Know Your Environment. Protect Your Health.

Chlorate

Vera Water & Power

Chlorate forms in drinking water as a byproduct of disinfection. Chlorate impairs thyroid function, making chlorate exposure most harmful during pregnancy and childhood. Read More.

In 2002, California scientists proposed an advisory value, called an action level, for chlorate at 200 parts per billion. Between 2013 and 2015, the EPA collected data through the Unregulated Contaminant Monitoring Rule program and found that over 15 percent of water tests from 38 percent of utilities had chlorate levels above a health-protective concentration, which federal scientists defined as 210 parts per billion, nearly equivalent to the California advisory value.

Click here to read more about disinfection byproducts.

 

24

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20156.29 ppb241ND - 151.0 ppb
2016N/A00N/A
2017N/A00N/A
2018N/A00N/A
2019N/A00N/A
2020N/A00N/A
2021N/A00N/A
2022N/A00N/A
2023N/A00N/A

ppb = parts per billion

State, National, and Health Guidelines for Drinking Water

EWG Health Guideline: 210 ppb

The EWG Health Guideline of 210 ppb for chlorate was defined by the Environmental Protection Agency as a benchmark for testing under the Unregulated Contaminant Monitoring Rule program. This health guideline protects against hormone disruption.

ppb = parts per billion

All test results

Date Lab ID Result
2015-07-13WA97-SE1-15-14867-33213ND
2015-07-13WA97-SE1-15-14867-33216ND
2015-07-13WA97-SE1-15-14867-33218ND
2015-07-13WA97-SE1-15-14867-33217ND
2015-07-13WA97-SE1-15-14867-33215ND
2015-07-13WA97-SE1-15-14867-33222ND
2015-07-13WA97-SE1-15-14867-33223ND
2015-07-13WA97-SE1-15-14867-33220ND
2015-07-13WA97-SE1-15-14867-33219ND
2015-07-13WA97-SE1-15-14867-33221ND
2015-07-13WA97-SE1-15-14867-33224ND
2015-07-13WA97-SE1-15-14867-33214ND
2015-12-02WA97-SE2-15-26413-59106ND
2015-12-02WA97-SE2-15-26413-59102ND
2015-12-02WA97-SE2-15-26413-59103ND
2015-12-02WA97-SE2-15-26413-59104151.0 ppb
2015-12-02WA97-SE2-15-26413-59107ND
2015-12-02WA97-SE2-15-26413-59105ND
2015-12-03WA97-SE2-15-26413-59110ND
2015-12-03WA97-SE2-15-26413-59112ND
2015-12-03WA97-SE2-15-26413-59111ND
2015-12-03WA97-SE2-15-26413-59109ND
2015-12-03WA97-SE2-15-26413-59108ND
2015-12-03WA97-SE2-15-26413-59113ND