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EWG's Tap Water Database — 2019 UPDATE

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Arsenic

Los Angeles Department of Water and Power

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.

 

366

Samples

0

Samples exceeding legal limit (MCL)

198

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20122.16 ppb6134ND - 6.40 ppb
20131.43 ppb6128ND - 5.10 ppb
20141.50 ppb6026ND - 5.40 ppb
20151.20 ppb6029ND - 3.60 ppb
20162.93 ppb6345ND - 7.60 ppb
20172.07 ppb6136ND - 5.70 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
2012-01-041200-011-07152.10 ppb
2012-01-111200-011-0835ND
2012-01-181200-011-09552.00 ppb
2012-01-181200-205-1200ND
2012-01-251200-011-1210ND
2012-02-011200-011-0920ND
2012-02-021200-133-1000ND
2012-02-081200-011-1000ND
2012-02-141200-011-10202.40 ppb
2012-02-151200-011-08552.40 ppb
2012-02-221200-011-09502.90 ppb
2012-02-291200-011-09202.60 ppb
2012-03-071200-011-0825ND
2012-03-141200-011-0825ND
2012-03-211200-011-0845ND
2012-03-281200-011-1100ND
2012-04-041200-011-1015ND
2012-04-111200-011-0800ND
2012-04-181200-011-0735ND
2012-04-251200-011-1045ND
2012-05-021200-011-1120ND
2012-05-091200-011-1015ND
2012-05-161200-011-1030ND
2012-05-171200-011-0900ND
2012-05-221200-133-1045ND
2012-05-231200-011-10452.20 ppb
2012-05-301200-011-11152.40 ppb
2012-06-061200-011-09252.60 ppb
2012-06-131200-011-10202.60 ppb
2012-06-201200-011-09503.20 ppb
2012-06-271200-011-10103.70 ppb
2012-07-041200-011-11053.50 ppb
2012-07-111200-011-08554.20 ppb
2012-07-181200-011-10154.20 ppb
2012-07-251200-011-11204.10 ppb
2012-08-011200-011-09454.50 ppb
2012-08-081200-011-10005.20 ppb
2012-08-141200-011-12006.20 ppb
2012-08-141200-133-10302.20 ppb
2012-08-151200-011-09306.10 ppb
2012-08-221200-011-10304.30 ppb
2012-08-291200-011-11455.40 ppb
2012-09-051200-011-08355.50 ppb
2012-09-121200-011-09205.50 ppb
2012-09-191200-011-08254.50 ppb
2012-09-261200-011-09304.60 ppb
2012-10-031200-011-08052.20 ppb
2012-10-101200-011-1245ND
2012-10-171200-011-1200ND
2012-10-241200-011-1240ND
2012-10-311200-011-1135ND
2012-11-071200-011-1130ND
2012-11-131200-011-1035ND
2012-11-131200-133-0840ND
2012-11-141200-011-1015ND
2012-11-211200-011-09302.30 ppb
2012-11-281200-011-10154.30 ppb
2012-12-051200-011-09204.20 ppb
2012-12-121200-011-11055.10 ppb
2012-12-191200-011-08306.10 ppb
2012-12-261200-011-10356.40 ppb
2013-01-021200-011-10004.90 ppb
2013-01-091200-011-0845ND
2013-01-161200-011-1000ND
2013-01-231200-011-0850ND
2013-01-301200-011-0935ND
2013-02-071200-011-0720ND
2013-02-131200-011-0910ND
2013-02-201200-011-0805ND
2013-02-201200-133-1200ND
2013-02-271200-011-11452.10 ppb
2013-03-061200-011-1045ND
2013-03-131200-011-10352.10 ppb
2013-03-201200-011-1050ND
2013-03-201200-011-1100ND
2013-03-271200-011-1220ND
2013-04-031200-011-0905ND
2013-04-101200-011-0745ND
2013-04-171200-011-0825ND
2013-04-241200-011-1110ND
2013-05-011200-011-0820ND
2013-05-081200-011-0740ND
2013-05-091200-011-1025ND
2013-05-091200-133-0825ND
2013-05-151200-011-0835ND
2013-05-221200-011-1100ND
2013-05-291200-011-1245ND
2013-06-051200-011-0820ND
2013-06-121200-011-0905ND
2013-06-191200-011-10002.00 ppb
2013-06-261200-011-13402.00 ppb
2013-07-021200-011-09052.00 ppb
2013-07-091200-011-08302.20 ppb
2013-07-161200-011-11252.60 ppb
2013-07-231200-011-08402.60 ppb
2013-07-301200-011-11153.10 ppb
2013-08-061200-011-11403.50 ppb
2013-08-131200-011-12154.30 ppb
2013-08-131200-011-12354.60 ppb
2013-08-131200-133-10402.20 ppb
2013-08-201200-011-12002.00 ppb
2013-08-271200-011-0910ND
2013-09-031200-011-12003.70 ppb
2013-09-101200-011-11003.90 ppb
2013-09-171200-011-10153.90 ppb
2013-09-241200-011-10453.80 ppb
2013-10-011200-011-10403.50 ppb
2013-10-081200-011-11303.90 ppb
2013-10-151200-011-09453.40 ppb
2013-10-221200-011-09402.50 ppb
2013-10-291200-011-10202.80 ppb
2013-11-051200-011-09005.10 ppb
2013-11-121200-011-0915ND
2013-11-191200-011-0900ND
2013-11-191200-011-1045ND
2013-11-191200-133-0800ND
2013-11-261200-011-1045ND
2013-12-031200-011-0825ND
2013-12-101200-011-0850ND
2013-12-171200-011-10103.50 ppb
2013-12-241200-011-07002.50 ppb
2013-12-311200-011-10102.30 ppb
2014-01-071200-011-10252.20 ppb
2014-01-141200-011-10152.60 ppb
2014-01-211200-011-09352.50 ppb
2014-01-281200-011-08452.50 ppb
2014-02-041200-011-08102.40 ppb
2014-02-111200-011-1030ND
2014-02-181200-011-08302.10 ppb
2014-02-251200-011-0830ND
2014-02-261200-011-1215ND
2014-02-261200-133-1215ND
2014-03-041200-011-09105.10 ppb
2014-03-111200-011-08454.20 ppb
2014-03-181200-011-10352.10 ppb
2014-03-271200-011-0835ND
2014-04-011200-011-0850ND
2014-04-081200-011-10152.40 ppb
2014-04-151200-011-1015ND
2014-04-221200-011-1035ND
2014-04-291200-011-09402.20 ppb
2014-05-061200-011-10052.10 ppb
2014-05-131200-011-1025ND
2014-05-141200-011-1115ND
2014-05-141200-133-1105ND
2014-05-201200-011-1035ND
2014-05-271200-011-0955ND
2014-06-031200-011-0805ND
2014-06-101200-011-0745ND
2014-06-171200-011-0840ND
2014-06-241200-011-0810ND
2014-07-011200-011-0810ND
2014-07-081200-011-08252.10 ppb
2014-07-151200-011-09154.20 ppb
2014-07-221200-011-10104.30 ppb
2014-07-291200-011-10453.90 ppb
2014-08-051200-011-10003.90 ppb
2014-08-121200-011-10154.60 ppb
2014-08-121200-011-10304.60 ppb
2014-08-191200-011-12154.40 ppb
2014-08-201200-133-0900ND
2014-08-261200-011-07204.50 ppb
2014-09-021200-011-09155.10 ppb
2014-09-091200-011-10255.10 ppb
2014-09-161200-011-07505.40 ppb
2014-09-231200-011-08303.20 ppb
2014-09-301200-011-08052.50 ppb
2014-10-071200-011-1045ND
2014-10-141200-011-1200ND
2014-10-211200-011-1100ND
2014-10-281200-011-1100ND
2014-11-041200-011-1030ND
2014-11-111200-011-0915ND
2014-11-121200-011-1240ND
2014-11-181200-011-1015ND
2014-11-181200-133-0935ND
2014-11-251200-011-1050ND
2014-12-021200-011-1005ND
2014-12-091200-011-1055ND
2014-12-161200-011-0815ND
2014-12-231200-011-1255ND
2014-12-301200-011-0745ND
2015-01-061200-011-0750ND
2015-01-131200-011-08052.50 ppb
2015-01-201200-011-07503.50 ppb
2015-01-221200-205-11252.50 ppb
2015-01-271200-011-07552.40 ppb
2015-01-281200-205-1230ND
2015-02-031200-011-1120ND
2015-02-041200-205-1010ND
2015-02-101200-011-1010ND
2015-02-111200-133-0825ND
2015-02-111200-205-1150ND
2015-02-171200-011-1050ND
2015-02-191200-011-0845ND
2015-02-241200-011-1055ND
2015-03-031200-011-07402.20 ppb
2015-03-101200-011-1120ND
2015-03-171200-011-08152.10 ppb
2015-03-241200-011-1215ND
2015-03-311200-011-0810ND
2015-04-071200-011-1010ND
2015-04-141200-011-1040ND
2015-04-211200-011-0950ND
2015-04-281200-011-1035ND
2015-05-051200-011-1130ND
2015-05-121200-011-1125ND
2015-05-191200-011-0900ND
2015-05-191200-011-1050ND
2015-05-191200-133-1100ND
2015-05-261200-011-1120ND
2015-06-021200-011-1215ND
2015-06-091200-011-1115ND
2015-06-161200-011-1200ND
2015-06-231200-011-10452.10 ppb
2015-06-301200-011-1105ND
2015-08-041200-011-10402.20 ppb
2015-08-041200-011-10452.30 ppb
2015-08-041200-133-0645ND
2015-08-111200-011-10152.20 ppb
2015-08-181200-011-07252.30 ppb
2015-08-251200-011-10402.90 ppb
2015-09-011200-011-10252.70 ppb
2015-09-081200-011-10452.90 ppb
2015-09-151200-011-08002.40 ppb
2015-09-221200-011-12352.70 ppb
2015-09-291200-011-12252.50 ppb
2015-10-061200-011-11402.10 ppb
2015-10-131200-011-10002.40 ppb
2015-10-201200-011-0755ND
2015-10-201200-205-1155ND
2015-10-271200-011-09102.20 ppb
2015-11-031200-011-09002.30 ppb
2015-11-051200-011-10052.30 ppb
2015-11-051200-133-0755ND
2015-11-101200-011-11152.20 ppb
2015-11-171200-011-09502.10 ppb
2015-11-241200-011-07352.80 ppb
2015-12-011200-011-10452.20 ppb
2015-12-151200-011-11402.50 ppb
2015-12-221200-011-12002.70 ppb
2015-12-291200-011-11003.60 ppb
2016-01-051200-011-11453.60 ppb
2016-01-121200-011-11503.40 ppb
2016-01-191200-011-09003.20 ppb
2016-01-261200-011-11052.30 ppb
2016-02-021200-011-11302.60 ppb
2016-02-091200-011-11502.60 ppb
2016-02-091200-133-0930ND
2016-02-161200-011-07352.40 ppb
2016-02-231200-011-1050ND
2016-02-241200-011-1215ND
2016-03-011200-011-1125ND
2016-03-081200-011-0725ND
2016-03-151200-011-09402.00 ppb
2016-03-221200-011-1120ND
2016-03-291200-011-1015ND
2016-04-051200-011-09553.30 ppb
2016-04-121200-011-09405.10 ppb
2016-04-191200-011-10252.70 ppb
2016-04-261200-011-10202.50 ppb
2016-05-031200-011-10252.80 ppb
2016-05-101200-011-08302.90 ppb
2016-05-171200-011-12053.00 ppb
2016-05-241200-011-12253.60 ppb
2016-05-251200-011-11353.60 ppb
2016-05-251200-133-1210ND
2016-05-311200-011-10453.30 ppb
2016-05-311200-133-1045ND
2016-06-071200-011-12303.90 ppb
2016-06-141200-011-11155.00 ppb
2016-06-211200-011-09205.50 ppb
2016-06-281200-011-13006.60 ppb
2016-07-051200-011-07106.50 ppb
2016-07-121200-011-08407.40 ppb
2016-07-191200-011-11307.60 ppb
2016-07-211200-205-12256.50 ppb
2016-07-261200-011-12455.90 ppb
2016-07-291200-205-07405.90 ppb
2016-07-301200-205-09005.10 ppb
2016-08-021200-011-08455.10 ppb
2016-08-091200-011-12106.00 ppb
2016-08-161200-011-09555.00 ppb
2016-08-171200-011-10104.80 ppb
2016-08-231200-011-10455.40 ppb
2016-08-231200-133-10052.50 ppb
2016-08-301200-011-08454.90 ppb
2016-09-061200-011-09304.80 ppb
2016-09-131200-011-09454.90 ppb
2016-09-201200-011-11154.50 ppb
2016-09-271200-011-11204.70 ppb
2016-10-041200-011-07452.00 ppb
2016-10-111200-011-0950ND
2016-10-181200-011-0935ND
2016-10-251200-011-12302.10 ppb
2016-11-011200-011-10002.00 ppb
2016-11-091200-011-10352.00 ppb
2016-11-151200-011-1130ND
2016-11-211200-133-1115ND
2016-11-221200-011-1215ND
2016-11-291200-011-0845ND
2016-12-061200-011-1145ND
2016-12-131200-011-1200ND
2016-12-201200-011-1045ND
2016-12-271200-011-12352.80 ppb
2017-01-031200-011-13254.20 ppb
2017-01-101200-011-12202.40 ppb
2017-01-171200-011-12252.40 ppb
2017-01-241200-011-1240ND
2017-01-311200-011-1230ND
2017-02-071200-011-09002.40 ppb
2017-02-141200-011-11403.80 ppb
2017-02-211200-011-11403.60 ppb
2017-02-211200-011-12003.60 ppb
2017-02-211200-133-12102.60 ppb
2017-02-281200-011-12003.40 ppb
2017-03-071200-011-11453.60 ppb
2017-03-141200-011-11343.80 ppb
2017-03-211200-011-11294.00 ppb
2017-03-281200-011-11015.10 ppb
2017-04-041200-011-11185.70 ppb
2017-04-111200-011-12245.40 ppb
2017-04-181200-011-11495.60 ppb
2017-04-251200-011-12195.00 ppb
2017-05-021200-011-08174.30 ppb
2017-05-091200-011-07454.00 ppb
2017-05-091200-011-09404.00 ppb
2017-05-161200-011-10303.00 ppb
2017-05-171200-133-09413.40 ppb
2017-05-231200-011-07442.70 ppb
2017-05-301200-011-08082.20 ppb
2017-06-061200-011-0740ND
2017-06-131200-011-10572.20 ppb
2017-06-201200-011-1101ND
2017-06-271200-011-0732ND
2017-07-041200-011-1044ND
2017-07-111200-011-0727ND
2017-07-121200-205-1000ND
2017-07-181200-011-0739ND
2017-07-251200-011-1055ND
2017-08-011200-011-1127ND
2017-08-011200-133-0940ND
2017-08-081200-011-1150ND
2017-08-151200-011-1040ND
2017-08-211200-011-1010ND
2017-08-221200-011-1100ND
2017-08-291200-011-12222.30 ppb
2017-09-051200-011-13123.10 ppb
2017-09-121200-011-13143.50 ppb
2017-09-191200-011-13203.20 ppb
2017-09-261200-011-13223.70 ppb
2017-10-031200-011-12573.50 ppb
2017-10-101200-011-12554.10 ppb
2017-10-171200-011-13063.60 ppb
2017-10-241200-011-07503.10 ppb
2017-10-311200-011-13082.00 ppb
2017-11-071200-011-0959ND
2017-11-141200-011-1132ND
2017-11-201200-011-1000ND
2017-11-201200-133-10402.00 ppb
2017-11-211200-011-1154ND
2017-11-281200-011-1248ND
2017-12-051200-011-1227ND
2017-12-121200-011-0947ND
2017-12-191200-011-0841ND
2017-12-261200-011-1224ND