Gross Alpha Activity
Gross alpha activity measures the total amount of radioactivity in a water sample emitted by decaying alpha-emitting elements, notably radioactive isotopes of uranium, radium, and radon. Alpha emitters are used to treat cancer, as an eliminator of static in paper mills and in other products like smoke detectors. Radioactive atoms release high energy alpha particles that pull electrons off of the atoms in cells. This process is called ionizing radiation, and may lead to harmful changes in cells and tissues. The toxicity of an alpha emitter depends on the amount of energy it releases and how organ systems respond to that energy. Exposure to elevated gross alpha activity is associated with increased cancer risk and genotoxicity, but toxicity to individual systems is dependent on the type of alpha emitter present.
Health Guideline Level (HGL)
0 ppb
Maximum level that poses minimal health risk based on the latest science
Health Effects
Drinking water standards for gross alpha activity have been developed based on increased cancer risk associated with alpha radioactivity. Alpha radiation has been shown to produce DNA changes (genotoxicity) in laboratory studies.
Affected Organs & Systems:
Common Sources
- Gross alpha radiation results from the decay of radionuclides from both natural and human-made deposits. Alpha-emitting particles are widespread in the environment and are released into drinking water by the natural leaching of rocks. Elevated gross alpha activity in drinking water may occur in areas of high mining activity, or in areas where the bedrock contains high levels of radioactive elements.
How to Remove It
Water filters certified under the following NSF standards are effective at removing Gross Alpha Activity:
Health Guideline Level
The HGL represents the maximum level that poses minimal health risk based on the latest scientific research. It's often more protective than federal legal limits.
Contaminant Type
Gross Alpha Activity is classified as a Radionuclides contaminant.
This contaminant primarily affects the carcinogens.
Check Your Water
Find out if Gross Alpha Activity is in your tap water.
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