Know Your Environment. Protect Your Health.

Chlorate

Tangipahoa Parish Water District

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.

 

30

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014ND140ND
2015ND160ND
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
2014-12-1835168699027AMND
2014-12-1835168699007AMND
2014-12-1835168699003AMND
2014-12-1835168699011AMND
2014-12-1835168699009AMND
2014-12-1835168699021AMND
2014-12-1835168699019AMND
2014-12-1835168699015AMND
2014-12-1835168699025AMND
2014-12-1835168699017AMND
2014-12-1835168699023AMND
2014-12-1835168699013AMND
2014-12-1835168699001AMND
2014-12-1835168699005AMND
2015-06-2435194588013AMND
2015-06-2435194588003AMND
2015-06-2435194588011AMND
2015-06-2435194588001AMND
2015-06-2435194588031AMND
2015-06-2435194588007AMND
2015-06-2435194588005AMND
2015-06-2435194588015AMND
2015-06-2435194588029AMND
2015-06-2435194588009AMND
2015-06-2435194588023AMND
2015-06-2435194588027AMND
2015-06-2435194588017AMND
2015-06-2435194588025AMND
2015-06-2435194588019AMND
2015-06-2435194588021AMND