National Drinking Water Database

• Read the Research
• Get a Water Filter
• Tips for Safe Water
• FAQs
• EWG Needs Your Help. As little as $5 can help.

Alpha particle activity (excl radon and uranium) in Maryland

---

Alpha particles are a form of radiation associated with radioactive mining waste pollutants and natural sources. [read more]

Alpha particles Alpha particles are high energy, positively charged radioactive particles. They are emitted from natural deposits of unstable isotopes of radioactive mineral compounds such as uranium-238, radium-226, radon-222, and plutonium-236. Alpha particles are classified as "ionizing radiation" due to their ability to detach electrons from atoms or molecules and form ions. This property is responsible for the DNA damage and DNA mutations associated with exposure to alpha particles. A drinking water contaminant fact sheet written by EPA notes that exposure to alpha particles in drinking water above the maximum contaminant level (MCL) of 15 pCi/L may increase cancer risk (U.S. Environmental Protection Agency (USEPA) 2009b).

The Most Polluted Communities in Maryland

168 water utilities reported detecting Alpha particle activity (excl radon and uranium) in tap water since 2004, according to EWG's analysis of water quality data supplied by state water agencies

Ranked by highest average Alpha particle activity (excl radon and uranium) level

Rank	System	Population Served	Positive test results of total reported tests	Average Level (Range)
1	Eastern Correctional Institute Westover, MD	3,500	1 of 1	25 pCi/L (25 pCi/L)
2	Mount Saint Mary's University Emmitsburg, MD	1,900	10 of 10	20.1 pCi/L (9 to 27 pCi/L)
3	Town of Poolesville Poolesville, MD	5,100	27 of 27	19.21 pCi/L (1 to 38 pCi/L)
4	Stoney Chase/ Rock Creek M.H.P.'s Elkton, MD	396	1 of 1	19 pCi/L (19 pCi/L)
5	Harbor View Charlestown, MD	437	12 of 12	18.25 pCi/L (5 to 35 pCi/L)
6	Concord Estates Mobile Home Park Waldorf, MD	150	17 of 17	16.54 pCi/L (4.1 to 39 pCi/L)
7	Chapel Point Woods La Plata, MD	278	11 of 11	15.89 pCi/L (1.03 to 44.7 pCi/L)
8	Golden Kay Apartments Elkton, MD	89	13 of 14	15.43 pCi/L (0 to 29 pCi/L)
9	Graymount Apartments Perryville, MD	27	12 of 12	13.75 pCi/L (3 to 25 pCi/L)
10	Town of New Windsor New Windsor, MD	1,100	2 of 2	12.5 pCi/L (12 to 13 pCi/L)

Health Based Limits for Alpha particle activity (excl radon and uranium)

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 pCi/L
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.	0.15 pCi/L
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.	15 pCi/L
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.	15 pCi/L

Violation Summary for Alpha particle activity (excl radon and uranium) in Maryland

Data from the U.S. Environmental Protection Agency includes the following violations of federal standards in Maryland since 2004

Violation Type	Number of Violations
Over maximum contaminant level, Average	13