Chloroform
Valencia Water Company
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.
Testing results - average by year
Year | Average result | Samples taken | Detections | Range of results |
---|---|---|---|---|
2013 | N/A | 0 | 0 | N/A |
2014 | 0.0611 ppb | 54 | 3 | ND - 1.10 ppb |
2015 | 0.153 ppb | 53 | 6 | ND - 1.70 ppb |
2016 | 0.552 ppb | 54 | 18 | ND - 3.50 ppb |
2017 | 1.25 ppb | 53 | 32 | ND - 3.60 ppb |
2018 | 1.78 ppb | 46 | 31 | ND - 5.20 ppb |
2019 | 2.20 ppb | 54 | 36 | ND - 8.10 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 |
---|---|---|
2014-01-13 | 9590-800-0850 | ND |
2014-01-13 | 9590-801-1005 | ND |
2014-01-13 | 9590-802-0916 | ND |
2014-01-13 | 9590-803-1135 | ND |
2014-01-13 | 9590-804-1335 | ND |
2014-01-13 | 9590-805-1315 | 1.10 ppb |
2014-01-13 | 9590-806-0945 | ND |
2014-01-13 | 9590-807-0805 | ND |
2014-02-26 | 9590-048-0915 | ND |
2014-04-14 | 9590-800-1120 | ND |
2014-04-14 | 9590-801-0928 | ND |
2014-04-14 | 9590-802-0810 | ND |
2014-04-14 | 9590-803-1320 | ND |
2014-04-14 | 9590-804-1100 | ND |
2014-04-14 | 9590-805-1335 | ND |
2014-04-14 | 9590-806-1015 | ND |
2014-04-14 | 9590-807-1130 | ND |
2014-05-28 | 9590-048-0915 | ND |
2014-07-14 | 9590-800-1300 | ND |
2014-07-14 | 9590-801-1100 | ND |
2014-07-14 | 9590-802-0815 | ND |
2014-07-14 | 9590-803-1315 | ND |
2014-07-14 | 9590-804-1230 | ND |
2014-07-14 | 9590-805-1345 | ND |
2014-07-14 | 9590-806-1000 | ND |
2014-07-14 | 9590-807-1410 | 1.10 ppb |
2014-08-28 | 9590-048-0940 | ND |
2014-10-13 | 9590-800-1100 | ND |
2014-10-13 | 9590-801-1400 | ND |
2014-10-13 | 9590-802-0900 | ND |
2014-10-13 | 9590-803-1400 | ND |
2014-10-13 | 9590-804-1455 | ND |
2014-10-13 | 9590-805-1415 | ND |
2014-10-13 | 9590-806-1300 | ND |
2014-10-13 | 9590-807-1545 | ND |
2014-11-08 | 9590-021-0830 | ND |
2014-11-08 | 9590-024-1135 | ND |
2014-11-08 | 9590-052-0930 | ND |
2014-11-08 | 9590-062-0815 | ND |
2014-11-13 | 9590-005-0950 | ND |
2014-11-13 | 9590-017-0940 | ND |
2014-11-13 | 9590-018-0900 | ND |
2014-11-13 | 9590-025-1050 | ND |
2014-11-13 | 9590-026-0845 | ND |
2014-11-13 | 9590-046-1100 | 1.10 ppb |
2014-11-13 | 9590-049-0900 | ND |
2014-11-13 | 9590-051-1010 | ND |
2014-11-13 | 9590-058-0920 | ND |
2014-11-13 | 9590-070-1025 | ND |
2014-11-20 | 9590-003-1115 | ND |
2014-11-20 | 9590-004-0930 | ND |
2014-11-20 | 9590-047-1030 | ND |
2014-11-20 | 9590-048-1015 | ND |
2014-11-20 | 9590-073-0915 | ND |
2015-01-12 | 9590-800-1040 | ND |
2015-01-12 | 9590-801-1130 | ND |
2015-01-12 | 9590-802-0840 | ND |
2015-01-12 | 9590-803-0910 | ND |
2015-01-12 | 9590-804-1120 | ND |
2015-01-12 | 9590-805-0950 | ND |
2015-01-12 | 9590-806-1100 | ND |
2015-01-12 | 9590-807-1340 | ND |
2015-02-19 | 9590-048-0950 | ND |
2015-04-13 | 9590-800-1330 | 1.70 ppb |
2015-04-13 | 9590-801-1450 | ND |
2015-04-13 | 9590-802-1400 | ND |
2015-04-13 | 9590-803-1030 | ND |
2015-04-13 | 9590-804-1310 | 1.50 ppb |
2015-04-13 | 9590-805-0940 | ND |
2015-04-13 | 9590-806-1345 | ND |
2015-04-13 | 9590-807-1420 | ND |
2015-06-04 | 9590-048-1000 | ND |
2015-07-13 | 9590-800-1311 | ND |
2015-07-13 | 9590-801-1345 | ND |
2015-07-13 | 9590-802-1245 | ND |
2015-07-13 | 9590-803-1331 | ND |
2015-07-13 | 9590-804-1302 | ND |
2015-07-13 | 9590-805-1350 | ND |
2015-07-13 | 9590-806-1330 | ND |
2015-07-13 | 9590-807-1235 | ND |
2015-08-27 | 9590-048-0918 | ND |
2015-10-12 | 9590-800-1135 | 1.10 ppb |
2015-10-12 | 9590-801-0930 | 1.40 ppb |
2015-10-12 | 9590-802-0838 | 1.30 ppb |
2015-10-12 | 9590-803-1315 | ND |
2015-10-12 | 9590-804-0936 | ND |
2015-10-12 | 9590-805-1307 | ND |
2015-10-12 | 9590-806-1006 | 1.10 ppb |
2015-10-12 | 9590-807-0750 | ND |
2015-11-05 | 9590-005-0932 | ND |
2015-11-05 | 9590-018-0951 | ND |
2015-11-05 | 9590-021-0815 | ND |
2015-11-05 | 9590-024-0854 | ND |
2015-11-05 | 9590-026-0910 | ND |
2015-11-05 | 9590-058-1012 | ND |
2015-11-05 | 9590-062-0828 | ND |
2015-11-12 | 9590-017-0950 | ND |
2015-11-12 | 9590-025-0818 | ND |
2015-11-12 | 9590-046-0907 | ND |
2015-11-12 | 9590-049-0932 | ND |
2015-11-12 | 9590-051-1015 | ND |
2015-11-12 | 9590-070-0838 | ND |
2015-11-30 | 9590-003-0903 | ND |
2015-11-30 | 9590-004-1014 | ND |
2015-11-30 | 9590-047-1006 | ND |
2015-11-30 | 9590-048-0920 | ND |
2015-11-30 | 9590-073-0845 | ND |
2016-01-11 | 9590-800-0900 | ND |
2016-01-11 | 9590-801-1010 | 1.10 ppb |
2016-01-11 | 9590-802-1050 | ND |
2016-01-11 | 9590-803-1310 | ND |
2016-01-11 | 9590-804-1400 | ND |
2016-01-11 | 9590-805-1330 | ND |
2016-01-11 | 9590-806-0940 | ND |
2016-01-11 | 9590-807-1110 | ND |
2016-02-25 | 9590-048-0928 | ND |
2016-03-03 | 9590-052-0910 | ND |
2016-04-18 | 9590-800-0928 | ND |
2016-04-18 | 9590-801-1040 | 2.10 ppb |
2016-04-18 | 9590-802-1100 | 1.40 ppb |
2016-04-18 | 9590-803-1255 | 1.50 ppb |
2016-04-18 | 9590-804-1345 | 1.10 ppb |
2016-04-18 | 9590-805-1320 | ND |
2016-04-18 | 9590-806-1010 | 1.20 ppb |
2016-04-18 | 9590-807-1120 | ND |
2016-05-26 | 9590-048-0959 | ND |
2016-07-18 | 9590-800-1012 | 1.20 ppb |
2016-07-18 | 9590-801-0858 | ND |
2016-07-18 | 9590-802-0830 | 1.000 ppb |
2016-07-18 | 9590-803-1042 | ND |
2016-07-18 | 9590-804-0919 | 1.30 ppb |
2016-07-18 | 9590-805-1120 | ND |
2016-07-18 | 9590-806-0924 | 1.000 ppb |
2016-07-18 | 9590-807-0810 | ND |
2016-10-17 | 9590-800-0910 | 2.10 ppb |
2016-10-17 | 9590-801-1000 | 2.00 ppb |
2016-10-17 | 9590-802-0835 | 1.40 ppb |
2016-10-17 | 9590-803-1130 | 2.60 ppb |
2016-10-17 | 9590-804-1100 | 3.50 ppb |
2016-10-17 | 9590-805-1145 | 1.50 ppb |
2016-10-17 | 9590-806-0935 | 2.00 ppb |
2016-10-17 | 9590-807-1025 | ND |
2016-11-03 | 9590-005-1000 | ND |
2016-11-03 | 9590-018-1030 | ND |
2016-11-03 | 9590-021-0820 | ND |
2016-11-03 | 9590-024-0940 | ND |
2016-11-03 | 9590-026-0950 | ND |
2016-11-03 | 9590-052-0920 | ND |
2016-11-03 | 9590-058-1040 | ND |
2016-11-03 | 9590-062-0900 | ND |
2016-11-09 | 9590-017-1036 | ND |
2016-11-09 | 9590-025-0926 | ND |
2016-11-09 | 9590-046-1007 | 1.80 ppb |
2016-11-09 | 9590-049-0910 | ND |
2016-11-09 | 9590-051-1054 | ND |
2016-11-09 | 9590-070-0943 | ND |
2016-11-17 | 9590-003-0922 | ND |
2016-11-17 | 9590-004-0954 | ND |
2016-11-17 | 9590-047-0943 | ND |
2016-11-17 | 9590-048-1006 | ND |
2016-11-17 | 9590-073-0903 | ND |
2017-01-17 | 9590-800-1015 | 2.00 ppb |
2017-01-17 | 9590-801-1045 | 3.40 ppb |
2017-01-17 | 9590-802-1100 | 3.60 ppb |
2017-01-17 | 9590-803-0930 | 2.10 ppb |
2017-01-17 | 9590-805-0945 | 1.20 ppb |
2017-01-17 | 9590-806-1030 | 2.80 ppb |
2017-01-17 | 9590-807-0835 | 1.40 ppb |
2017-02-23 | 9590-048-0948 | ND |
2017-04-17 | 9590-800-1000 | 2.00 ppb |
2017-04-17 | 9590-801-1040 | 1.70 ppb |
2017-04-17 | 9590-802-1055 | 1.90 ppb |
2017-04-17 | 9590-803-0915 | 1.70 ppb |
2017-04-17 | 9590-804-1130 | 1.80 ppb |
2017-04-17 | 9590-805-0935 | 1.80 ppb |
2017-04-17 | 9590-806-1020 | 2.00 ppb |
2017-04-17 | 9590-807-1110 | 1.80 ppb |
2017-07-18 | 9590-800-0905 | 1.90 ppb |
2017-07-18 | 9590-801-0935 | 2.30 ppb |
2017-07-18 | 9590-802-0955 | 1.20 ppb |
2017-07-18 | 9590-803-1045 | 3.40 ppb |
2017-07-18 | 9590-804-1020 | 2.60 ppb |
2017-07-18 | 9590-805-1100 | 3.30 ppb |
2017-07-18 | 9590-806-0920 | 1.30 ppb |
2017-07-18 | 9590-807-0835 | 1.30 ppb |
2017-08-24 | 9590-048-0915 | ND |
2017-10-16 | 9590-800-1005 | 1.50 ppb |
2017-10-16 | 9590-801-1030 | 2.50 ppb |
2017-10-16 | 9590-802-0950 | 1.70 ppb |
2017-10-16 | 9590-803-1125 | 3.10 ppb |
2017-10-16 | 9590-804-1100 | 1.80 ppb |
2017-10-16 | 9590-805-1130 | 2.00 ppb |
2017-10-16 | 9590-806-1015 | 1.80 ppb |
2017-10-16 | 9590-807-1045 | ND |
2017-10-26 | 9590-048-0900 | ND |
2017-11-02 | 9590-005-1005 | ND |
2017-11-02 | 9590-018-0940 | ND |
2017-11-02 | 9590-021-0855 | ND |
2017-11-02 | 9590-024-1020 | ND |
2017-11-02 | 9590-026-1215 | ND |
2017-11-02 | 9590-052-0920 | ND |
2017-11-02 | 9590-058-0955 | ND |
2017-11-02 | 9590-062-0905 | ND |
2017-11-16 | 9590-017-1130 | ND |
2017-11-16 | 9590-025-1010 | ND |
2017-11-16 | 9590-046-1030 | 1.60 ppb |
2017-11-16 | 9590-049-1115 | ND |
2017-11-16 | 9590-051-1150 | ND |
2017-11-16 | 9590-070-1050 | ND |
2017-11-30 | 9590-003-1000 | ND |
2017-11-30 | 9590-004-0900 | ND |
2017-11-30 | 9590-047-0850 | 1.50 ppb |
2017-11-30 | 9590-048-0945 | ND |
2017-11-30 | 9590-073-0920 | ND |
2018-01-16 | 9590-800-0903 | 2.40 ppb |
2018-01-16 | 9590-801-0932 | 2.40 ppb |
2018-01-16 | 9590-802-0945 | 2.50 ppb |
2018-01-16 | 9590-803-0826 | 1.90 ppb |
2018-01-16 | 9590-804-1021 | 2.60 ppb |
2018-01-16 | 9590-805-0840 | ND |
2018-01-16 | 9590-806-0917 | 1.90 ppb |
2018-01-16 | 9590-807-1000 | ND |
2018-04-16 | 9590-800-0840 | 3.50 ppb |
2018-04-16 | 9590-801-0905 | 5.20 ppb |
2018-04-16 | 9590-802-0925 | 2.90 ppb |
2018-04-16 | 9590-803-0810 | 4.60 ppb |
2018-04-16 | 9590-804-1005 | 1.70 ppb |
2018-04-16 | 9590-805-0820 | 3.50 ppb |
2018-04-16 | 9590-806-0855 | 2.40 ppb |
2018-04-16 | 9590-807-0945 | 2.00 ppb |
2018-07-16 | 9590-800-0845 | 2.80 ppb |
2018-07-16 | 9590-801-0925 | 2.70 ppb |
2018-07-16 | 9590-802-0945 | 1.80 ppb |
2018-07-16 | 9590-803-0810 | 4.50 ppb |
2018-07-16 | 9590-804-1020 | 2.60 ppb |
2018-07-16 | 9590-806-0905 | 1.90 ppb |
2018-07-16 | 9590-807-1000 | 1.40 ppb |
2018-07-26 | 9590-805-1636 | 1.50 ppb |
2018-10-15 | 9590-800-0835 | 2.90 ppb |
2018-10-15 | 9590-801-0800 | 3.70 ppb |
2018-10-15 | 9590-802-0850 | 2.80 ppb |
2018-10-15 | 9590-803-0945 | 3.10 ppb |
2018-10-15 | 9590-804-1110 | 2.20 ppb |
2018-10-15 | 9590-805-0920 | 1.70 ppb |
2018-10-15 | 9590-806-0815 | 2.70 ppb |
2018-10-15 | 9590-807-1135 | 1.90 ppb |
2018-11-07 | 2104-005-0923 | ND |
2018-11-07 | 2104-018-0941 | ND |
2018-11-07 | 2104-021-0830 | ND |
2018-11-07 | 2104-025-0857 | ND |
2018-11-07 | 2104-026-0909 | ND |
2018-11-07 | 2104-052-0910 | ND |
2018-11-07 | 2104-058-0954 | ND |
2018-11-07 | 2104-062-0845 | ND |
2018-11-14 | 2104-017-1005 | ND |
2018-11-14 | 2104-025-0940 | ND |
2018-11-14 | 2104-046-0855 | 2.40 ppb |
2018-11-14 | 2104-049-0950 | ND |
2018-11-14 | 2104-051-1030 | ND |
2018-11-14 | 2104-070-0920 | ND |
2019-01-14 | 9590-800-0910 | 3.00 ppb |
2019-01-14 | 9590-801-1000 | 4.90 ppb |
2019-01-14 | 9590-802-1015 | 2.30 ppb |
2019-01-14 | 9590-803-0835 | 3.90 ppb |
2019-01-14 | 9590-804-1100 | 1.50 ppb |
2019-01-14 | 9590-805-0845 | 2.10 ppb |
2019-01-14 | 9590-806-0935 | 3.10 ppb |
2019-01-14 | 9590-807-1030 | 1.50 ppb |
2019-02-12 | 2104-003-0900 | ND |
2019-02-12 | 2104-004-0830 | ND |
2019-02-12 | 2104-047-0840 | 1.10 ppb |
2019-02-12 | 2104-073-0950 | ND |
2019-04-15 | 9590-800-0935 | 6.10 ppb |
2019-04-15 | 9590-801-1020 | 5.90 ppb |
2019-04-15 | 9590-802-1040 | 5.40 ppb |
2019-04-15 | 9590-803-0840 | 7.70 ppb |
2019-04-15 | 9590-804-1125 | 4.70 ppb |
2019-04-15 | 9590-805-0900 | 8.10 ppb |
2019-04-15 | 9590-806-1000 | 6.10 ppb |
2019-04-15 | 9590-807-1100 | 6.30 ppb |
2019-07-15 | 9590-800-0920 | 2.00 ppb |
2019-07-15 | 9590-801-1030 | 1.60 ppb |
2019-07-15 | 9590-802-1050 | 1.70 ppb |
2019-07-15 | 9590-803-0835 | 2.60 ppb |
2019-07-15 | 9590-804-1200 | 1.30 ppb |
2019-07-15 | 9590-805-0900 | 1.90 ppb |
2019-07-15 | 9590-806-0955 | 2.00 ppb |
2019-07-15 | 9590-807-1125 | 1.90 ppb |
2019-10-14 | 9590-800-1125 | 3.40 ppb |
2019-10-14 | 9590-801-0815 | 3.10 ppb |
2019-10-14 | 9590-802-0835 | 3.60 ppb |
2019-10-14 | 9590-803-1040 | 3.90 ppb |
2019-10-14 | 9590-804-0935 | 2.00 ppb |
2019-10-14 | 9590-805-1100 | 2.40 ppb |
2019-10-14 | 9590-806-1210 | 3.30 ppb |
2019-10-14 | 9590-807-0905 | 1.10 ppb |
2019-11-06 | 2104-018-0825 | ND |
2019-11-06 | 2104-021-0926 | ND |
2019-11-06 | 2104-026-0900 | ND |
2019-11-06 | 2104-052-0840 | ND |
2019-11-06 | 2104-058-1000 | ND |
2019-11-06 | 2104-062-0908 | ND |
2019-11-14 | 2104-017-1100 | ND |
2019-11-14 | 2104-025-0935 | ND |
2019-11-14 | 2104-046-0840 | 2.70 ppb |
2019-11-14 | 2104-049-0915 | ND |
2019-11-14 | 2104-051-0940 | ND |
2019-11-14 | 2104-070-0920 | ND |
2019-11-20 | 2104-003-0900 | ND |
2019-11-20 | 2104-004-0940 | 1.20 ppb |
2019-11-20 | 2104-047-0920 | 3.50 ppb |
2019-11-20 | 2104-073-0930 | ND |
2019-11-21 | 9590-048-1120 | ND |
2019-11-25 | 2104-005-1030 | ND |