei Spirit oil spill, which occurred in December 2007 in Taean County, South Korea. The study identified risk factors correlated with the continuation of symptoms. Approximately one year after the accident, 442 people who had participated in the cleanup operation were examined. Data regarding demographic information, risk factors, and the continuation and duration of any symptoms were obtained. Eye symptoms (9.7 months), headaches (8.4 months), skin symptoms (8.3 months), and neurovestibular symptoms (6.9 months) had a relatively longer duration than did back pain (1.8 months) or respiratory symptoms (2.1 months). In particular, the remission of headaches had a negative correlation with female gender (HR 0.57, 0.34-0.95, 95% CI), and remission of eye symptoms had a negative correlation with the total hours of daily participation in the cleanup operation (HR 0.24, 0.06-0.95, 95% CI).

Cytogenetic methods in human biomonitoring: principles and uses

Cellular phenotypes can be applied as biomarkers to differentiate normal from abnormal biological -conditions. Several cytogenetic methods have been developed and allow the accurate detection of such phenotypic changes.Based on their mechanisms of formation, cellular phenotypes may be used either as biomarkers of exposure or as biomarkers of effect. Therefore, it is important that cytogenetic methods implemented in human biomonitoring should be based on a good knowledge of these mechanisms.In this chapter, we aim to review the mechanistic basis, the methodology, and the use in human biomonitoring studies of four major cytogenetic endpoints: sister chromatid exchanges (SCEs), high frequency cells (HFCs), chromosomal aberrations (CAs), and micronuclei (MN). In addition, an overview of potential confounding factors on the induction of these cytogenetic makers is presented. Furthermore, the combination of cytogenetics with molecular methods, which allows chromosome and gene identification on metaphase as well as in interphase cells with high resolution, is discussed. Finally, practical recommendations for an efficient application of these cytogenetic assays and a correct interpretation of the results on the basis of cellular phenotype(s) assessment in human biomonitoring are highlighted.

Application of biological monitoring for exposure assessment following chemical incidents: a procedure for decision making

Determination of the level of exposure during and after a chemical incident is crucial for the assessment of public health risks and for appropriate medical treatment, as well as for subsequent health studies that may be part of disaster management. Immediately after such an incident, there is usually no opportunity to collect reliable quantitative information on personal exposures and environmental concentrations may fall below detectable levels shortly after the incident has passed. However, many substances persist longer in biological tissues and thus biological monitoring strategies may have the potential to support exposure assessment, as part of health studies, even after the acute phase of a chemical incident is over. Reported successful applications involve very persistent chemical substances such as protein adducts and include those rare cases in which biological tissues were collected within a few hours after an incident. The persistence of a biomarker in biological tissues, the mechanism of toxicity, and the sensitivity of the analysis of a biomarker were identified as the key parameters to support a decision on the feasibility and usefulness of biological monitoring to be applied after an incident involving the release of hazardous chemicals. These input parameters could be retrieved from published methods on applications of biomarkers. Methods for rapid decision making on the usefulness and feasibility of using biological monitoring are needed. In this contribution, a stepwise procedure for taking such a decision is proposed. The persistence of a biomarker in biological tissues, the mechanism of toxicity, and the sensitivity of the analysis of a biomarker were identified as the key parameters to support such a decision. The procedure proposed for decision making is illustrated by case studies based on two documented chemical incidents in the Netherlands.

Hebei spirit oil spill exposure and subjective symptoms in residents participating in clean-up activities

OBJECTIVES

This study was conducted to examine the relationship between crude oil exposure and physical symptoms among residents participating in clean-up work associated with the Hebei Spirit oil spill, 2007 in Korea.

METHODS

A total of 288 residents responded to a questionnaire regarding subjective physical symptoms, sociodemographic characteristics and clean-up activities that occurred between two and eight weeks after the accident. Additionally, the urine of 154 of the respondents was analyzed for metabolites of volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs) and heavy metals. To compare the urinary levels of exposure biomarkers, the urine of 39 inland residents who were not directly exposed to the oil spill were analyzed.

RESULTS

Residents exposed to oil remnants through clean-up work showed associations between physical symptoms and the exposure levels defined in various ways, including days of work, degree of skin contamination, and levels of some urinary exposure biomarkers of VOCs, metabolites and metals, although no major abnormalities in urinary exposure biomarkers were observed.

CONCLUSIONS

This study provides evidence of a relationship between crude oil exposure and acute human health effects and suggests the need for follow-up to evaluate the exposure status and long-term health effects of clean-up participants.

Review on the effects of exposure to spilled oils on human health

Harmful effects of oil spills on diverse flora and fauna species have been extensively studied. Nevertheless, only a few studies have been compiled in the literature dealing with the repercussions of oil exposure on human health; most of them have focused on acute effects and psychological symptoms. The objective of this work was to gather all these studies and to analyze the possible consequences of this kind of complex exposure in the different aspects of human health. Studies found on this topic were related to the disasters of the Exxon Valdez, Braer, Sea Empress, Nakhodka, Erika, Prestige and Tasman Spirit oil tankers. The majority of them were cross-sectional; many did not include control groups. Acute effects were evaluated taking into account vegetative-nervous symptoms, skin and mucous irritations, and also psychological effects. Genotoxic damage and endocrine alterations were assessed only in individuals exposed to oil from Prestige. The results of the reviewed articles clearly support the need for biomonitoring human populations exposed to spilled oils, especially those individuals involved in the cleanup, in order to evaluate not only the possible immediate consequences for their health but also the medium- and long-term effects, and the effectiveness of the protective devices used.

Biomonitoring of human exposure to prestige oil: effects on DNA and endocrine parameters

Since 1960, about 400 tankers spilled more than 377765 tons of oil, with the Prestige accident (Galician coast, NW Spain, November 2002) the most recent. Taking into account the consistent large number of individuals exposed to oil that exists all over the world, it seems surprising the absence in the literature of studies focused on the chronic effects of this exposure on human health. In this work we evaluated the level of DNA damage by means of comet assay, and the potential endocrine alterations (prolactin and cortisol) caused by Prestige oil exposure in a population of 180 individuals, classified in 3 groups according to the tasks performed, and 60 controls. Heavy metals in blood were determined as exposure biomarkers, obtaining significant increases of aluminum, nickel and lead in the exposed groups as compared to controls. Higher levels of genetic damage and endocrine alterations were also observed in the exposed population. DNA damage levels were influenced by age, sex, and the use of protective clothes, and prolactin concentrations by the last two factors. Surprisingly, the use of mask did not seem to protect individuals from genetic or endocrine alterations. Moreover, polymorphisms in genes encoding for the main enzymes involved in the metabolism of oil components were analyzed as susceptibility biomarkers. CYP1A1-3'UTR and EPHX1 codons 113 and 139 variant alleles were related to higher damage levels, while lower DNA damage was observed in GSTM1 and GSTT1 null individuals.

Challenges of exposure assessment for health studies in the aftermath of chemical incidents and disasters

Exposure assessment during and after acute chemical incidents and disasters is essential for health studies that may follow. During chemical incidents, the focus usually lies on risk assessment and afterward attention shifts toward possible (long-term) health effects. This may lead to insufficient available data on exposure to study the association between exposure and health outcome, and collection of additional exposure data is often required. Literature on health studies conducted after several chemical incidents was reviewed to obtain better insight on the needs of health studies. Four different types of scenarios were distinguished based on when exposure data were collected and the exposure data used for health studies. These four scenarios gave insight on exposure data needed for conclusive health studies and when different methods of exposure data collection should be used. Literature indicated that adequate and rapid exposure assessment during chemical incidents is vital for health studies, because data that are not collected during or directly after an incident may be irretrievably lost. Poor exposure assessment is not always the only problem in health studies. Problems in health studies including poor exposure assessment may be prevented when the general design and needs of health studies are taken into account when designing contingency plans. Together with measures that will help facilitate funding, design, and coordination of health studies, disaster management programs should, among others, prepare for methods that lead to a swift identification of released substances, determination of concentrations and dispersion of released substances, designing basic questionnaire outlines, and rapid evaluation of the usefulness and necessity of employing biological sampling.

Cytogenetic effects induced by Prestige oil on human populations: the role of polymorphisms in genes involved in metabolism and DNA repair

The spill from the oil tanker Prestige (NW Spain, November 2002) was perhaps the biggest ecological disaster that happened worldwide in the last decades. As a consequence of this catastrophe a general concern led to a huge mobilization of human and technical resources. Given that no information was reported in the scientific literature regarding to the chronic repercussions to human health of exposure to oil spills, a pilot study was performed by our group revealing some increased genotoxic effects in the subjects exposed to the oil during cleaning activities. Due to the seriousness of the results, we extended our study comprising a larger population and including an extensive evaluation of the main polymorphic sites in metabolizing and DNA-repair genes. General increases in micronucleus (MN) frequency and decreases in the proliferation index were observed in individuals with longer time of exposure. Age was a significant predictor of MN frequency. CYP1A1 3'-UTR, EPHX1 codons 113 and 139, GSTP1, GSTM1 and GSTT1 metabolic polymorphisms, and XRCC3 codon 241 and XPD codon 751 repair polymorphisms influenced cytogenetic damage levels. In view of these results, it seems essential to pay more attention to the chronic human health effects of exposure to oil and to focus new studies on such a relevant but overlooked public health field that involves a large number of people all over the world.

[Health effects of exposure to oil spills]

The sinking of the oil tanker Prestige off the coast of Galicia was not only the worst ecological disaster ever to affect Spain, it also led to thousands of people who participated in the cleanup of the contaminated areas being exposed to potentially dangerous toxic substances. As the airway is one of the principal routes of entry into the body of these toxic compounds, the possible effects of exposure to such spills is of particular interest and concern to respiratory specialists. The paucity of clinical information available on the subject was the motive for this paper, which reviews the scientific studies undertaken in the aftermath of other accidents involving oil tankers and concludes with a summary of the clinical and epidemiological data published to date on the Prestige oil spill.

Relationship between blood concentrations of heavy metals and cytogenetic and endocrine parameters among subjects involved in cleaning coastal areas affected by the 'Prestige' tanker oil spill

The sinking of the 'Prestige' oil tanker in front of the Galician coast (NW of Spain) in November 2002 offered a unique opportunity to analyze intermediate cytogenetic and endocrine effects among people exposed to the complex mixture of substances that oil constitutes, including several toxic heavy metals. In this work we evaluated the relationship between exposure to heavy metals (blood concentrations of aluminium, cadmium, nickel, lead and zinc) and genotoxic parameters (sister chromatid exchanges, micronucleus test and comet assay) or endocrine parameters (plasmatic concentrations of prolactin and cortisol) in subjects exposed to 'Prestige' oil during cleaning tasks developed after the spillage. Concentrations of lead were significantly related to the comet assay even after adjusting by age, sex and smoking. Cortisol concentrations were significantly influenced by aluminium, nickel (both, inversely) and cadmium (positively). Women had clearly higher concentrations of prolactin and cortisol, even when adjusting by age, smoking, cadmium, aluminium or nickel. Plasmatic cortisol was jointly influenced by gender, smoking and aluminium or nickel (all p<0.05). In women there was a strong relationship between concentrations of cadmium and prolactin (beta=0.37, p=0.031). When the effects of cadmium, aluminium and nickel on cortisol were simultaneously assessed, only the latter two metals remained statistically significant. Among parameters analysed, cortisol appeared to be the most sensitive to the effects of metal exposure. Plasma levels of cortisol deserve further evaluation as a potentially relevant biomarker to assess the effects of exposure to heavy metals.