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USGS personnel collect a water-quality sample on the Missouri River. USGS/Photo by Kelly Brady.
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7.3 Protozoan Pathogens (11/2003) [1.2 MB PDF]
By R.N. Bushon and D.S. Francy
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Protozoan pathogens are widely distributed in the aquatic environment. Cryptosporidium and Giardia are the principal protozoan pathogens that are known to affect the acceptability of water supplies for public use within the United States. A sampling program for protozoan pathogens should be conducted over an extended period of time because of cyclical and seasonal variations in their concentrations in the environment. This report provides information on the equipment, sampling protocols, and laboratory method that are in standard use by U.S. Geological Survey (USGS) personnel for the collection of data on protozoan pathogens.
7.3 Protozoan pathogens
7.3.1 - Sterilization procedures for sampling equipment
7.3.2 - Sample collection, preservation, transport, and holding times
7.3.3 - Laboratory method: USEPA Method 1623
7.3.4 - Calculation and reporting of protozoan pathogens
Citation for Section 7.3
Bushon, R.N., and Francy, D.S., 2003, Protozoan pathogens: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chap. A7, section 7.3, November, accessed __ list date __ from http://pubs.water.usgs.gov/twri9A/.