Arsenic

Suez

Arsenic is a potent carcinogen and common contaminant in drinking water. Arsenic causes thousands of cases of cancer each year in the U.S. Click here to read more about arsenic.

MORE ABOUT THIS CONTAMINANT

251

Samples

Samples exceeding legal limit (MCL)

149

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Detections	Range of results
2014	2.18 ppb	62	25	ND - 9.00 ppb
2015	2.47 ppb	30	17	ND - 8.00 ppb
2016	4.00 ppb	21	18	ND - 9.80 ppb
2017	2.72 ppb	81	48	ND - 15.0 ppb
2018	2.88 ppb	27	16	ND - 17.0 ppb
2019	4.40 ppb	30	25	ND - 18.0 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.004 ppb

The EWG Health Guideline of 0.004 ppb for arsenic 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 cancer.

EPA Maximum Contaminant
Level (MCL) 10 ppb

The legal limit for arsenic, established in 2001, was based on costs for arsenic removal, as calculated at the time that the standard was set. This limit does not fully protect against the risk of cancer due to arsenic exposure.

ppb = parts per billion

All test results

Date	Lab ID	Result
2014-03-04	I1407725	6.00 ppb
2014-03-04	I1407732	ND
2014-03-04	I1407718	ND
2014-03-04	I1407728	6.00 ppb
2014-03-04	I1407727	ND
2014-03-04	I1407726	5.00 ppb
2014-03-04	I1407731	ND
2014-03-04	I1407730	3.00 ppb
2014-03-04	I1407735	3.00 ppb
2014-06-06	I1420556	ND
2014-06-06	I1420554	ND
2014-06-06	I1420560	ND
2014-06-06	I1420558	ND
2014-06-06	I1420559	6.00 ppb
2014-06-09	I1420777	ND
2014-06-09	I1420778	ND
2014-06-09	I1420783	5.00 ppb
2014-06-09	I1420776	8.00 ppb
2014-06-09	I1420779	8.00 ppb
2014-06-09	I1420781	6.00 ppb
2014-06-09	I1420774	7.00 ppb
2014-06-09	I1420782	4.00 ppb
2014-06-09	I1420772	ND
2014-06-10	I1421072	ND
2014-06-10	I1421073	4.00 ppb
2014-06-10	I1421071	ND
2014-06-10	I1421075	ND
2014-06-10	I1421074	ND
2014-06-12	I1421492	ND
2014-06-12	I1421498	ND
2014-06-12	I1421497	ND
2014-06-12	I1421494	ND
2014-06-17	I1422335	ND
2014-06-17	I1422330	ND
2014-06-26	I1423785	ND
2014-06-27	I1424004	ND
2014-07-01	I1424564	ND
2014-07-01	I1424561	ND
2014-07-01	I1424560	5.00 ppb
2014-07-01	I1424565	6.00 ppb
2014-07-08	I1425431	ND
2014-07-08	I1425428	ND
2014-07-16	I1427068	ND
2014-07-16	I1427071	6.00 ppb
2014-07-16	I1427069	9.00 ppb
2014-07-16	I1427058	ND
2014-07-16	I1427070	4.00 ppb
2014-07-16	I1427064	5.00 ppb
2014-07-17	I1427228	ND
2014-07-30	I1429113	ND
2014-07-30	I1429112	ND
2014-07-30	I1429111	ND
2014-07-30	1429110	ND
2014-08-05	I1429865	ND
2014-08-05	I1429867	4.00 ppb
2014-08-05	I1429864	4.00 ppb
2014-08-11	I	ND
2014-08-11	I1430896	ND
2014-08-19	I1432288	7.00 ppb
2014-08-19	I1432287	4.00 ppb
2014-08-19	I1432283	6.00 ppb
2014-10-02	I1439118	4.00 ppb
2015-03-09	I1508860	ND
2015-03-09	I1508865	ND
2015-03-12	I1509544	ND
2015-05-27	I1520479	ND
2015-05-28	I1520653	ND
2015-06-04	I1521791	ND
2015-06-04	I1521779	ND
2015-06-09	I1522532	5.00 ppb
2015-06-09	I1522529	ND
2015-06-09	I1522527	4.00 ppb
2015-06-16	I1523454	ND
2015-06-16	I1523455	ND
2015-06-24	I1525295	4.00 ppb
2015-06-24	I1525294	ND
2015-06-24	I1525296	4.00 ppb
2015-06-24	I1525301	3.00 ppb
2015-06-24	I1525293	8.00 ppb
2015-07-15	I1528683	4.00 ppb
2015-07-15	I1528681	6.00 ppb
2015-07-15	I1528669	ND
2015-07-15	I1528680	3.00 ppb
2015-07-15	I1528682	6.00 ppb
2015-07-17	I1529095	3.00 ppb
2015-07-17	N1529093	3.00 ppb
2015-07-22	I1529742	ND
2015-07-22	I1529750	4.00 ppb
2015-07-23	I1530007	4.00 ppb
2015-07-24	I1530230	3.00 ppb
2015-08-06	I1532698	6.00 ppb
2015-12-03	I1551970	4.00 ppb
2016-06-23	I1627647	3.00 ppb
2016-06-24	I1627840	ND
2016-06-24	I1627839	4.10 ppb
2016-06-27	I1628126	4.10 ppb
2016-06-27	I1628124	2.70 ppb
2016-06-27	I1628125	4.20 ppb
2016-06-27	I1628127	5.00 ppb
2016-06-28	I1628440	2.10 ppb
2016-06-28	I1628441	ND
2016-06-29	I1628655	3.70 ppb
2016-06-29	I1628654	3.10 ppb
2016-06-29	I1628657	ND
2016-06-29	I1628653	8.60 ppb
2016-07-07	I1629728	2.40 ppb
2016-07-15	I1631434	5.90 ppb
2016-08-03	I1634934	4.30 ppb
2016-08-03	I1634932	9.80 ppb
2016-08-15	I1636772	7.40 ppb
2016-08-15	I1636773	4.70 ppb
2016-08-25	I1638555	3.50 ppb
2016-10-03	I1645230	5.50 ppb
2017-03-13	I1709899	4.30 ppb
2017-03-13	I1709900	4.90 ppb
2017-03-13	I1709901	ND
2017-03-14	I1710137	ND
2017-03-14	I1710138	ND
2017-03-14	I1710138	ND
2017-03-14	I1710134	2.20 ppb
2017-03-14	I1710137	ND
2017-03-14	I1710140	ND
2017-03-14	I1710135	ND
2017-05-30	I1722581	2.40 ppb
2017-05-30	I1722579	2.30 ppb
2017-05-30	I1722574	ND
2017-05-31	I1722760	8.30 ppb
2017-05-31	I1722755	4.50 ppb
2017-05-31	I1722752	ND
2017-05-31	I1722751	ND
2017-05-31	I1722753	ND
2017-05-31	I1722759	4.40 ppb
2017-05-31	I1722763	ND
2017-05-31	I1722762	5.30 ppb
2017-05-31	I1722761	ND
2017-05-31	I1722758	6.20 ppb
2017-06-06	I1723655	6.60 ppb
2017-06-06	I1723654	ND
2017-06-06	I1723657	4.00 ppb
2017-06-06	I1723656	2.70 ppb
2017-06-19	I1726111	3.00 ppb
2017-06-19	I1726107	3.30 ppb
2017-06-19	I1726108	ND
2017-06-19	I1726109	ND
2017-06-21	I1726722	ND
2017-06-21	I1726774	2.20 ppb
2017-06-21	I1726775	ND
2017-06-21	I1726776	4.70 ppb
2017-06-21	I1726777	ND
2017-06-21	I1726779	2.50 ppb
2017-06-21	I1726781	ND
2017-06-21	I1726782	ND
2017-06-21	I1726771	2.50 ppb
2017-06-22	I1726960	ND
2017-06-22	I1726962	ND
2017-06-22	I1726966	4.20 ppb
2017-06-22	I1726964	12.0 ppb
2017-06-26	I1727441	ND
2017-06-26	I1727439	3.00 ppb
2017-07-10	I1729868	3.60 ppb
2017-07-10	I1729875	15.0 ppb
2017-07-10	I1729876	2.60 ppb
2017-07-10	I1729877	3.90 ppb
2017-07-10	I1729867	8.20 ppb
2017-07-11	I1730135	ND
2017-07-11	I1730137	ND
2017-07-13	I1730788	11.0 ppb
2017-07-13	I1730789	4.50 ppb
2017-07-13	I1730790	3.00 ppb
2017-07-17	I1731306	ND
2017-07-17	I1731309	7.40 ppb
2017-07-19	I1731943	6.40 ppb
2017-07-20	I1732221	6.30 ppb
2017-07-20	I1732214	2.10 ppb
2017-07-20	I1732217	5.80 ppb
2017-07-20	I1732215	3.10 ppb
2017-07-25	I1732814	2.60 ppb
2017-07-25	I1732818	7.00 ppb
2017-07-25	I1732811	3.80 ppb
2017-07-25	I1732813	ND
2017-08-01	I1734083	3.20 ppb
2017-08-03	I1734570	ND
2017-08-03	I1734567	ND
2017-08-03	I1734565	ND
2017-08-04	I1734727	2.40 ppb
2017-08-07	I1735103	2.80 ppb
2017-08-14	I1736475	ND
2017-08-14	I1736476	3.30 ppb
2017-08-14	I1736477	4.70 ppb
2017-08-17	I1737329	2.80 ppb
2017-08-18	I1737572	3.30 ppb
2017-08-22	I1738034	3.60 ppb
2017-09-26	I1744547	2.10 ppb
2017-10-24	I1749574	ND
2018-02-01	I1804597	ND
2018-02-05	I1804986	ND
2018-02-06	I1805280	ND
2018-02-12	I1806151	ND
2018-02-12	I1806152	7.20 ppb
2018-03-12	I1810541	17.0 ppb
2018-05-15	I1821863	2.50 ppb
2018-05-15	I1821851	ND
2018-05-23	I1823164	ND
2018-06-06	I1825586	3.40 ppb
2018-06-06	I1825584	5.40 ppb
2018-06-06	I1825583	5.10 ppb
2018-06-06	I1825581	ND
2018-06-21	I1828646	4.00 ppb
2018-06-21	I1828604	ND
2018-06-21	I1828603	ND
2018-06-21	I1828606	4.60 ppb
2018-06-21	I1828608	3.00 ppb
2018-06-26	I1829342	ND
2018-06-26	I1829345	2.20 ppb
2018-06-26	I1829341	ND
2018-07-02	I1830675	3.90 ppb
2018-07-02	I1830578	5.50 ppb
2018-07-10	I1832042	4.50 ppb
2018-07-10	I1832044	2.60 ppb
2018-07-18	I1833964	2.60 ppb
2018-08-15	I1839829	4.20 ppb
2019-02-19	I1907390	3.70 ppb
2019-02-19	I1907388	3.10 ppb
2019-02-19	I1907386	ND
2019-03-06	I1909865	3.90 ppb
2019-03-06	I1909868	3.10 ppb
2019-03-13	I1911210	2.30 ppb
2019-03-27	I1913515	2.50 ppb
2019-04-17	I1917321	6.40 ppb
2019-04-18	I1917715	2.90 ppb
2019-04-18	I1917718	2.40 ppb
2019-06-12	I1927972	ND
2019-06-13	I1928243	4.40 ppb
2019-07-03	I1932118	5.80 ppb
2019-07-03	I1932258	7.00 ppb
2019-07-09	I1933033	4.40 ppb
2019-07-09	I1933034	5.10 ppb
2019-07-10	I1933346	ND
2019-07-10	I1933345	ND
2019-07-10	I1933341	3.60 ppb
2019-07-16	I1934434	18.0 ppb
2019-07-19	I1935267	ND
2019-07-19	I1935266	4.10 ppb
2019-07-23	I1935756	6.20 ppb
2019-07-31	I1937498	7.30 ppb
2019-08-28	I1942930	14.0 ppb
2019-08-28	I1942932	4.00 ppb
2019-09-05	I1944523	8.70 ppb
2019-10-02	I1949691	2.90 ppb
2019-10-09	I1951015	3.70 ppb
2019-10-09	I1951013	2.40 ppb