National Drinking Water Database
Bromate in North Carolina
Bromate is a carcinogenic disinfection byproduct of ozonation formed when source waters contain high levels of natural bromide; it can also form following water treatment with chlorine dioxide or hypochlorite. [read more]
Bromate is a chemical byproduct of drinking water disinfection with ozone. Bromate is formed when ozone reacts with naturally occurring bromide found in source water (Richardson 2007; U.S. Environmental Protection Agency (USEPA) 2009b; WHO 2004a). Bromate may also form following chlorine dioxide treatment (Gordon 1990; Richardson 2003; WHO 2004A) or from use of hypochlorite as water disinfectant (Bolyard 1992).
Of all disinfection byproducts regulated by EPA, bromate is the most potent carcinogen in laboratory animals (Richardson 2007). Bromate causes tumors of the kidney, thyroid, and lining of the abdominal cavity and internal organs (mesotheliomas) in rats. Bromate is thought to cause these tumors by damaging DNA, both by causing mutations and damaging chromosomes. Recently, the Environmental Protection Agency (EPA) concluded that chemicals that cause mutations are more carcinogenic when exposure occurs during infancy and childhood (Integrated Risk Information System (IRIS) 2001). The International Agency for Research on Cancer classified bromate as possibly carcinogenic to humans (IARC 2008b).
In view of bromate's high toxicity, EPA has set a Maximum Contaminant Level Goal (MCLG) for bromate in drinking water at zero. (MCLG is the level of a contaminant in drinking water below which there is no known or expected risk to health).
Acute bromate poisoning (mostly through ingestion of permanent hair neutralizing solution) include symptoms such as fatigue, central nervous system depression, abdominal pain, vomiting and other gastrointestinal tract symptoms. After several hours, the kidneys begin to fail and more than half the people so poisoned permanently lose their hearing. People with pre-existing kidney conditions and diabetes may be more susceptible to bromate toxicity. The kidney is also a target organ of bromate in laboratory animal studies (Integrated Risk Information System (IRIS) 2001).
The Most Polluted Communities in North Carolina
1 water utilities reported detecting Bromate in tap water since 2004, according to EWG's analysis of water quality data supplied by state water agencies
Ranked by highest average Bromate level
|Rank||System||Population Served||Positive test results of total reported tests||Average Level|
|1||Greenville Utilities Comm|
|83,210||3 of 51||0.59 ppb|
(0 to 10 ppb)
Health Based Limits for Bromate
|Maximum Contaminant Limit Goal (MCLG)||A non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.||0 ppb|
|One in one million (10-6) Cancer Risk||The concentration of a chemical in drinking water corresponding to an excess estimated lifetime cancer risk of 1 in 1,000,000. Source: U.S. Environmental Protection Agency.||0.05 ppb|
|One in ten thousand (10-4) Cancer Risk||The concentration of a chemical in drinking water corresponding to an excess estimated lifetime cancer risk of 1 in 10,000. Source: U.S. Environmental Protection Agency.||5 ppb|
|Maximum Contaminant Limit (MCL)||The enforceable standard which defines the highest level of a contaminant that is allowed in drinking water. MCLs are set as close to health-based limits (Maximum Contaminant Level Goals, or MCLGs) as feasible using the best available analytical and treatment technologies and taking cost into consideration. Source: U.S. Environmental Protection Agency.||10 ppb|
|Drinking Water Equivalent Level||A lifetime exposure concentration protective of adverse, noncarcinogenic health effects, that assumes all of the exposure to a contaminant is from drinking water. Source: U.S. Environmental Protection Agency.||140 ppb|
|Children's health-based limit for 1-day exposure||Concentration of a chemical in drinking water that is not expected to cause any adverse, noncarcinogenic health effects for up to one day of exposure. The One-Day health-based limit (or Health Advisory, HA) is typically set to protect a 10-kg child consuming 1 liter of water per day. Source: U.S. Environmental Protection Agency.||200 ppb|
Violation Summary for Bromate in North Carolina
Data from the U.S. Environmental Protection Agency includes the following violations of federal standards in North Carolina since 2004
|Violation Type||Number of Violations|
|Monitoring and Reporting Disinfection Byproduct Rule||1|