Uranium in Drinking Water

Uranium is a common naturally occurring and radioactive substance. It is a normal part of rocks, soil, air and water. Uranium occurs in nature in the form of minerals, but never as a metal. Uranium enters water by leaching from soil and rocks, or in releases from processing plants. Uranium has demonstrated toxic effects on human kidneys leading to their inflammation and changes in urine composition. Uranium can decay into other radioactive substances, such as radium, which can cause cancer with extensive exposure over a long period of time (U.S. EPA, 2013).

Contaminant In Water As Maximum Contaminant Level
Uranium (U)


MCL* = 0.030 mg/L (or ppm)
MCLG** = zero mg/L (or ppm)

WHO† Guideline = 0.030 mg/L

Sources of Contaminant

Naturally occurring mineral

Potential Health Effects

Kidney toxicity
Increased risk of cancer

Treatment Methods

Point-of-Entry (POE)

Point-of-Use (POU)

Strong Base Anion Exchange Resins (Cl- form)
Reverse Osmosis

*Maximum Contaminant Level (MCL) - The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs as feasible using the best available treatment technology and taking cost into consideration. MCLs are enforceable standards.

**Maximum Contaminant Level Goal (MCLG) - The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety and are non-enforceable public health goals.

WHO† - World Health Organization

Click here to open WQA's Technical Fact Sheet on Uranium.

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