2001 DSc. The University of Newcastle-upon-Tyne, Newcastle, England.
1973 Ph.D. The University of Newcastle upon Tyne (UK), Newcastle, England - Physiology
1969 B.S. The University of Newcastle upon Tyne (UK), Newcastle, England (Honours)
Interests
Ionic regulation in estuarine animals; bioaccumulation of trace metals; trace metal - electrolytic interactions in aquatic organisms; Risk assessments; effects of UV light on aquatic organisms; effects of natural product quinones on aquatic organisms; physical / chemical anti-fouling strategies.
Watercolor painting
Professional Experiences
1996-Present Professor, Chesapeake Biological Laboratory, Center for Environmental Science, University System of Maryland, Solomons, MD
1988-1996 Associate Professor, Chesapeake Biological Laboratory, Center for Environmental Science, University System of Maryland, Solomons, MD
1989-1990 Visiting Professor, University of Toronto, Institute for Environmental Studies, Toronto, CA
1979-1988 Assistant Professor, Chesapeake Biological Laboratory, Center for Environmental Science, University System of Maryland, Solomons, MD
1974-1978 Senior Demonstrator, The University of Newcastle-upon-Tyne (UK), Newcastle, England
1972-1973 Lecturer, Northern Counties College of Education (UK) [now Northumberland College of Arts and Technology], Northumberland, England
Recent Publications
Selected publication (last ten years)
Wright, D.A., J.D. Savitz, R. Dawson, J. Magee, and R.A. Smucker. 1995. Effect of diflubenzuron on the maturation and reproductive success of the copepod, Eurytemora affinis . Ecotoxicology 5: 47-58.
Wright, D.A. 1995. Trace metal and major ion interactions in aquatic animals. Mar. Poll. Bull. 31: 8-18.
Wright, D.A., E.M. Setzler-Hamilton, J.A. Magee, V.S. Kennedy, and S.P. McIninch. 1996. Effect of salinity and temperature on survival and development of young zebra (Dreissena polymorpha ) and quagga (D. bugensis ) mussels. Estuaries 19: 619-628.
Wright, D.A., and R.P. Mason. (2000). Biological and chemical influences on trace metal toxicity and bioaccumulation in the marine and estuarine environment. Int. J. Environ. Pollut. 13(1-6):226-248.
Wright, D.A. and P.M. Welbourn. 2002. Environmental Toxicology. 630 pp. Cambridge University Press.
Wright, D.A, R. Dawson, T.P. Mackey, H.G. Cutler and S.J. Cutler 2003. Full-Scale Shipboard Trials of Ballast Water Treatment Systems in Baltimore Harbor. Proceedings of 2nd Globallast International Ballast Water R&D Symposium at the International Maritime Organization. London, England. July 21-23, 2003. United Nations, IMO Globallast Program, London, England .
Cutler, S.J., H.G. Cutler, J. Glinski, D.A. Wright, R. Dawson and D. Lauren (2003). Use of Seakleenâ as a Treatment for Aquatic Pests in Ships’ Ballast Water. Proceedings of the 2nd International Ballast Water R&D Symposium at the International Maritime Organization. London, England. July 21-23, 2003. United Nations, IMO Globallast Program, London, England.
McGee, B.L., D.J. Fisher, D.A. Wright, L.T. Yonkos, G.P. Ziegler, S.D. Turley, J.D. Farrar, D.W. Moore and T.S. Bridges. (2004). A field test and comparison of acute and chronic sediment toxicity tests with the estuarine amphipod Leptocheirus plumulosus in Chesapeake Bay, USA. Environ. Toxicol. and Chem., 23, 1751-1761.
Selected Invited Presentations(last two years)
May 2003. Aquatic Nuisance Species: A Global Health Problem. Presented at the Annual Conference of American Society of Sanitarians; Safety/Human Health Issues. May 27, 2003.
June 2003. Full-Scale Shipboard Trials of Ballast Water Treatment Systems in Baltimore Harbor. Presented at International Association for Great Lakes Research 46th Annual Conference on Great Lakes Research. June 22-26, 2003. Chicago, Illinois. (Senior author with R. Dawson).
July 2003. Full-Scale Shipboard Trials of Ballast Water Treatment Systems in Baltimore Harbor. Presented at the Summer Seminar Series. July 2003. Solomons, Maryland.
July 2003. Full-Scale Shipboard Trials of Ballast Water Treatment Systems in Baltimore Harbor. Presented at the 2nd International Ballast Water R&D Symposium at the International Maritime Organization. London, England. July 21-23, 2003. (Senior author with R. Dawson, T.P. Mackey, H.G. Cutler and S.J. Cutler).
July 2003. Seakleen® A potential product for Controlloing Aquatic Pests in Ships’ Ballast Water.Presented at the 2nd International Ballast Water R&D Symposium at the International Maritime Organization. London, England. July 21-23, 2003. (Co-author with S.J. Cutler, H.G. Cutler, J. Glinski, R. Dawson and D. Lauren).
August 2003. Ongoing development of two ballast water treatment technologies based on full-scale testing in Baltimore Harbor. T.P. Mackey, D.A. Wright and R. Dawson. Presented at the annual Marine Environmental Engineering Technology Symposium. In pursuit of Cleaner Seas. Arlington, VA.
March 2004. Development of a natural biocide for the control of non-indigenous species. Queens University, Kingston Ontario.
May 2004. Full-Scale Shipboard Testing of Ballast Water Treatment Systems. @nd International Conference and Exhibition on Ballast Water Management. Singapore. May 19th-20th.
September 2004. The Baltimore Harbor Ballast Water Treatment Technology Program. 13th Annual Non-indigenous Aquatic Nuisance Species Conference. Sligo, Ireland, September 20th-24th.
Teaching Activities
MEES 643. Introduction to Environmental Toxicology.
This course is a newly revamped introductory course in Environmental Toxicology designed for students new to the subject and students with some background in the discipline. For now no course prerequisites are being set, although it will be useful if students have at least some chemistry background. The course will serve as an introductory course for the Aquatic Toxicology course, and the two courses will be offered in alternating years (or perhaps alternating semesters depending on demand). The course is constructed around my textbook, Environmental Toxicology published in 2002 by Cambridge University Press. My co-author for this textbook is Professor P.M. Welbourn of Queens University, Ontario, Canada. The course, like the book takes a tiered approach to the subject. It begins with an introduction to dose-response and bioassays at the whole organism and molecular level, and moves on to a consideration of the many biotic and abiotic factors that influence toxicity. The first part of the course concludes with a synopsis of toxic endpoints at the population and community level. We then deal with specific classes of environmental chemicals and the toxic threat that they pose in the environment and move on to more complex issues associated with energy production, climate agriculture and paper manufacture.
The course concludes with lectures on risk assessment and regulatory toxicology.
MEES 643 Introduction to Environmental Toxicology. Course Summary
Lecture 1. Introduction, history of toxicology. Dose-response models.
Lecture 2. Bioassays and statistics associated with them.
Lecture 3. Application of bioassays.
Lecture 4. Route(s) of toxicant uptake. Concept of receptors.
Lecture 5. Toxicokinetics.
Lecture 6. Biotic factors affecting toxicity.
Lecture 7. Abiotic factors affecting toxicity
Lecture 8. Toxicity end-points at the population and community level.
MID-TERM TEST
Lecture 9. Toxicity at the molecular level
Lectures 10&11. Endocrine disruptors
Lecture 12. Case Study. The development of biocides and other technologies for the control of aquatic nuisance species.
Lectures 13-15. Toxicity of trace metals and metalloids.
Lecture 16. Pesticides.
Lecture 17. PCBs and hydrocarbons
Lecture 18. Metabolism of organic compounds
Lecture 19. Environmental effects of energy production.
Lecture 20. Nuclear Energy. Ionizing radiation
Lecture 21. Acid rain. Photochemical smog
Lecture 22. Global warming. Greenhouse effect
Lecture 23. Ozone, fluoride. Effects of pulp and paper manufacture.
Lecture 24. Agriculture.
Lecture 25. Case Study.
Lectures 26 & 27 Risk assessment.
Lecture 28. Regulatory Toxicology
Review ....
ADDITIONAL INFORMATION: Class-notes for all lectures (>100 pages of text plus dozens of figures and tables) with links to external references/sites will be entered on the web. Although the course is constructed in a similar manner to the textbook, the class-notes are not simply a regurgitation of the book and contain many independent references and examples. Grading will be based on a mid-term test (10 pts.), a final exam (20pts.) and an independent assignment (50pts.) that will be assigned early in the semester.
MEES 743/TOX 625. Aquatic Toxicology (taught mainly by Dr. Carys Mitchelmore)
This is an advanced course in mechanistic aspects of aquatic toxicology.
Research Projects
Baltimore Harbor Ballast Water Treatment (BWT) Program is now the largest of its kind in the U.S. and builds on 15 years continual financial support from the NOAA National Sea Grant Program. It represents a natural progression of a long term research initiative continually funded by NOAA since the 1980s. This program had its genesis in the concerns over the introduction (probably via ballast water) of the European zebra and quagga mussels into the Great Lakes system in the mid 1980s and their subsequent colonization of much of the western U.S. This prompted more general concerns over the economic and health effects of non-indigenous aquatic species world-wide.
It is now widely accepted that ballast water, used to maintain a ship’s trim and stability, is the principal vector for unintentional introduction of non-indigenous organisms into U.S. and international waters. The United Nations International Maritime Organization (IMO) estimates an annual economic cost of $123 billion worldwide, resulting from the inadvertent introduction of non-indigenous aquatic species, and this has gave rise in February 2004 to a major United Nations initiative to create major legislation in the form of a new international Convention.
The stated aims of the National Sea Grant BWT program were to establish the following progression:
Bench top research on treatment technologies ’ mesocosm scale experiments ’ shipboard scale demonstrations ’ effective commercial applications
The current shipboard demonstrations of emerging technologies now have as a major sponsor Maryland Port Administration, from whom we have so far received ca. $800,000 in the last four years.
In 1996 the NOAA non-indigenous species program evolved into the National Sea Grant Ballast Water Treatment Program in response to increasing legislative momentum from the U.N. and in the U.S. While early experiments at CBL in the mid 1990s included a variety of technologies including pulsed power and acoustics, the work became primarily focused on two lines of research; UV irradiation and natural product biocides. Initially the UV work was done with a high power (7KW) monochromatic excimer lamp developed by Triton Thalassic Technologies, CT, and provided key information on the killing power of UV applied to aquatic organisms other than bacteria. Experimental studies carried out in our laboratory at the Chesapeake Biological Laboratory (CBL) represented the first application of UV irradiation to the ballast water issue and provided the first demonstration that UV could be used to kill planktonic organisms. It was evident, however, that in order to kill plankton a dose as high as 200mW sec cm2 may be required. This is 6-7 times the dose that has been used for bactericidal treatment of domestic water supplies, and caused a major, multimillion dollar rethinking in the water treatment industry. This research provided the scaling parameters for the international design of UV-based BWT systems and illustrated a progression from bench-top studies to scaled-up systems for real world application. In doing so the research led to the development and design of practical, full-scale technology that has helped to solve a multibillion dollar international problem. Equipment manufactured for current testing and aboard commercial vessels was designed as a direct result of experiments carried out at CBL between 1995 and 2002.
Undoubtedly the most important line of research emanating from the project has been the use of quinones as broad spectrum biocides. To our knowledge this represents a new application for this group of compounds, many of which are natural plant products, and have enormous environmental potential. A major current research initiative is to determine the chemical half lives of many of these compounds. Their rapid degradation makes their environmental application particularly attractive.
Following a screening process involving over twenty compounds, the development of menadione (vitamin K) has now led to its adoption as a test product in Asia, Australia, Europe and Canada. This activity has generated a great deal of international interest in the project as a whole and led to the presentation of a total of ten invited papers in 2003 and 2004.
Following the 2001-2 shipboard trials we proposed to test the hypothesis that UV and biocide exposure used in combination would have at least an additive toxic effect on entrained biota. Preliminary data using cultured alga, Isochrysis galbana and bivalve (Crassostrea virginica) larvae from the UMCES Horn Point hatchery demonstrated that combined UV/menadione exposure was indeed additive (not synergistic). This creates the potential for very significant cost benefits of combination treatment technologies that could run into many millions of dollars over the next several years.
This project essentially represents an intersection of basic and applied science. In particular the quinone research illustrates how African folk application of natural products, expertise in molecular electron flow and some knowledge of structure activity relationships can combine to produce a new application for this class of compounds. Probably our most important collaboration in this work, now eight years old, has been with the natural products group at the Mercer University School of Pharmacy, Atlanta, GA.
Applied science almost always leaves unanswered basic scientific questions. A major one is the actual toxicological action of the quinone-semiquinone redox cycling. This is the subject of proposed work with Dr. Carys Mitchelmore, who has extensive knowledge of quinone toxicology.
For a variety of logistical reasons, most of the research associated with the Ballast Water Treatment Project is centered in Baltimore where it has attracted a great deal of political support. The project now involves the Living Classroom Foundation, which has donated laboratory space and other reseources.
Follow-up work continues on the State of Maryland Ambient Toxicity Program, following the relocation of the Maryland Department of Natural Resources component to the EPA laboratory at Fort Meade, MD. A comprehensive, multi-authored paper summarizing this work throughout the 1990s is in preparation.
