Barium in Drinking Water

Barium is a divalent cation and alkaline earth metal that can be found in naturally occurring mineral deposits. The health effects of the different barium compounds depend on how well the compound dissolves in water. Barium compounds that do not dissolve well in water are not generally harmful and are often used by doctors for medical purposes.

Contaminant  In Water As Maximum Contaminant Level



Barium (Ba)







MCL* = 2.0 mg/L (or ppm)

MCLG** = 2.0 mg/L

WHO† Guideline = 0.7 mg/L

Health Canada MAC*** = 1.0 mg/L

 Sources of Contaminant

  • Mineral deposits
  • Disposal of drilling wastes
  • Smelting of copper
  • Motor vehicle parts manufacturing

Potential Health Effects

Difficulties in breathing, increased blood pressure, changes in heart rhythm, stomach irritation, brain swelling, muscle weakness, and damage to the liver, kidney, heart, and spleen.

Treatment Methods

Point-of-Entry (POE)

Point-of-Use (POU)

  • Cation exchange
  • Reverse Osmosis
  • Distillation

*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.

***Maximum Acceptable Concentration (MAC) – Health Canada regulated highest level allowed in drinking water.

WHO† - World Health Organization


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

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