Chlorite

City of Stamford

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

210

Samples

Samples exceeding legal limit (MCL)

105

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Detections	Range of results
2014	79.1 ppb	33	11	ND - 499.0 ppb
2015	162.9 ppb	36	27	ND - 895.0 ppb
2016	95.3 ppb	36	25	ND - 737.0 ppb
2017	100.0 ppb	33	29	ND - 388.0 ppb
2018	153.7 ppb	36	26	ND - 861.0 ppb
2019	135.1 ppb	36	29	ND - 706.0 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
2014-01-22	1272422	ND
2014-01-22	1272420	ND
2014-01-22	1272421	ND
2014-02-12	1277102	ND
2014-02-12	1277103	188.0 ppb
2014-02-12	1277104	184.0 ppb
2014-03-12	1284565	ND
2014-03-12	1284562	ND
2014-03-12	1284566	ND
2014-04-16	1294126	ND
2014-04-16	1294128	ND
2014-04-16	1294127	ND
2014-06-18	1310970	ND
2014-06-18	1310969	ND
2014-06-18	1310971	ND
2014-07-23	1320129	ND
2014-07-23	1320131	ND
2014-07-23	1320130	ND
2014-08-27	1329719	ND
2014-08-27	1329721	ND
2014-08-27	1329720	ND
2014-09-24	1336964	ND
2014-09-24	1336966	ND
2014-09-24	1336965	ND
2014-10-23	1344443	210.0 ppb
2014-10-23	1344441	378.0 ppb
2014-10-23	1344442	82.6 ppb
2014-11-25	1353320	302.0 ppb
2014-11-25	1353324	187.0 ppb
2014-11-25	1353325	499.0 ppb
2014-12-18	1359028	157.0 ppb
2014-12-18	1359030	279.0 ppb
2014-12-18	1359029	145.0 ppb
2015-01-14	1364706	429.0 ppb
2015-01-14	1364708	680.0 ppb
2015-01-14	1364707	386.0 ppb
2015-02-11	1372084	188.0 ppb
2015-02-11	1372086	580.0 ppb
2015-02-11	1372085	208.0 ppb
2015-03-11	1378440	168.0 ppb
2015-03-11	1378441	147.0 ppb
2015-03-11	1378442	256.0 ppb
2015-04-21	1388976	ND
2015-04-21	1388974	ND
2015-04-21	1388975	ND
2015-05-20	1396828	ND
2015-05-20	1396827	ND
2015-05-20	1396826	49.4 ppb
2015-06-17	1403774	30.0 ppb
2015-06-17	1403775	66.4 ppb
2015-06-17	1403776	ND
2015-07-22	1412827	285.0 ppb
2015-07-27	1412835	15.7 ppb
2015-07-27	1412836	57.2 ppb
2015-08-20	1420964	14.7 ppb
2015-08-20	1420963	156.0 ppb
2015-08-20	1420962	224.0 ppb
2015-09-09	1425976	ND
2015-09-09	1425977	20.8 ppb
2015-09-09	1425975	20.7 ppb
2015-10-14	1435399	ND
2015-10-14	1435398	22.1 ppb
2015-10-14	1435397	ND
2015-11-11	1443377	359.0 ppb
2015-11-11	1443378	231.0 ppb
2015-11-11	1443376	181.0 ppb
2015-12-09	1450203	97.8 ppb
2015-12-09	1450202	895.0 ppb
2015-12-09	1450204	95.5 ppb
2016-01-13	1458366	737.0 ppb
2016-01-13	1458368	85.4 ppb
2016-01-13	1458367	18.5 ppb
2016-02-17	1468379	205.0 ppb
2016-02-17	1468381	ND
2016-02-17	1468380	231.0 ppb
2016-03-09	1473351	355.0 ppb
2016-03-09	1473353	35.1 ppb
2016-03-09	1473352	ND
2016-04-13	1482528	23.4 ppb
2016-04-13	1482526	254.0 ppb
2016-04-13	1482527	163.0 ppb
2016-05-11	1490786	85.0 ppb
2016-05-11	1490787	37.0 ppb
2016-05-11	1490785	320.0 ppb
2016-06-15	1499946	126.0 ppb
2016-06-15	1499948	ND
2016-06-15	1499947	ND
2016-07-13	1507061	ND
2016-07-13	1507059	86.4 ppb
2016-07-13	1507060	33.3 ppb
2016-08-10	1514962	75.8 ppb
2016-08-10	1514963	148.0 ppb
2016-08-10	1514964	79.5 ppb
2016-09-15	1525082	161.0 ppb
2016-09-15	1525083	50.3 ppb
2016-09-15	1525084	ND
2016-10-12	1532751	45.0 ppb
2016-10-12	1532756	ND
2016-10-12	1532755	ND
2016-11-09	1539848	12.0 ppb
2016-11-09	1539850	ND
2016-11-09	1539849	10.6 ppb
2016-12-07	1546604	55.1 ppb
2016-12-07	1546605	ND
2016-12-07	1546606	ND
2017-02-08	1562285	200.0 ppb
2017-02-08	1562286	321.0 ppb
2017-02-08	15692287	128.0 ppb
2017-03-08	1570197	53.7 ppb
2017-03-08	1570194	143.0 ppb
2017-03-08	1570196	124.0 ppb
2017-04-19	1581151	137.0 ppb
2017-04-19	1581149	388.0 ppb
2017-04-19	1581150	230.0 ppb
2017-05-10	1587204	331.0 ppb
2017-05-10	1587203	129.0 ppb
2017-05-10	1587205	26.4 ppb
2017-06-07	1594419	60.4 ppb
2017-06-07	1594418	140.0 ppb
2017-06-07	1594420	32.8 ppb
2017-07-05	1601323	56.9 ppb
2017-07-05	1601321	113.0 ppb
2017-07-05	1601322	229.0 ppb
2017-08-02	1609973	16.9 ppb
2017-08-02	1609975	ND
2017-08-02	1609974	ND
2017-09-06	1619660	ND
2017-09-06	1619659	8.09 ppb
2017-09-06	1619658	23.3 ppb
2017-10-11	1629449	48.7 ppb
2017-10-11	1629450	14.9 ppb
2017-10-11	1629448	40.3 ppb
2017-11-08	1636997	82.0 ppb
2017-11-08	1636998	ND
2017-11-08	1636999	90.4 ppb
2017-12-06	1644150	12.6 ppb
2017-12-06	1644148	42.0 ppb
2017-12-06	1644149	77.8 ppb
2018-01-10	1652723	84.3 ppb
2018-01-10	1652724	23.0 ppb
2018-01-10	1652725	85.2 ppb
2018-02-21	1663882	585.0 ppb
2018-02-21	1663887	584.0 ppb
2018-02-21	1663886	99.8 ppb
2018-03-14	1669154	861.0 ppb
2018-03-14	1669155	304.0 ppb
2018-03-14	1669156	461.0 ppb
2018-04-11	1676147	186.0 ppb
2018-04-11	1676146	318.0 ppb
2018-04-11	1676148	490.0 ppb
2018-05-03	1682045	97.2 ppb
2018-05-03	1682046	71.4 ppb
2018-05-03	1682044	218.0 ppb
2018-06-06	1690675	11.3 ppb
2018-06-06	1690673	49.0 ppb
2018-06-06	1690674	ND
2018-07-05	1698388	244.0 ppb
2018-07-05	1698389	ND
2018-07-05	1698390	ND
2018-08-01	1705639	56.9 ppb
2018-08-01	1705641	ND
2018-08-01	1705642	ND
2018-09-12	1716985	ND
2018-09-12	1716984	27.9 ppb
2018-09-12	1716983	89.5 ppb
2018-10-17	1727540	48.4 ppb
2018-10-17	1727537	106.0 ppb
2018-10-17	1727539	ND
2018-11-07	1733395	ND
2018-11-07	1733394	ND
2018-11-07	1733393	157.0 ppb
2018-12-12	1743054	ND
2018-12-12	1743055	63.0 ppb
2018-12-12	1743053	211.0 ppb
2019-01-09	1749581	706.0 ppb
2019-01-09	1749582	71.9 ppb
2019-01-09	1749583	237.0 ppb
2019-02-06	1757142	ND
2019-02-06	1757143	14.3 ppb
2019-02-06	1757144	ND
2019-03-06	1764673	96.7 ppb
2019-03-06	1764672	27.9 ppb
2019-03-06	1764671	123.0 ppb
2019-04-03	1772297	37.7 ppb
2019-04-03	1772298	40.4 ppb
2019-04-03	1772290	158.0 ppb
2019-05-02	1780487	94.2 ppb
2019-05-02	1780488	43.6 ppb
2019-05-02	1780486	314.0 ppb
2019-06-06	1789954	22.9 ppb
2019-06-06	1789953	28.4 ppb
2019-06-06	1789952	208.0 ppb
2019-07-25	1804728	ND
2019-07-25	1804726	497.0 ppb
2019-07-25	1804727	26.9 ppb
2019-08-01	1806420	ND
2019-08-01	1806418	383.0 ppb
2019-08-01	1806419	16.2 ppb
2019-09-05	1816848	ND
2019-09-05	1816847	332.0 ppb
2019-09-05	1816849	11.7 ppb
2019-10-03	1826195	556.0 ppb
2019-10-03	1826196	71.4 ppb
2019-10-03	1826197	103.0 ppb
2019-11-07	1836374	ND
2019-11-07	1836373	ND
2019-11-07	1836372	244.0 ppb
2019-12-05	1844497	338.0 ppb
2019-12-05	1844498	16.3 ppb
2019-12-05	1844499	43.9 ppb