Apr 15, 2014. Of ecotoxicology is to be able to predict the effects of pollution so that the most efficient and effective action to prevent or remediate any detrimental. Consequently, recent biomonitoring programs are now involving biomarkers. It results from free radical reactions in biological membranes, which are rich.
• 1.4k Downloads • Abstract It is widely recognized that marine mammals are exposed to a wide variety of pollutants, with a weight of evidence indicating impacts on their health. Since hundreds of new chemicals enter the global market every year, the methods, approaches and technologies used to characterize pollution levels or impacts are also in a constant state of flux. However, legal and ethical constraints often limit the type and extent of toxicological research being carried out in marine mammals. Nevertheless, new and emerging in vivo, in vitro as well as in silico research opportunities abound in the field of marine mammal toxicology. In the application of findings to population-, species-, or habitat-related risk assessments, the identification of causal relationships which inform source apportionment is important.
This, in turn, is informed by a comprehensive understanding of contaminant classes, profiles and fate over space and time. Such considerations figure prominently in the design and interpretation of marine mammal (eco)toxicology research. This mini-review attempts to follow the evolution behind marine mammal toxicology until now, highlight some of the research that has been done and suggest opportunities for future research.
This Special Issue will showcase new developments in marine mammal toxicology, approaches for exposure-effect research in risk assessment as well as future opportunities. Toxicology of marine mammals is a relatively small, but indispensable topic within the area of marine mammal sciences. It is a topic that has gained interest over the years due to the increased awareness of the toxic effects of pollutants in several organisms and the usually elevated levels of pollutants detected in marine mammal species (e.g. Tanabe et al.; Ross; Aguilar et al.; Houde et al.; Law et al.
Despite being in contaminated habitats, marine mammals get the bulk of their body burdens through their diet rather than directly from their environment (Gray ). It is because of their top position in the trophic chain, the biomagnification process and the persistence of several pollutants, that marine mammals can accumulate high levels of pollutants.
For biologists, marine mammal toxicology might be a highly theoretical and complex topic that sometimes seemingly abandons all connections with conservation and management. The ultimate goal in marine mammal toxicology, however, is to find minimally invasive and non-destructive tools or approaches that help to understand the causal link between pollution and its effects in marine mammals in order to (1) assess the past and current situation in terms of toxicology for marine mammals and to use that to (2) inform legislation for providing a healthier environment for these animals. This is a goal that will be valid for years and possibly decades to come and that fits seamlessly within any effort for conservation and management. Since hundreds of new chemicals enter the global market every year, the methods, approaches and technologies used to characterize pollution levels or impacts are generally also in a constant state of flux. This is also true for the methods, approaches and techniques used in marine mammal toxicology, despite the legal and ethical constraints when working with these animals. New and emerging in vivo, in vitro as well as in silico research opportunities abound in the field of marine mammal toxicology, both in exposure studies as well as in effect studies.
A comprehensive understanding of contaminant classes, profiles and fate over space and time can have a profound influence on the design and interpretation of marine mammal effect studies. This paper will provide a brief overview of past and current in vivo, in vitro and in silico research thereby stimulating future research opportunities in this topic (Fig. Fig. 1 Conceptual diagram of the different types of research that are underlying risk assessment in marine mammals. A represents the current situation in which results of in vitro research are difficult to implement in in silico models. B represents the ideal scenario in which all research types complement each other thereby facilitating (I) a thorough interpretation and understanding of current and past risks, as well as (II) an educated prediction and identification of risks in the future Overview of In Vivo, In Vitro and In Silico Research Directions in Marine Mammal Toxicology. Toxicological studies in marine mammals are hardly straightforward due to the protective guidelines that aim to protect marine mammals (inter)nationally.
Although there is no doubt about the necessity and usefulness of these conservation guidelines, they put constraints on the toxicological work that can be done for marine mammals. This explains the knowledge gaps that still exist, the careful interpretation of research outcomes as well as the methods and techniques that are employed in marine mammal toxicology. In this Special Issue, we have tried to showcase the current knowledge, novelties and opportunities in marine mammal toxicology. The field of marine mammal toxicology is broad and diverse, which is evidenced by the different topics, techniques, and species. Identix Biologon Software Download.
Out of 14 studies in total, seven are biomonitoring studies, four studies combine chemical analysis and health effects (in vitro) and three are modelling studies (in silico). All three modelling studies have studied POPs: PBDEs in the killer whale food chain (Alava et al. ), PCBs and OCPs in the beluga whale (Cadieux et al.
) and PCBs in polar bears (Pavlova et al. Brown and Ross ( ) have focussed on the transplacental transfer of PCBs, PBDEs and OCPs in ringed seal mother-fetus pairs. ( ) and McHuron et al. ( ) have investigated the influence of biological factors (e.g. Age, gender, location) on the bioaccumulation of total mercury (THg) in hair/whiskers (Noel et al. ) and hair/blood (McHuron et al.
) of harbour seals and California sea lions, respectively. Peterson et al. ( ) have studied the relationship between THg levels in blood and hair in four different pinniped species.
Kakuschke and Griesel as well as Hansen et al. ( ) have analysed a battery of trace elements in marine mammals: in blood of harbour seals (Kakuschke and Griesel ) and in liver of 16 cetacean Species (Hansen et al. Furthermore, although it is often very difficult to obtain feces samples of cetaceans, Lundin et al.
( ) have managed to obtain and analyse feces samples of killer whales. Results of these biomonitoring studies can be compared to toxicity thresholds or previously reported effect levels, however, they do not have the same direct correlations between exposure and effect as the effect-studies in this Special Issue. Reiner et al. ( ), Lehnert et al.
( ), Bogomolni et al. ( ) and Dupont et al. ( ) have investigated the correlations between different toxic endpoints and the levels of POPs (Reiner et al.; Lehnert et al.; Bogomolni et al. ) or trace elements (Lehnert et al.; Dupont et al.
) in tissues of pinnipeds. These endpoints range from vitamin A and E measurements (Reiner et al. ) to cellular/molecular biomarkers and haematology (Lehnert et al.; Bogomolni et al.; Dupont et al. In addition to this, Bogomolni et al. ( ) have ventured a step further and have investigated whether exposure increased the likelihood to Phocine Distemper Virus. The discipline of toxicology in marine mammals has come a long way, for in vivo, in vitro as well as in silico research, but we are not quite there yet.
Knowing that the highest levels of pollutants were detected in killer whales and polar bears, that pollutants are causing immunotoxicity in several marine mammal species or that the elimination half-life of pollutants can be longer than the entire lifetime of a marine mammal, is obviously very useful. All those findings, and many more, have prompted toxicologists for decades to continue investigating marine mammals and to be increasingly creative in solving important questions. Heena Mp4 Songs Free Download. However, for a streamlined approach to conserve and manage marine mammal populations, studies have to be combined and results need to complement each other as has been proposed earlier by Ross ( ).
It is the interface between in vitro, in vivo and in silico research that is of great importance for future conservation and management purposes (Fig. Unfortunately, it is also that interface that is the most challenging, especially in an ever-changing environment. Exposure has changed over time and new compounds are becoming more and more important, even if ‘old’ pollutants still have an important role in marine mammal toxicology. Future research should take this into account and also focus on more novel and emerging compounds. Pollution differs spatially, meaning that more site-specific knowledge about dietary and ecological factors should be integrated in toxicological research to thoroughly understand the degree of exposure and impact on marine mammal populations.
Finally, new biomarkers need to be developed and implemented in addition to the more ‘traditional’ ones parallel with the analysis of novel and emerging compounds in order to streamline conservation efforts for the next decades.
Ecotoxicology Essentials: Environmental Contaminants and Their Biological Effects on Animals and Plants provides a fundamental understanding of this area for students and professionals in ecotoxicology, ecology, conservation, chemistry, public health, wildlife management, fisheries, and many other disciplines. Although new chemicals and potential problems are developed every year, a basic education is essential to address these new challenges, and this work gives such training.
Written with the regulatory framework in mind, the material guides readers on modelling, how to conduct assessments, and human and wildlife risk, focusing on effects on animals rather than transport of chemicals. Simple discussions of chemistry are complemented by coverage on the behavior of the animal, dynamics of the ecosystem, real-life situations like drought, and predators in the system – i.e., the natural system versus the lab setting. The book’s first section contains chapters on the principles of contaminant toxicology including a brief history of the science of ecotoxicology, basic principles of the science, testing methods, and ways of determining if animals have been exposed to either acute or chronic concentrations of contaminants. The second section deals with the primary classes of contaminants including their chemical characteristics, sources, uses, and effects on organisms. The third section focuses on more complex issues such as the regulation of pollution, population and community effects, risk assessment and modelling.
Key Features. • Section I: Basic Principles and Tools of Ecotoxicology • Chapter 1. An Introduction to Ecotoxicology • Abstract • Introduction • Characteristics of Chemicals That Affect Their Presence in the Natural Environment • Environmental Factors That Affect Contaminants • Basics of Assessing Toxicity • Study Questions • References • Chapter 2.
Basics of Toxicity Testing • Abstract • Introduction and Terms of the Tradecraft • Toxicity Testing: Historical Perspectives and Its Role as One Tool in the Ecotoxicology Toolbox • Opening the Ecotoxicology Toolbox: Common Elements of Toxicity Tests • Good Laboratory Practices • Focus—GLPs in Operation • Study Questions • References • Chapter 3. Bioindicators of Contaminant Exposure • Abstract • Introduction • Types of Bioindicators • Oxidative Stress • Plasma Enzymes • Other Blood Components • Evidence of Endocrine Disruption • Genetic and Chromosomal Damage • Histology • Genomics and Proteomics • Reproductive and Developmental Bioindicators • Study Questions • References • Section II: Chemistry and Effect of Major Families of Contaminants • Chapter 4. Organochlorine Pesticides • Abstract • Introduction • Sources and Use • General Chemical Characteristics • Examples of OCP Concentrations in Environmental Sources • Concentrations of OCPS in Animals • Biological Effects of Organochlorine Pesticides • Focus—Eggshell Thinning • Study Questions • References • Chapter 5. Current Use Pesticides • Abstract • Introduction • What Is a Current Use Pesticide? • Economics of Current Use Pesticides • A Brief History of Pesticide Use • Types of Pesticides • Other Inorganic and Biologic Pesticides • Focus—Examples of Pesticide Use • Study Questions • References • Chapter 6. Halogenated Aromatic Hydrocarbons • Abstract • Introduction • Introduction to Polychlorinated Biphenyls, Dioxins and Furans • Polybrominated Diphenyl Ethers and Polybrominated Biphenyls • Focus—In Situ Testing with Tree Swallows • Study Questions • References • Chapter 7. Polycyclic Aromatic Hydrocarbons • Abstract • Introduction • Chemical Characterististics of PAHs • Sources and Uses of PAHs • Persistence • Remediation of PAH-Contaminated Soils and Sediments • Environmental Concentrations • Some Examples of Biological Concentrations • Biological Effects of PAHs • Focus—Oil Spills and Wildlife • Study Questions • References • Chapter 8.
Metals • Abstract • Introduction • Sources of Metals in the Environment • Biological Effects of Metals • Characteristics of Selected Metals • Arsenic • Cadmium • Chromium • Copper • Lead • Mercury • Zinc • Focus—Avian Mortality Due to Lead Shot, Bullets, and Weights • Study Questions • References • Chapter 9. Other Contaminants • Abstract • Introduction • Plastics • Munitions • Acid Deposition • Pharmaceuticals • Nanoparticles • Study Questions • References • Section III: Identifying and Evaluating Large Scale Contaminant Hazards • Chapter 10.
Population Ecotoxicology: Exposure and Effects of Environmental Chemicals • Abstract • Introduction: Working Beyond Individual Organisms • Spatiotemporal Scales in Ecology and Ecotoxicology • Population Ecotoxicology • Life Table Analysis • Stochasticity and Uncertainty • Study Questions • References • Chapter 11. Community-Level and Ecosystem-Level Effects of Environmental Chemicals • Abstract • Introduction • Communities, Ecosystems, and Spatiotemporal Scales • Scientific Support for Community Effects From Contaminants • Biological Assessments • Communities and Ecosystems: Exposures and Effects • Study Questions • References • Chapter 12. Modeling in Ecotoxicology • Abstract • Introduction • Different Models, Different Realizations • Brief Explanations of Some Common Models in Ecotoxicology • Mathematical Tools and Ecotoxicology • Beyond Mathematical and Statistical Models: Uncertainty and Its Role in Modeling • Focus—PCBs and Crab Orchard Lake • Study Questions • References • Chapter 13. Chemical Stressors and Ecological Risk • Abstract • Introduction • Terms of the Tradecraft • Historical Perspectives on Chemical Stressors and Ecological Risks • Generalized Process for Evaluating Environmental Risks • Exposure Models and Food-Chain Analysis for Birds and Mammals • Estimating Risks Using Simple Ratio Estimators • Cause-and-Effect Relationships, Multiple Stressors, Uncertainty, and Risks • Cause-and-Effect Analysis • Study Questions • References • Chapter 14. Contaminant Considerations in Humans • Abstract • Introduction • How Are Humans Exposed to Contaminants? • Some Effects of Environmental Contaminants on Humans • Focus—Examples of Major Contaminant—Human Disasters • Study Questions • References • Chapter 15. Regulation of Environmental Chemicals and Damage Assessment • Abstract • Introduction • International Authorities • National Regulation of Contaminants • Study Questions • References • Chapter 16.
Wrap Up • Abstract • Introduction • Where Are We Now? • What Remains to be Done? • Needs and Suggestions for the Future of Risk Assessment and Regulation • Acknowledgments • References • Index.