Uranium in drinking water: understanding your lab result

Units and Canadian threshold

Health Canada’s maximum acceptable concentration (MAC) for total uranium is 0.02 mg/L, equal to 20 µg/L or 20 ppb. The guideline is based on the chemical toxicity of naturally occurring uranium, particularly kidney effects.

What one result can tell you

A result above 0.02 mg/L needs prompt follow-up with your laboratory and local public-health authority. Use an alternate source for drinking and cooking while you confirm the result. Do not assume taste, smell or clarity indicates whether uranium is present.

Retesting protocol

Use a laboratory accredited for the analysis and follow its bottle and flushing instructions. Retest the raw source and, if treatment is installed, collect a paired treated-water sample from the drinking tap. Keep both reports so performance can be compared over time.

Treatment and certification

Reverse osmosis can reduce uranium at a point-of-use drinking tap, but the exact reduction claim matters. Ask for third-party certification covering the target contaminant and test after installation. Whole-home ion exchange requires specialist design and careful management of uranium-bearing waste or regeneration media.

Limits

Point-of-use treatment protects only the connected faucet. This guide cannot diagnose health effects or replace an accredited result, public-health advice or a site-specific treatment design.