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EWG's Tap Water Database — 2021 UPDATE

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Chloroform

California Water Service Company - Hermosa / Redondo Beach

Chloroform, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Chloroform and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Read More.

In addition to tap water disinfection, chloroform pollution in the environment also comes from industrial discharges from pulp and paper mills, and from urban wastewater effluent. Human studies show that chloroform damages the kidneys, liver and central nervous system. In animals, chloroform causes infertility, birth defects and cancer.

Click here to read more about disinfection byproducts.

MORE ABOUT THIS CONTAMINANT

 

205

Samples

0

Samples exceeding legal limit (MCL)

188

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
201410.9 ppb3432ND - 20.0 ppb
201510.7 ppb3432ND - 19.9 ppb
20167.77 ppb3432ND - 14.4 ppb
201710.2 ppb3332ND - 26.0 ppb
20183.75 ppb3628ND - 9.06 ppb
20193.61 ppb3432ND - 8.49 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.4 ppb

The EWG Health Guideline of 0.4 ppb for chloroform was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.

ppb = parts per billion

All test results

Date Lab ID Result
2014-03-045701-800-115110.2 ppb
2014-03-045701-801-09189.81 ppb
2014-03-045701-802-090711.1 ppb
2014-03-045701-803-14176.93 ppb
2014-03-045701-804-08467.95 ppb
2014-03-045701-805-150110.8 ppb
2014-03-045701-806-10339.74 ppb
2014-03-045701-807-142610.8 ppb
2014-06-035701-800-123813.6 ppb
2014-06-035701-801-094415.7 ppb
2014-06-035701-802-093314.0 ppb
2014-06-035701-803-14353.50 ppb
2014-06-035701-804-091013.4 ppb
2014-06-035701-805-152313.4 ppb
2014-06-035701-806-104912.6 ppb
2014-06-035701-807-14451.12 ppb
2014-06-255701-005-0925ND
2014-09-025701-800-130018.8 ppb
2014-09-025701-801-102520.0 ppb
2014-09-025701-802-101019.3 ppb
2014-09-025701-803-15003.19 ppb
2014-09-025701-804-094017.9 ppb
2014-09-025701-805-152518.6 ppb
2014-09-025701-806-113019.2 ppb
2014-09-025701-807-14451.16 ppb
2014-09-035701-001-1450ND
2014-12-025701-800-133212.1 ppb
2014-12-025701-801-104812.1 ppb
2014-12-025701-802-103411.9 ppb
2014-12-025701-803-14246.53 ppb
2014-12-025701-804-101012.6 ppb
2014-12-025701-805-10179.21 ppb
2014-12-025701-806-133813.2 ppb
2014-12-025701-807-13209.59 ppb
2015-03-035701-800-065510.4 ppb
2015-03-035701-801-065510.6 ppb
2015-03-035701-802-065510.5 ppb
2015-03-035701-803-06556.34 ppb
2015-03-035701-804-065510.0 ppb
2015-03-035701-805-065510.2 ppb
2015-03-035701-806-065510.7 ppb
2015-03-035701-807-06559.33 ppb
2015-06-025701-800-065314.2 ppb
2015-06-025701-801-065314.7 ppb
2015-06-025701-802-065314.2 ppb
2015-06-025701-803-065312.1 ppb
2015-06-025701-804-065314.6 ppb
2015-06-025701-805-065314.1 ppb
2015-06-025701-806-065314.8 ppb
2015-06-025701-807-06532.25 ppb
2015-06-175701-005-0950ND
2015-08-265701-001-1210ND
2015-09-085701-800-081317.5 ppb
2015-09-085701-801-081318.1 ppb
2015-09-085701-802-081318.3 ppb
2015-09-085701-803-081310.9 ppb
2015-09-085701-804-081318.0 ppb
2015-09-085701-805-081318.4 ppb
2015-09-085701-806-081319.9 ppb
2015-09-085701-807-08130.920 ppb
2015-12-085701-800-08108.63 ppb
2015-12-085701-801-08109.27 ppb
2015-12-085701-802-08109.42 ppb
2015-12-085810-803-14547.70 ppb
2015-12-085701-804-08107.55 ppb
2015-12-085810-805-15348.80 ppb
2015-12-085810-806-11259.10 ppb
2015-12-085810-807-15041.50 ppb
2016-03-085701-800-09203.14 ppb
2016-03-085701-801-09202.95 ppb
2016-03-085701-802-09203.65 ppb
2016-03-085701-803-09202.14 ppb
2016-03-085701-804-09202.65 ppb
2016-03-085701-805-09202.59 ppb
2016-03-085701-806-09202.67 ppb
2016-03-085701-807-09202.45 ppb
2016-06-075701-800-091911.2 ppb
2016-06-075701-801-091912.4 ppb
2016-06-075701-802-091911.0 ppb
2016-06-075701-803-09197.18 ppb
2016-06-075701-804-091911.8 ppb
2016-06-075701-805-091910.2 ppb
2016-06-075701-806-091913.4 ppb
2016-06-075701-807-09197.28 ppb
2016-06-215701-005-1300ND
2016-08-179590-001-1010ND
2016-09-065701-800-063513.3 ppb
2016-09-065701-801-063513.7 ppb
2016-09-065701-802-063513.6 ppb
2016-09-065701-803-06358.26 ppb
2016-09-065701-804-063513.3 ppb
2016-09-065701-805-063514.4 ppb
2016-09-065701-806-063514.3 ppb
2016-09-065701-807-063511.6 ppb
2016-12-065701-800-08387.26 ppb
2016-12-065701-801-08388.38 ppb
2016-12-065701-802-08388.01 ppb
2016-12-065701-803-08383.08 ppb
2016-12-065701-804-08389.25 ppb
2016-12-065701-805-08386.64 ppb
2016-12-065701-806-08388.60 ppb
2016-12-065701-807-08383.76 ppb
2017-03-075810-800-134614.0 ppb
2017-03-075810-802-102520.0 ppb
2017-03-075810-803-15295.40 ppb
2017-03-075810-804-100423.0 ppb
2017-03-075810-805-155212.0 ppb
2017-03-075810-806-114718.0 ppb
2017-03-075810-807-16006.50 ppb
2017-03-085810-801-000020.0 ppb
2017-06-065701-800-091110.6 ppb
2017-06-065701-801-091112.5 ppb
2017-06-065701-802-091112.3 ppb
2017-06-065701-803-09111.02 ppb
2017-06-065701-804-091110.00 ppb
2017-06-065701-805-09116.66 ppb
2017-06-065701-806-091114.4 ppb
2017-06-065701-807-09111.12 ppb
2017-06-215701-005-1330ND
2017-09-055701-800-08589.49 ppb
2017-09-055701-801-085812.3 ppb
2017-09-055701-802-08587.57 ppb
2017-09-055701-803-08585.13 ppb
2017-09-055701-804-085817.4 ppb
2017-09-055701-805-08587.82 ppb
2017-09-055701-806-085811.7 ppb
2017-09-055701-807-08584.11 ppb
2017-12-065810-800-10206.50 ppb
2017-12-065810-801-09505.40 ppb
2017-12-065810-802-09405.10 ppb
2017-12-065810-803-112010.00 ppb
2017-12-065810-804-09205.10 ppb
2017-12-065810-805-115512.0 ppb
2017-12-065810-806-10054.40 ppb
2017-12-065810-807-113526.0 ppb
2018-01-165810-807-14362.60 ppb
2018-03-065701-800-08483.39 ppb
2018-03-065701-801-0848ND
2018-03-065701-802-08484.29 ppb
2018-03-065701-803-0848ND
2018-03-065701-804-08484.39 ppb
2018-03-065701-805-0848ND
2018-03-065701-806-0848ND
2018-03-065701-807-0848ND
2018-06-055701-800-08145.64 ppb
2018-06-055701-801-08145.05 ppb
2018-06-055701-802-08144.69 ppb
2018-06-055701-803-08142.73 ppb
2018-06-055701-804-08144.98 ppb
2018-06-055701-805-08145.08 ppb
2018-06-055701-806-08145.05 ppb
2018-06-055701-807-08143.06 ppb
2018-06-215701-005-1015ND
2018-07-279590-001-0935ND
2018-09-045701-800-12387.30 ppb
2018-09-045701-801-09538.02 ppb
2018-09-045701-802-09449.06 ppb
2018-09-045701-803-14403.41 ppb
2018-09-045701-804-09136.72 ppb
2018-09-045701-805-15246.54 ppb
2018-09-045701-806-10587.12 ppb
2018-09-045701-807-14486.26 ppb
2018-12-045701-800-07093.97 ppb
2018-12-045701-801-07094.71 ppb
2018-12-045701-802-07093.91 ppb
2018-12-045701-803-07092.54 ppb
2018-12-045701-804-07094.82 ppb
2018-12-045701-805-07093.25 ppb
2018-12-045701-806-07094.24 ppb
2018-12-045701-807-07092.31 ppb
2018-12-209590-005-1245ND
2019-03-055701-800-09064.72 ppb
2019-03-055701-801-09065.13 ppb
2019-03-055701-802-09065.52 ppb
2019-03-055701-803-09063.68 ppb
2019-03-055701-804-09065.04 ppb
2019-03-055701-805-09064.37 ppb
2019-03-055701-806-09065.40 ppb
2019-03-055701-807-09064.66 ppb
2019-06-045701-800-09293.31 ppb
2019-06-045701-801-09298.49 ppb
2019-06-045701-802-09298.35 ppb
2019-06-045701-803-09293.43 ppb
2019-06-045701-804-09297.20 ppb
2019-06-045701-805-09293.70 ppb
2019-06-045701-806-09296.87 ppb
2019-06-045701-807-09293.93 ppb
2019-09-035701-800-12233.25 ppb
2019-09-035701-801-10323.47 ppb
2019-09-035701-802-10213.44 ppb
2019-09-035701-803-14310.970 ppb
2019-09-035701-804-09583.34 ppb
2019-09-035701-805-15362.79 ppb
2019-09-035701-806-11373.88 ppb
2019-09-035701-807-14481.09 ppb
2019-12-035701-800-11312.74 ppb
2019-12-035701-801-10001.90 ppb
2019-12-035701-802-09512.15 ppb
2019-12-035701-803-13191.57 ppb
2019-12-035701-804-09291.95 ppb
2019-12-035701-805-14092.51 ppb
2019-12-035701-806-10422.15 ppb
2019-12-035701-807-13421.79 ppb
2019-12-269590-001-1300ND
2019-12-279590-005-1105ND