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Environmental Health - Toxic Substances



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USGS scientist working with a microcosm containing sediments from a subsurface gasoline plume at a leaking underground storage tank in Galloway Township, New Jersey [/sites/gall_page.html] . The microcosm work was part of a study on the natural attenuation of a gasoline spill
A USGS scientist collecting water samples anaerobically in a glove bag as part of a study of the processes that control the biotransformation of contaminants in a subsurface plume of landfill leachate at the Norman Municipal Landfill, Norman, Okla.
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Biotransformation – "Chemical conversion of a substance that is mediated by living organisms or enzyme preparations derived there from." - Stephenson and others, 2006

Biotransformation - "Biotransformation is the process whereby a substance is changed from one chemical to another (transformed) by a chemical reaction within the body." – National Library of Medicine and Monosson, 2007

Biotransformation or microbial transformation – "The use of living organisms to modify substances that are not normally used for growth." – Prescott and others, 2002

Biotransformation – "The series of chemical reactions that occur in a compound, especially a drug, as a result of enzymatic or metabolic activities by a living organism." - McGraw-Hill Companies, 2003

Biotransformation - "Chemical alteration of a substance within the body, as by the action of enzymes." - Editors of the American Heritage Dictionaries, 2000

Related Definitions



Aerobic Biodegradation


Anaerobic Biodegradation


Electron Acceptor

Electron Donor

Natural Attenuation

USGS Information on Biodegradation

Related Headlines

Other Information on Biodegradation


Editors of the American Heritage Dictionaries, 2000, The American heritage dictionary of the English language (4 ed.): Houghton Mifflin Company, 2076 p.

McGraw-Hill Companies, 2003, Biotransformation, in AccessScience--McGraw-Hill Encyclopedia of Science and Technology Online: The McGraw-Hill Companies, access date July 18, 2007.

National Library of Medicine (content source), Emily Monosson (editor), 2007, Biotransformation, in Cleveland, C.J., ed., Encyclopedia of Earth: Washington, D.C., Environmental Information Coalition, National Council for Science and the Environment, access date July 18, 2007.

Prescott, L.M., Klein, D.A., and Harley, J.P., 2002, Microbiology--Online learning center (5th ed.): McGraw-Hill Higher Education, p.

Stephenson, G.R., Ferris, I.G., Holland, P.T., and Nordberg, M., 2006, Glossary of terms relating to pesticides (IUPAC Recommendations 2006): Pure and Applied Chemistry, v. 78, no. 11, p. 2,075-2,154, doi:10.1351/pac200678112075.


Disclaimer: The definitions on this page are provided for information purposes only, and do not indicate endorment by the U.S. Geological Survey.

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