Standards and Regulations Related to BCDMH in Drinking Water
Bromochlorodimethylhydantoin or BCDMH is added to water to disinfect water or control microbial growth on the surfaces of water distribution system components. It possesses antimicrobial properties and is used in many applications, including the treatment of recreational and drinking water.
In groundwater wells, BCDMH is an effective control for slime-forming iron bacteria, thereby improving the aesthetic qualities of the water. BCDMH is typically a mixture of two related chemicals:
- 1-Bromo-3-chloro-5,5-dimethylhydantoin (CAS# 16079-88-2)
- 3-Bromo-1-chloro-5,5-dimethylhydantoin (CAS# 126-06-7).
Both chemicals release their chlorine and bromine components in water to create hypochlorous and hypobromous acid, which are the active antimicrobial agents.
BCDMH and FIFRA
Disinfectants such as BCDMH require EPA registration under FIFRA when used, sold or distributed within the United States. FIFRA registration is not a requirement of NSF/ANSI/CAN 60, because NSF/ANSI/CAN 60 is a human health effects standard and BCDMH can be used, sold and distributed in other countries.
Moreover, it is the responsibility of the chemical manufacturer or distributor to follow all applicable laws and regulations, including obtaining FIFRA registration for the U.S. market, and the responsibility of the municipal water utility to follow all applicable federal and state requirements for drinking water treatment and quality.
BCDMH Potential Contaminants
NSF/ANSI/CAN 60 establishes a minimum test battery for all BCDMH products and includes metals of toxicological concern, oxyhalides, and volatile organic compounds (VOCs). Metals analysis includes aluminum, antimony, arsenic, barium, beryllium, cadmium, chromium, copper, lead, manganese, mercury, selenium, and thallium. Oxyhalide analysis includes bromate, chlorate, and perchlorate. VOC analysis targets over sixty volatile organic compounds and includes both regulated and non-regulated compounds. All detected compounds shall not exceed the health effects criteria (SPAC) listed in NSF/ANSI/CAN Standard 600.
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