National Drinking Water Database

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National Drinking Water Database - Chemical Contaminants

Gross beta particle activity (mrem/yr)

Status: Regulated - EPA has established a maximum legal limit in tapwater for this contaminant.

Beta particles are a form of radiation frequently associated with nuclear testing and radioactive mineral deposits. [read more]

Beta particles Beta particles are high energy, negatively charged particles (electrons). Beta particles are emitted from the decay of natural and man-made deposits of unstable isotopes of radioactive compounds such as tritium, carbon-14, cobalt-60, strontium-90 and iodine-129. Similar to alpha particles, beta particles are a form of ionizing radiation that detaches electrons from atoms or molecules and forms ions. This property is responsible for the DNA damage and DNA mutations associated with exposure to beta particles. A drinking water contaminant fact sheet written by EPA notes that exposure to beta particles and photon emitters in drinking water above the maximum contaminant level (MCL) of four millirems per year may cause cancer (U.S. Environmental Protection Agency (USEPA) 2009b).

	Detected	Found above health guidelines	Found above legal limit
States	2	2	1
Water utilities	3	3	1
People Served	317,287	317,287	50,004

Gross beta particle activity (mrem/yr) Exposure by State

Water utilities in 2 states have reported detecting Gross beta particle activity (mrem/yr) in treated tap water since 2004, according to EWG's analysis of water quality data supplied by state water agencies.

State	Water Suppliers with Gross beta particle activity (mrem/yr) contamination		Water suppliers reporting Gross beta particle activity (mrem/yr) above health-based limits
	Systems	Population	Systems	Population
Delaware	1	201,000	1	201,000
Florida	2	116,287	2	116,287
Total	3	317,287	3	317,287

The Most Polluted Communities

3 water utilities reported detecting Gross beta particle activity (mrem/yr) in tap water since 2004, according to EWG's analysis of water quality data supplied by state water agencies

Ranked by highest average Gross beta particle activity (mrem/yr) level

Rank	System	Population Served	Positive test results of total reported tests	Average Level (Range)
1	Wellington Wtp Wellington, FL	50,004	1 of 1	9 mrem/yr (9 mrem/yr)
2	Artesian Water Company Newark, DE	201,000	2 of 2	2.6 mrem/yr (2.24 to 2.95 mrem/yr)
3	Winter Garden Water Dept (3 Wps) Winter Garden, FL	66,283	3 of 3	1.68 mrem/yr (0.83 to 2.5 mrem/yr)

Health Based Limits for Gross beta particle activity (mrem/yr)

Standard	Description	Level
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 mrem/yr
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.	0.04 mrem/yr
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.	4 mrem/yr
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.	4 mrem/yr

Testing Summary for Gross beta particle activity (mrem/yr)

Are tests routinely required for Gross beta particle activity (mrem/yr) by federal law?	Yes
Water suppliers reporting tests for Gross beta particle activity (mrem/yr) (2004-2008):	177 of 47,576
Average testing rate for water supplier reporting tests (2004-2008):	0.4 per year

Violation Summary for Gross beta particle activity (mrem/yr)

Data from the U.S. Environmental Protection Agency includes the following violations of federal standards for Gross beta particle activity (mrem/yr) since 2004

Maximum Contaminant Level Exceedance Violations	1
Monitoring Violations	68
Reporting Violations	0