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Credits and Acknowledgements


The encylopedia was compiled and edited in February 1998 by Roy J. Irwin, National Park Service, with assistance from Colorado State University student contaminant specialists Mark Van Mouwerik, Lynette Stevens, Marion Dubler Seese, and Wendy Basham.


The editors gratefully acknowledge the assistance of a very large number of contaminant specialists and environmental toxicologists who contributed suggestions, editing, and personal communications (as cited throughout the text) or helped encourage the senior editor to begin and continue this work. The list is too long to include here. It includes many colleagues from the Society of Environmental Toxicology and Chemistry, as well as colleagues in numerous state and federal agencies.

The U.S. Fish and Wildlife Service is acknowledged for helping support some of the early stages of this effort. Special assistance was provided by staff of the United States Geological Survey, Environmental Protection Agency, Bureau of Reclamation, Bureau of Land Management, Department of Energy, National Library of Medicine, Agency for Toxic Substances and Disease Registry, and various Department of Defense agencies.

The Environmental Response Planning and Assessment Unit (Oil Spill Response) office of the National Park Service, directed by Dan Hamson, provided funding for the oil spill-related portions of this product.

Additional funds and/or authorization to use staff time for development of the product were provided by other National Park Service Staff: Shawn Norton of the Hazardous Waste Program, Dan Kimball of the Water Resources Division (WRD), and Bill Jackson of the Water Operations Branch (WRD).

Gary Rosenlieb, Dean Tucker, and Barry Long of the Park Service Water Resources Division provided frequent assistance, ideas or encouragement, as did a very large number of colleagues in other agencies such as the U.S. Fish and Wildlife Service, the U.S. Geological Survey, and the Environmental Protection Agency.

Appreciation is extended to Lewis Publishers and the many other publishers and authors who gave copyright permission to reprint pieces of text.

The senior editor acknowledges the efforts of Colorado State University staff, including John Stednick of the Earth Resources Department, to obtain graduate student assistants to work on this project.

Citing This Document

For critical applications, it would be better to obtain and cite the original publication after first verifying the information to be used. It may also be necessary to talk to the authors of the original reference to satisfy various data quality assurance concerns before using a particular piece of information.

For more routine applications, this document may be cited as:

Irwin, R.J., M. VanMouwerik, L. Stevens, M.D. Seese, and W. Basham. 1998. Environmental Contaminants Encyclopedia. National Park Service, Water Resources Division, Fort Collins, Colorado. Distributed on the Internet at

References List

The references list for the encyclopedia is available as a PDF (251KB). References are documented as numbers within brackets, using the format of the Journal of Environmental Toxicology and Chemistry, with all references listed in numerical order.

Last Updated: January 03, 2017