Know Your Environment. Protect Your Health.

Chlorate

Ruston Water System

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.

 

37

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014ND360ND
2015ND10ND
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
2014-05-013019237ND
2014-05-013019355ND
2014-05-013019323ND
2014-05-013019342ND
2014-05-013019289ND
2014-05-013019271ND
2014-05-013019363ND
2014-05-013019311ND
2014-05-013019245ND
2014-05-013019263ND
2014-05-013019337ND
2014-05-013019350ND
2014-05-023019258ND
2014-05-023019250ND
2014-05-023019276ND
2014-05-023019224ND
2014-05-023019284ND
2014-05-023019232ND
2014-11-113138083ND
2014-11-113137987ND
2014-11-113138344ND
2014-11-113137897ND
2014-11-113138365ND
2014-11-113138161ND
2014-11-113138196ND
2014-11-113137905ND
2014-11-113138103ND
2014-11-113138326ND
2014-11-113138004ND
2014-11-113138242ND
2014-11-113138284ND
2014-11-113138256ND
2014-11-113138150ND
2014-11-113138181ND
2014-11-113138318ND
2014-11-113138294ND
2015-01-123168375ND