2/24/2009 US EPA
14) How did EPA evaluate the safety of monochloramine for use as a
drinking water disinfectant?
EPA evaluated monochloramine primarily through an analysis of
human health and animal data.
	Research reviewed in EPA's safety analysis is contained in EPA's
Drinking Water Criteria Document for Chloramines.1
	The criteria document for monochloramine provides a complete summary
of health and other data considered in establishing a monochloramine
	EPA periodically updates the monochloramine "criteria document."
EPA's monochloramine standard2 is set at a level where no human health
effects are expected to occur.
	Data from animal and human studies provide information on the health
effects of monochloramine.
	EPA reviews and considers new research results as they become
	EPA's standard for monochloramine takes data gaps and uncertainty into
account by building safety factors4 into the regulatory standard.
EPA reviewed historical data in its evaluation of monochloramine.
	Monochloramine has been in use as a drinking water disinfectant since
the 1930's.5
	Decades of use in the US, Canada, and Great Britain shows that
monochloramine is an effective secondary drinking water disinfectant.
	Denver, Philadelphia, and other large cities have used monochloramine as
part of their water treatment process for years.
Additional Supporting Information:
1.	The Drinking Water Criteria Document for Chloramines can be found at
http://www.epa.gov/ncea/pdfs/water/chloramine/dwchloramine.pdf. Publication No.:
ECAO-CIN-D002, March, 1994.
2.	The Maximum Residual Disinfectant Level (MRDL) for chloramines is 4 parts per
million (ppm).
3.	See the Contaminant Candidate List online at
http://www.epa.gov/OGWDW/ccl/ccl3.html for contaminants that EPA proposes to
review. EPA scientists review regulations of disinfectants and disinfection byproducts
every six years. For information on EPA's six-year review visit:
4.	For additional information regarding how uncertainty factors (also known as safety
factors) are applied to risk assessments to provide a wide margin of safety see:
5.	Cleveland, OH, Springfield, IL, and Lansing, Ml were among the first cities to use
monochloramine in 1929 (see Chapter 1 of The Quest for Pure Water Vol II, AWWA,