Menu

EWG's Tap Water Database — 2019 UPDATE

Donate

Chlorate

City of North Platte

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.

 

54

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2012N/A00N/A
2013ND280ND
2014ND260ND
2015N/A00N/A
2016N/A00N/A
2017N/A00N/A

ppb = parts per billion

State and national drinking water standards and health guidelines

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
2013-10-01201310030367AMND
2013-10-01201310030387AMND
2013-10-01201310040263AMND
2013-10-01201310030486AMND
2013-10-01201310030407AMND
2013-10-01201310030247AMND
2013-10-01201310030462AMND
2013-10-01201310030497AMND
2013-10-01201310030397AMND
2013-10-01201310030394AMND
2013-10-01201310030488AMND
2013-10-01201310030381AMND
2013-10-01201310030175AMND
2013-10-01201310030318AMND
2013-10-02201310040131AMND
2013-10-02201310040126AMND
2013-10-02201310040158AMND
2013-10-02201310040154AMND
2013-10-02201310040270AMND
2013-10-02201310040156AMND
2013-10-02201310040143AMND
2013-10-02201310040232AMND
2013-10-02201310040150AMND
2013-10-02201310040242AMND
2013-10-02201310040166AMND
2013-10-02201310040208AMND
2013-10-02201310040117AMND
2013-10-02201310040139AMND
2014-04-14201404160577AMND
2014-04-14201404160569AMND
2014-04-14201404160626AMND
2014-04-14201404160594AMND
2014-04-14201404160573AMND
2014-04-14201404160896AMND
2014-04-14201404160892AMND
2014-04-14201404160738AMND
2014-04-14201404160640AMND
2014-04-14201404160823AMND
2014-04-14201404160608AMND
2014-04-14201404160602AMND
2014-04-14201404160561AMND
2014-04-14201404160903AMND
2014-04-15201404160812AMND
2014-04-15201404160624AMND
2014-04-15201404160575AMND
2014-04-15201404160600AMND
2014-04-15201404160598AMND
2014-04-15201404160825AMND
2014-04-15201404160831AMND
2014-04-15201404160634AMND
2014-04-15201404160915AMND
2014-04-15201404160606AMND
2014-04-15201404160616AMND
2014-04-15201404160632AMND