Disinfection Byproducts

Chlorate

Anion comprised of chlorine and oxygen; a disinfection byproduct of chlorine dioxide water treatment and a component of the compound sodium chlorate

Health Guideline Level (HGL)

0.8 ppb

Maximum level that poses minimal health risk based on the latest science

Health Effects

Evidence surrounding the health effects of chlorate is limited. Health protective levels for chlorate have been developed based on hematological (blood system) and thyroid effects observed in animal studies.

Affected Organs & Systems:

Thyroid
Blood

Common Sources

  • Most often formed when chlorine dioxide is used for drinking water disinfection
  • Chlorine dioxide, a compound commonly used to control taste, odor, and harmful microorganisms in drinking water, rapidly converts into chlorate or related ions, chlorite (the most common byproduct) and chloride, on exposure to water
  • May also enter the environment through industrial release

How to Remove It

Water filters certified under the following NSF standards are effective at removing Chlorate:

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

Chlorate is classified as a Disinfection Byproducts contaminant.

This contaminant primarily affects the thyroid, blood.

Check Your Water

Find out if Chlorate is in your tap water.

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