Chlorite

Montgomery County Regional Public Water Authority

Chlorite is a disinfection byproduct resulting from water treatment with chlorine dioxide. Chlorite decreases hemoglobin levels and causes other hematologic effects. Read More.

Chlorite also forms when chlorine dioxide is used as a bleaching agent for textiles, paper pulp, flour and oils, and from the use of chlorine dioxide in food and packaging.� In 2009, California published a public health goal of 50 parts per billion for chlorite in drinking water. California state scientists reported that chlorite causes red blood cell damage, affects sperm and thyroid function, and may alter behavior and neurodevelopment of rat pups exposed in the womb.

Click here to read more about disinfection byproducts.

MORE ABOUT THIS CONTAMINANT

206

Samples

Samples exceeding legal limit (MCL)

144

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Detections	Range of results
2014	398.6 ppb	26	21	ND - 783.0 ppb
2015	747.4 ppb	36	36	144.0 ppb - 1,270.0 ppb
2016	386.5 ppb	36	33	ND - 998.0 ppb
2017	460.4 ppb	36	28	ND - 875.0 ppb
2018	196.4 ppb	36	18	ND - 939.0 ppb
2019	178.5 ppb	36	11	ND - 855.0 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 50 ppb

The EWG Health Guideline of 50 ppb for chlorite was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against change in blood chemistry.

EPA Maximum Contaminant
Level (MCL) 1,000 ppb

ppb = parts per billion

All test results

Date	Lab ID	Result
2014-04-22	141140003	167.0 ppb
2014-04-22	141140001	218.0 ppb
2014-04-22	141140002	208.0 ppb
2014-05-06	141280031	277.0 ppb
2014-05-06	141280030	278.0 ppb
2014-05-06	141280032	433.0 ppb
2014-06-04	141560018	448.0 ppb
2014-06-04	141560017	469.0 ppb
2014-06-04	141560019	447.0 ppb
2014-07-02	141840018	563.0 ppb
2014-07-02	141840019	524.0 ppb
2014-07-02	141840020	783.0 ppb
2014-08-04	142190055	ND
2014-08-04	142190056	ND
2014-08-04	142190057	ND
2014-09-02	142470030	590.0 ppb
2014-09-02	142470029	ND
2014-09-02	142470028	ND
2014-10-07	Y142820040	742.0 ppb
2014-10-07	Y142820042	773.0 ppb
2014-10-07	Y142820041	713.0 ppb
2014-11-04	Y143100039	675.0 ppb
2014-11-04	Y143100038	655.0 ppb
2014-11-04	Y143100037	611.0 ppb
2014-12-01	Y143380046	67.7 ppb
2014-12-01	Y143380048	722.0 ppb
2015-01-07	Y150080039	774.0 ppb
2015-01-07	Y150080038	808.0 ppb
2015-01-07	Y150080040	841.0 ppb
2015-02-02	Y150360037	620.0 ppb
2015-02-02	Y150360036	620.0 ppb
2015-02-02	Y150360035	596.0 ppb
2015-03-02	Y150630009	557.0 ppb
2015-03-02	Y150630008	570.0 ppb
2015-03-02	Y150630010	563.0 ppb
2015-04-06	Y150990040	786.0 ppb
2015-04-06	Y150990038	817.0 ppb
2015-04-06	Y150990039	841.0 ppb
2015-05-04	Y151270009	959.0 ppb
2015-05-04	Y151270010	901.0 ppb
2015-05-04	Y151270008	952.0 ppb
2015-06-02	Y151550035	1,090.0 ppb
2015-06-02	Y151550034	1,160.0 ppb
2015-06-02	Y151550033	1,270.0 ppb
2015-07-07	Y151910010	144.0 ppb
2015-07-07	Y151910011	217.0 ppb
2015-07-07	Y151910012	649.0 ppb
2015-08-03	Y152180056	792.0 ppb
2015-08-03	Y152180057	779.0 ppb
2015-08-03	Y152180058	794.0 ppb
2015-09-01	Y152460017	760.0 ppb
2015-09-01	Y152460015	963.0 ppb
2015-09-01	Y152460016	979.0 ppb
2015-10-06	Y152820041	900.0 ppb
2015-10-06	Y152820040	919.0 ppb
2015-10-06	Y152820039	710.0 ppb
2015-11-04	Y153100020	561.0 ppb
2015-11-04	Y153100019	913.0 ppb
2015-11-04	Y153100021	572.0 ppb
2015-12-02	Y153370045	524.0 ppb
2015-12-02	Y153370043	556.0 ppb
2015-12-02	Y153370044	451.0 ppb
2016-01-04	Y160080069	497.0 ppb
2016-01-04	Y160080070	486.0 ppb
2016-01-04	Y160080071	453.0 ppb
2016-02-02	Y160350015	544.0 ppb
2016-02-02	Y160350016	552.0 ppb
2016-02-02	Y160350017	482.0 ppb
2016-03-01	Y160630008	440.0 ppb
2016-03-01	Y160630009	402.0 ppb
2016-03-01	Y160630010	377.0 ppb
2016-04-04	Y160980033	385.0 ppb
2016-04-04	Y160980031	438.0 ppb
2016-04-04	Y160980032	129.0 ppb
2016-05-03	Y161260008	613.0 ppb
2016-05-03	Y161260009	614.0 ppb
2016-05-03	Y161260010	440.0 ppb
2016-06-06	Y161610011	402.0 ppb
2016-06-06	Y161610012	410.0 ppb
2016-06-06	Y161610013	351.0 ppb
2016-07-05	Y161890023	296.0 ppb
2016-07-05	Y161890025	328.0 ppb
2016-07-05	Y161890026	325.0 ppb
2016-08-01	Y162210035	998.0 ppb
2016-08-01	Y162210036	997.0 ppb
2016-08-01	Y162210037	594.0 ppb
2016-09-06	Y162520014	ND
2016-09-06	Y162520015	ND
2016-09-06	Y162520016	ND
2016-10-03	Y162800017	252.0 ppb
2016-10-03	Y162800018	154.0 ppb
2016-10-03	Y162800019	222.0 ppb
2016-11-02	Y163090029	250.0 ppb
2016-11-02	Y163090030	318.0 ppb
2016-11-02	Y163090031	238.0 ppb
2016-12-06	Y163420030	310.0 ppb
2016-12-06	Y163420031	309.0 ppb
2016-12-06	Y163420032	308.0 ppb
2017-01-03	Y170050039	512.0 ppb
2017-01-03	Y170050040	517.0 ppb
2017-01-03	Y170050041	505.0 ppb
2017-02-01	Y170340021	470.0 ppb
2017-02-01	Y170340022	425.0 ppb
2017-02-01	Y170340023	498.0 ppb
2017-03-07	Y170670013	457.0 ppb
2017-03-07	Y170670014	448.0 ppb
2017-03-07	Y170670015	497.0 ppb
2017-04-05	Y170960040	747.0 ppb
2017-04-05	Y170960041	718.0 ppb
2017-04-05	Y170960042	580.0 ppb
2017-05-01	Y171240032	798.0 ppb
2017-05-01	Y171240033	726.0 ppb
2017-05-01	Y171240034	687.0 ppb
2017-06-05	Y171590139	570.0 ppb
2017-06-05	Y171590140	575.0 ppb
2017-06-05	Y171590141	651.0 ppb
2017-07-05	Y171870072	759.0 ppb
2017-07-05	Y171870073	710.0 ppb
2017-07-05	Y171870074	690.0 ppb
2017-08-02	Y172150046	868.0 ppb
2017-08-02	Y172150047	875.0 ppb
2017-08-02	Y172150048	826.0 ppb
2017-09-05	Y172500024	ND
2017-09-05	Y172500025	ND
2017-09-05	Y172500026	27.1 ppb
2017-10-02	Y172780011	396.0 ppb
2017-10-02	Y172780012	371.0 ppb
2017-10-02	Y172780013	670.0 ppb
2017-11-06	Y173130031	ND
2017-11-06	Y173130032	ND
2017-11-06	Y173130033	ND
2017-12-04	Y173410008	ND
2017-12-04	Y173410009	ND
2017-12-04	Y173410010	ND
2018-01-02	Y180040028	239.0 ppb
2018-01-02	Y180040029	268.0 ppb
2018-01-02	Y180040027	224.0 ppb
2018-02-05	Y180400024	ND
2018-02-05	Y180400023	404.0 ppb
2018-02-05	Y180400025	ND
2018-03-06	Y180670035	626.0 ppb
2018-03-06	Y180670034	328.0 ppb
2018-03-06	Y180670033	352.0 ppb
2018-04-02	Y180950028	489.0 ppb
2018-04-02	Y180950030	443.0 ppb
2018-04-02	Y180950029	546.0 ppb
2018-05-02	Y181240014	759.0 ppb
2018-05-02	Y181240015	571.0 ppb
2018-05-02	Y181240016	939.0 ppb
2018-06-05	Y181580005	ND
2018-06-05	Y181580007	23.9 ppb
2018-06-05	Y181580006	ND
2018-07-02	Y181860060	ND
2018-07-02	Y181860059	ND
2018-07-02	Y181860061	ND
2018-08-08	Y182210033	ND
2018-08-08	Y182210034	ND
2018-08-08	Y182210035	ND
2018-09-04	Y182500026	ND
2018-09-04	Y182500025	ND
2018-09-04	Y182500024	ND
2018-10-03	Y182780008	ND
2018-10-03	Y182780009	ND
2018-10-03	Y182780010	50.7 ppb
2018-11-05	Y183120057	ND
2018-11-05	Y183120058	392.0 ppb
2018-11-05	Y183120059	26.4 ppb
2018-12-04	Y183400033	ND
2018-12-04	Y183400034	389.0 ppb
2018-12-04	Y183400032	ND
2019-01-08	Y190100036	ND
2019-01-08	Y190100038	ND
2019-01-08	Y190100037	ND
2019-02-06	Y190380059	ND
2019-02-06	Y190380060	ND
2019-02-06	Y190380058	ND
2019-03-06	Y190660022	855.0 ppb
2019-03-06	Y190660023	837.0 ppb
2019-03-06	Y190660021	854.0 ppb
2019-04-03	Y190950014	550.0 ppb
2019-04-03	Y190950015	456.0 ppb
2019-04-03	Y190950013	664.0 ppb
2019-05-06	Y191290068	ND
2019-05-06	Y191290069	ND
2019-05-06	Y191290070	ND
2019-06-04	Y191570037	ND
2019-06-04	Y191570036	ND
2019-06-04	Y191570038	ND
2019-07-09	Y191920057	ND
2019-07-09	Y191920055	ND
2019-07-09	Y191920056	ND
2019-08-07	Y192210048	ND
2019-08-07	Y192210049	ND
2019-08-07	Y192210047	ND
2019-09-04	Y192490026	ND
2019-09-04	Y192490028	ND
2019-09-04	Y192490027	ND
2019-10-02	Y192770019	502.0 ppb
2019-10-02	Y192770018	493.0 ppb
2019-10-02	Y192770020	461.0 ppb
2019-11-05	Y193110025	ND
2019-11-05	Y193110026	57.6 ppb
2019-11-05	Y193110024	ND
2019-12-03	Y193390031	ND
2019-12-03	Y193390030	ND
2019-12-03	Y193390029	696.0 ppb