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Letendre F, Ramos PAS, Cameron CB. The loss of crude oil droplets by filter feeders and the role of surfactants. MARINE POLLUTION BULLETIN 2023; 193:115174. [PMID: 37336047 DOI: 10.1016/j.marpolbul.2023.115174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 05/30/2023] [Accepted: 06/11/2023] [Indexed: 06/21/2023]
Abstract
Various methods of oil spill remediation exist, e.g., floating booms, controlled burning and the release of chemical surfactants. These surfactants facilitate the breakup of the slick into micron-sized droplets. Here, we studied the impact such a surfactant has on the size distribution of oil droplets in the water column and in the gut of the filter feeder Daphnia magna. We also studied the effect of surfactants on detachment conditions of chemically and mechanically dispersed oil (respectively MDO and CDO) droplets from capture fibers. Our results show that including solubilized dioctyl sulfosuccinate sodium salt in the mixing of the emulsion produces smaller droplets and a narrower size distribution in the water. In the gut, the size of ingested droplets does not change whether the oil is mixed mechanically or chemically. Also, surfactant coated droplets detach at a lower velocity than mechanically dispersed droplet because of their lower oil/water interfacial tension.
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Affiliation(s)
- Francis Letendre
- Département de sciences biologiques, Complexe des sciences, Université de Montréal, Montréal, Québec, Canada.
| | - Paloma Arena Serrano Ramos
- Département de sciences biologiques, Complexe des sciences, Université de Montréal, Montréal, Québec, Canada
| | - Christopher B Cameron
- Département de sciences biologiques, Complexe des sciences, Université de Montréal, Montréal, Québec, Canada
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2
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Wagner J, Akdere M, Gürbüz K, Beek L, Klopp K, Ditsche P, Mail M, Gries T, Barthlott W. Oil adsorbing and transporting surfaces: a simulative determination of parameters for bionic functional textiles. BIOINSPIRATION & BIOMIMETICS 2023; 18. [PMID: 36881911 DOI: 10.1088/1748-3190/acc224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 03/07/2023] [Indexed: 05/09/2023]
Abstract
Certain superhydrophobic plants, such asSalvinia molesta, are able to adsorb oil films from water surfaces and thus separate the oil from the water. There are first attempts to transfer this phenomenon to technical surfaces, but the functional principle and the influence of certain parameters are not yet fully understood. The aim of this work is to understand the interaction behavior between biological surfaces and oil, and to define design parameters for transferring the biological model to a technical textile. This will reduce the development time of a biologically inspired textile. For this purpose, the biological surface is transferred into a 2D model and the horizontal oil transport is simulated in Ansys Fluent. From these simulations, the influence of contact angle, oil viscosity and fiber spacing/diameter ratio was quantified. The simulation results were verified with transport tests on spacer fabrics and 3D prints. The values obtained serve as a starting point for the development of a bio-inspired textile for the removal of oil spills on water surfaces. Such a bio-inspired textile provides the basis for a novel method of oil-water separation that does not require the use of chemicals or energy. As a result, it offers great added value compared to existing methods.
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Affiliation(s)
- Jan Wagner
- Institut fuer Textiltechnik, RWTH Aachen University, Otto-Blumenthal-Strasse 1, 52074 Aachen, Germany
| | - Musa Akdere
- Institut fuer Textiltechnik, RWTH Aachen University, Otto-Blumenthal-Strasse 1, 52074 Aachen, Germany
| | - Kevser Gürbüz
- Institut fuer Textiltechnik, RWTH Aachen University, Otto-Blumenthal-Strasse 1, 52074 Aachen, Germany
| | - Leonie Beek
- Institut fuer Textiltechnik, RWTH Aachen University, Otto-Blumenthal-Strasse 1, 52074 Aachen, Germany
| | - Kai Klopp
- Heimbach GmbH, An Gut Nazareth 73, 52353 Dueren, Germany
| | - Petra Ditsche
- Nees Institute for Biodiversity of Plants, University of Bonn, Venusbergweg 22, 53115 Bonn, Germany
| | - Matthias Mail
- Nees Institute for Biodiversity of Plants, University of Bonn, Venusbergweg 22, 53115 Bonn, Germany
- Karlsruhe Nano Micro Facility (KNMF), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Thomas Gries
- Institut fuer Textiltechnik, RWTH Aachen University, Otto-Blumenthal-Strasse 1, 52074 Aachen, Germany
| | - Wilhelm Barthlott
- Nees Institute for Biodiversity of Plants, University of Bonn, Venusbergweg 22, 53115 Bonn, Germany
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3
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Li Q, Zhao Q, Guo J, Li X, Song J. Transcriptomic Analysis of Diethylstilbestrol in Daphnia Magna: Energy Metabolism and Growth Inhibition. TOXICS 2023; 11:197. [PMID: 36851071 PMCID: PMC9962875 DOI: 10.3390/toxics11020197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 02/01/2023] [Accepted: 02/09/2023] [Indexed: 06/18/2023]
Abstract
With the widespread use of diethylstilbestrol (DES), it has become a common contaminant in the aquatic environment. It is toxic to a wide range of aquatic organisms, disrupting the water flea growth and further interfering with several ecosystem services. Nevertheless, the molecular mechanism of DES in water fleas is still unexplicit. In this study, the 21-day chronic test showed that a negative effect of growth and reproduction can be observed with DES exposure. Subsequently applied transcriptomic analysis illustrated the molecular mechanism in mode freshwater invertebrate Daphnia magna (D. magna) exposed to 2, 200, and 1000 μg·L-1 of DES for 9 days. Meanwhile, exposure to DES at 200 and 1000 μg·L-1 significantly restrains the growth (body length) and reproduction (first spawning time) of D. magna. Identified differentially expressed genes (DEGs) are majorly enriched relative to energy metabolism, lipid metabolism, the digestive system, transport and catabolism pathways which were remarkably changed. These repressed and up-regulated pathways, in relation to energy synthesis and metabolism, may be the reasons for the reduced body length and delayed first spawning time. Taken together, this study revealed that DES is a threat to D. magna in the aquatic environment and clarifies the molecular mechanism of the toxicity.
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Affiliation(s)
- Qi Li
- Correspondence: ; Tel.: +86-135-7200-0931
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4
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Techtmann SM, Santo Domingo J, Conmy R, Barron M. Impacts of dispersants on microbial communities and ecological systems. Appl Microbiol Biotechnol 2023; 107:1095-1106. [PMID: 36648524 PMCID: PMC10111227 DOI: 10.1007/s00253-022-12332-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 12/07/2022] [Accepted: 12/08/2022] [Indexed: 01/18/2023]
Abstract
Accidental oil spills can result in catastrophic ecological insults and therefore require rapid intervention to mitigate the potential impacts to aquatic ecosystems. One of the largest oil spills, known as the Deepwater Horizon oil spill, occurred in the Spring of 2010 near the coast of Louisiana (USA) due to an explosion during oil drilling activities. Millions of gallons of oil were released into the Gulf of Mexico, impacting thousands of ocean miles and coastal areas linked to the gulf. Among the actions taken during the remediation efforts was the unprecedented large use of Corexit dispersants, including at the subsurface to prevent oil from reaching the surface. While there is evidence that dispersants can accelerate the biodegradation of oil, reports on their potential toxicity to aquatic biota and to microbial functions have also been documented. In this review, we will examine the most recent literature on the impact of dispersants on microbial communities implicated in oil degradation and overall ecological networks. The primary focus will be on studies using Corexit but other dispersants will be discussed if data are available. We will share the literature gaps identified and discuss future work that is needed to reconcile some of the discrepancies found on the effectiveness of dispersants on oil degradation and their potential toxicity. KEY POINTS: • Chemical dispersants have been applied as a chemical response measure for oil spills. • The effects of chemical dispersants on microbial communities have been the subject of substantial research. • This work seeks to review recent work on the impact of chemical dispersants on oil biodegradation, microbial communities, and ecosystems.
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Affiliation(s)
- Stephen M Techtmann
- Department of Biological Sciences, Michigan Technological University, Houghton, MI, USA.
| | - Jorge Santo Domingo
- Office of Research and Development, U.S. Environmental Protection Agency, Cincinnati, OH, USA.
| | - Robyn Conmy
- Office of Research and Development, U.S. Environmental Protection Agency, Cincinnati, OH, USA
| | - Mace Barron
- Office of Research and Development, U.S. Environmental Protection Agency, Gulf Breeze, FL, USA
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5
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Bownik A. Physiological endpoints in daphnid acute toxicity tests. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 700:134400. [PMID: 31689654 DOI: 10.1016/j.scitotenv.2019.134400] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 08/16/2019] [Accepted: 09/09/2019] [Indexed: 06/10/2023]
Abstract
Daphnids are freshwater crustaceans used in toxicity tests. Although lethality and immobilisation are the most commonly used endpoints in those tests, more sensitive parameters are required for determination of sublethal acute effects of toxicants. The use of various physiological endpoints in daphnids is considered as a low-cost and simple alternative that meets the 3R's rule (Replacement, Reduction, Refinement) criteria. However, currently there is no review-based evaluation of their applicability in toxicity testing. This paper presents the results on the most commonly determined physiological parameters of Daphnia in ecotoxicological studies and human drug testing, such as feeding activity, thoracic limb movement, heart rate, cardiac area, respiratory activity, compound eye, mandible movements and post-abdominal claw contractions. Furthermore, their applicability as promising endpoints in the assessment of water quality or drug testing is discussed.
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Affiliation(s)
- Adam Bownik
- Department of Hydrobiology and Protection of Ecosystems, University of Life Sciences in Lublin, Dobrzańskiego 37, 20-262 Lublin, Poland.
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6
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Ferguson A, Solo-Gabriele H, Mena K. Assessment for oil spill chemicals: Current knowledge, data gaps, and uncertainties addressing human physical health risk. MARINE POLLUTION BULLETIN 2020; 150:110746. [PMID: 31910518 DOI: 10.1016/j.marpolbul.2019.110746] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 10/29/2019] [Accepted: 11/15/2019] [Indexed: 06/10/2023]
Abstract
Limited models are available to estimate human physical health risks (e.g., probability of outcomes such as lung disease, cancer, skin disease) from exposure to chemicals resulting from oil spills that may occur offshore and later impact coastline spills. An approach is presented to assess physical health risks from oil spills that involves establishing a platform capable of assessing aggregate health risk (via inhalation, ingestion, and dermal exposure routes). Gaps include the need to develop models reflecting oil spill concentration distributions given the influence from environmental, physical, biological and chemical factors. Human activities need to be quantified for different populations including emergency response workers, fishermen, shellfish consumers, and children who play at beaches that may be impacted by oil spills. Work is also needed in developing comprehensive toxicological profiles for the majority of chemicals - including dispersants found in oil spills - and to estimate toxicity from mixtures.
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Affiliation(s)
- Alesia Ferguson
- University of North Carolina Agriculatural and Technical State University (NCAT), Built Environment Department, Greensboro, NC 27411, United States.
| | - Helena Solo-Gabriele
- University of Miami, Department of Civil, Architectural, and Environmental Engineering, Coral Gables, FL 33146, United States.
| | - Kristina Mena
- University of Texas - Houston, School of Public Health, Houston, TX 77030.
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7
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Eklund RL, Knapp LC, Sandifer PA, Colwell RC. Oil Spills and Human Health: Contributions of the Gulf of Mexico Research Initiative. GEOHEALTH 2019; 3:391-406. [PMID: 32159026 PMCID: PMC7038885 DOI: 10.1029/2019gh000217] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 10/04/2019] [Accepted: 10/12/2019] [Indexed: 05/23/2023]
Abstract
The Gulf of Mexico Research Initiative (GoMRI) was established in 2010 with $500 million in funding provided by British Petroleum over a 10-year period to support research on the impacts of the Deepwater Horizon oil spill and recovery. Contributions of the GoMRI program to date focused on human health are presented in more than 32 peer-reviewed papers published between 2011 and May 2019. Primary findings from review of these papers are (i) the large quantity of dispersants used in the oil cleanup have been associated with human health concerns, including through obesogenicity, toxicity, and illnesses from aerosolization of the agents; (ii) oil contamination has been associated with potential for increases in harmful algal blooms and numbers of pathogenic Vibrio bacteria in oil-impacted waters; and (iii) members of Gulf communities who are heavily reliant upon natural resources for their livelihoods were found to be vulnerable to high levels of life disruptions and institutional distrust. Positive correlations include a finding that a high level of community attachment was beneficial for recovery. Actions taken to improve disaster response and reduce stress-associated health effects could lessen negative impacts of similar disasters in the future. Furthermore, GoMRI has supported annual conferences beginning in 2013 at which informative human health-related presentations have been made. Based on this review, it is recommended that the Oil Pollution Act of 1990 be updated to include enhanced funding for oil spill impacts to human health.
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Affiliation(s)
- Ruth L. Eklund
- Masters in Environmental and Sustainability Studies ProgramCollege of CharlestonCharlestonSCUSA
| | - Landon C. Knapp
- Center for Coastal Environmental and Human HealthCollege of CharlestonCharlestonSCUSA
| | - Paul A. Sandifer
- Center for Coastal Environmental and Human HealthCollege of CharlestonCharlestonSCUSA
| | - Rita C. Colwell
- University of MarylandMDUSA
- School of Public HealthJohns Hopkins UniversityBaltimoreMDUSA
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8
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McNabb NA, Bernhard MC, Brunell A, Lowers RH, Katsu Y, Spyropoulos DD, Kohno S. Oil dispersant Corexit 9500 is weakly estrogenic, but does not skew the sex ratio in Alligator mississippiensis. J Appl Toxicol 2019; 40:245-256. [PMID: 31486105 DOI: 10.1002/jat.3900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 08/06/2019] [Accepted: 08/06/2019] [Indexed: 11/06/2022]
Abstract
During the Deepwater Horizon oil spill, vast quantities of a chemical dispersant Corexit 9500 were applied in remediation efforts. In addition to the acute toxicity, it is essential to evaluate Corexit further with a broader scope of long-term sublethal endocrine endpoints. The American alligator (Alligator mississippiensis) is an excellent organism for such an endeavor. It exhibits temperature-dependent sex determination, in which egg incubation temperatures during a thermosensitive period (TSP) in embryonic development determine the sex of embryos. Estrogen signals play a critical role in this process. For example, a single exposure to exogenous estrogen during the TSP overrides the effects of temperature and leads to skewed sex ratios. At a concentration of 100 ppm, Corexit significantly induced transcriptional activity of both alligator nuclear estrogen receptors 1 and 2 in vitro in reporter gene assays. To investigate the estrogenic effects of Corexit on gonadal development, alligator eggs were exposed to Corexit at environmentally relevant concentrations (0.25, 2.5 and 25 ppm) before the TSP in ovo. Exposure to Corexit at 0.25 and 25 ppm significantly delayed hatching and growth. Corexit exposure at any treatment level did not affect sex ratios or testicular mRNA abundance as measured at 1-week post-hatching, suggesting that the combination of Corexit components did not synergize enough to induce ovarian development in ovo. These results point to a need for further investigations on individual and combined components of Corexit to understand better their long-term effects on the development and reproductive health of alligators and other coastal aquatic wildlife.
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Affiliation(s)
- Nicole A McNabb
- Graduate Program in Marine Biology, The University of Charleston, South Carolina at the College of Charleston, Charleston, South Carolina.,Hollings Marine Laboratory, Charleston, South Carolina.,Department of Environmental Toxicology, University of California, Davis, California
| | - Melissa C Bernhard
- Graduate Program in Marine Biology, The University of Charleston, South Carolina at the College of Charleston, Charleston, South Carolina.,Hollings Marine Laboratory, Charleston, South Carolina.,Mote Marine Laboratory and Aquarium, Sarasota, Florida
| | - Arnold Brunell
- Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, Eustis, Florida
| | | | | | - Demetri D Spyropoulos
- Hollings Marine Laboratory, Charleston, South Carolina.,Department of Pathology, Medical University of South Carolina, Charleston, South Carolina
| | - Satomi Kohno
- Hollings Marine Laboratory, Charleston, South Carolina.,Department of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina.,Aquatic Toxicology Laboratory, St. Cloud State University, St. Cloud, Minnesota
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9
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Gan T, Zhao N, Yin G, Chen M, Wang X, Liu J, Liu W. Optimal chlorophyll fluorescence parameter selection for rapid and sensitive detection of lead toxicity to marine microalgae Nitzschia closterium based on chlorophyll fluorescence technology. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2019; 197:111551. [DOI: 10.1016/j.jphotobiol.2019.111551] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 06/11/2019] [Accepted: 07/04/2019] [Indexed: 11/28/2022]
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10
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Tao R, Olivera-Irazabal M, Yu K. Effect of temperature and dispersant (COREXIT ® EC 9500A) on aerobic biodegradation of benzene in a coastal salt marsh sediment. CHEMOSPHERE 2018; 204:22-27. [PMID: 29649660 DOI: 10.1016/j.chemosphere.2018.04.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Revised: 04/03/2018] [Accepted: 04/04/2018] [Indexed: 06/08/2023]
Abstract
The coastal ecosystem in the northern Gulf of Mexico (GoM) has been seriously impacted by the 2010 BP oil spill. Two experiments were conducted to study the effect of temperature and addition of the dispersant on biodegradation of benzene, as a representative of petroleum hydrocarbon, in a coastal salt marsh sediment under aerobic conditions. The results show that benzene biodegradation was approximately 6 time faster under aerobic conditions (Eh > +300 mV) than under anaerobic iron-reduction conditions (+14 mV < Eh < +162 mV). Benzene biodegradation in response to temperature was in an order of 20 °C > 10 °C > 30 °C as expected in a saline environment. Application of the dispersant caused initial fluctuations of benzene vapor pressure during the incubation due to its hydrophobic and hydrophilic nature of the molecules. Presence of the dispersant shows an inhibitory effect on benzene biodegradation, and the inhibition increased with concentration of the dispersant. The Gulf coast sediment seems in a favorable scenario to recover from the BP oil spill with an average temperature around 20 °C in spring and fall season. Application of the dispersant may be necessary for the oil spill rescue operation, but its side effects may deserve further investigations.
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Affiliation(s)
- Rui Tao
- Department of Biological and Environmental Sciences, Troy University, Troy, AL 36082, USA
| | | | - Kewei Yu
- Department of Biological and Environmental Sciences, Troy University, Troy, AL 36082, USA; School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, Nanjing, 210044, China.
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11
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Salehi M, Rodriguez R, Boettcher A, Powers S, Geitner N, Ladner DA, Rikard S, Whelton AJ. Impact of dispersant on early life stages of the water flea
Daphnia magna
and the eastern oyster
Crassostrea virginica. J Appl Toxicol 2017; 37:1464-1470. [PMID: 28653411 DOI: 10.1002/jat.3494] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 05/05/2017] [Accepted: 05/15/2017] [Indexed: 12/24/2022]
Affiliation(s)
- Maryam Salehi
- Lyles School of Civil Engineering Purdue University IN 47907 USA
| | | | - Anne Boettcher
- Embry‐Riddle Aeronautical University Undergraduate Research Institute and Honors Program, Hazy Library Prescott AZ 86301 USA
| | - Sean Powers
- University of South Alabama Department of Marine Sciences AL 36688‐0002 USA
| | - Nick Geitner
- Center for the Environmental Implications of NanoTechnology Duke University Durham NC 27708‐0287 USA
| | - David A. Ladner
- Department of Environmental Engineering and Earth Sciences Clemson University Anderson SC 29625 USA
| | - Scott Rikard
- Auburn University, Auburn University Shellfish Laboratory AL 36528 USA
| | - Andrew J. Whelton
- Lyles School of Civil Engineering, Division of Environmental and Ecological Engineering Purdue University IN 47907 USA
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12
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Risk Assessment for Children Exposed to Beach Sands Impacted by Oil Spill Chemicals. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2016; 13:ijerph13090853. [PMID: 27618904 PMCID: PMC5036686 DOI: 10.3390/ijerph13090853] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 08/12/2016] [Accepted: 08/17/2016] [Indexed: 12/24/2022]
Abstract
Due to changes in the drilling industry, oil spills are impacting large expanses of coastlines, thereby increasing the potential for people to come in contact with oil spill chemicals. The objective of this manuscript was to evaluate the health risk to children who potentially contact beach sands impacted by oil spill chemicals from the Deepwater Horizon disaster. To identify chemicals of concern, the U.S. Environmental Protection Agency’s (EPA’s) monitoring data collected during and immediately after the spill were evaluated. This dataset was supplemented with measurements from beach sands and tar balls collected five years after the spill. Of interest is that metals in the sediments were observed at similar levels between the two sampling periods; some differences were observed for metals levels in tar balls. Although PAHs were not observed five years later, there is evidence of weathered-oil oxidative by-products. Comparing chemical concentration data to baseline soil risk levels, three metals (As, Ba, and V) and four PAHs (benzo[a]pyrene, benz[a]anthracene, benzo[b]fluoranthene, and dibenz[a,h]anthracene) were found to exceed guideline levels prompting a risk assessment. For acute or sub-chronic exposures, hazard quotients, computed by estimating average expected contact behavior, showed no adverse potential health effects. For cancer, computations using 95% upper confidence limits for contaminant concentrations showed extremely low increased risk in the 10−6 range for oral and dermal exposure from arsenic in sediments and from dermal exposure from benzo[a]pyrene and benz[a]anthracene in weathered oil. Overall, results suggest that health risks are extremely low, given the limitations of available data. Limitations of this study are associated with the lack of toxicological data for dispersants and oil-spill degradation products. We also recommend studies to collect quantitative information about children’s beach play habits, which are necessary to more accurately assess exposure scenarios and health risks.
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