Chlorate

IL American-fernway

NOTE: IL American-fernway purchases water from Tinley Park which is required to test for chlorate. Sample information shown below was taken by Tinley Park.

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.

MORE ABOUT THIS CONTAMINANT

Samples

Samples exceeding legal limit (MCL)

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Range of results
2014	ND	2	ND
2015	ND	6	ND
2016	N/A	0	N/A
2017	N/A	0	N/A
2018	N/A	0	N/A
2019	N/A	0	N/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

NOTE: IL American-fernway purchases water from Tinley Park which is required to test for chlorate. Sample information shown below was taken by Tinley Park.

Date	Lab ID	Result
2013-04-10	21526801	ND
2013-04-10	21526701	ND
2013-04-10	21526601	ND
2013-07-10	22907801	ND
2013-08-07	22907901	ND
2013-10-09	23771801	ND
2013-10-09	23771701	ND
2013-10-09	23771901	ND
2014-01-13	24483401	ND
2014-01-13	24483301	ND