Ra
Radium-226 and Radium-228 (combined)
radionuclideSDWA code: 4010
EPA Limit (MCL)
No MCL
Health Goal (MCLG)
Zero (0)
No level is considered safe
Unit of Measure
pCi/L
How concentrations are reported
Combined MCL is 5 pCi/L. Measured in picocuries per liter, not mg/L.
Health Effects
Increased risk of cancer with long-term exposure. Bone cancer is of particular concern due to radium's affinity for bone tissue.
The EPA has set the health goal (MCLG) at zero, meaning no level of exposure is considered risk-free.
How It Gets Into Water
Erosion of natural deposits of certain minerals that are radioactive and may emit radioactive alpha particles
Official EPA Guidance
For authoritative information on Radium-226 and Radium-228 (combined)in drinking water, visit the EPA's official resource page.
View EPA Guidance ↗