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Update: May 2004

Current Massachusetts Regulatory Limit
MMCL = Treatment Technique. (Refer to 310 CMR 22.20.) ORS has adopted the MCL published by the U.S. EPA.

Federal Regulatory Limit
The MCL for Cryptosporidium is a Treatment Technique. Under U.S. EPA's Surface Water Treatment Rule, systems using surface water or groundwater under the direct influence of surface water must achieve a 99% removal of Cryptosporidium (as of 1/1/02 for systems serving greater than 10,000 and 1/14/05 for systems serving less than 10,000). The MCLG is equal to zero.

Basis for Criteria
The MCL for Cryptosporidium is based on a Treatment Technique as described above.

Critical Effects
Cryptosporidium is an organism found in rivers and lakes especially in those contaminated with human or animal wastes. It is fairly resistant to disinfection and even a well-operated facility cannot ensure that the water will not contain this organism. The water treatment technique is based on filtration. Cryptosporidium has produced several large waterborne disease outbreaks with gastrointestinal symptoms including diarrhea, nausea, and/or stomach cramps (US. EPA, 1999).

Cancer Assessment: 

Biological Pathogen

Analytical Information
: See U.S. EPA Method 1623 (U.S. EPA, 2001)

Analytical Methods
U.S. EPA Method 1623

PQLs and analytical methods may have been updated since this guidance value was last revised. Updated analytical methods for drinking water and their associated PQLs may be found at US EPA Drinking Water Analytical Methods .

Federal Register. January 14, 2002. Environmental Protection Agency. Parts 9, 141 and 142. National Primary Drinking Water Regulations: Long Term 1 Enhanced Surface Water Treatment Rule. Final Rule. (67 FR 1811).

U.S. Environmental Protection Agency (U.S. EPA). June 1999. Guidance for People With Severely Weakened Immune Systems. U.S. EPA-816-F-99-005. Office of Water.

U.S. Environmental Protection Agency (U.S. EPA). April 2001. Method 1623: Cryptosporidium and Giardia in Water by Filtration/IMS/FA. EPA-821-R-01-025. Office of Water.

U.S. Environmental Protection Agency (U.S. EPA). July 2002. List of Contaminants and Their MCLs. EPA 816-F-02-013.