Chloroform
El Dorado ID - Main
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 | 56.4 ppb | 33 | 33 | 36.0 ppb - 92.0 ppb |
2015 | 56.8 ppb | 33 | 33 | 32.0 ppb - 84.0 ppb |
2016 | 54.1 ppb | 37 | 34 | ND - 92.0 ppb |
2017 | 55.1 ppb | 31 | 31 | 33.0 ppb - 80.0 ppb |
2018 | 44.8 ppb | 42 | 42 | 29.0 ppb - 83.0 ppb |
2019 | 41.3 ppb | 74 | 71 | ND - 73.0 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 |
---|---|---|
2014-02-03 | 9590-004-1020 | 36.0 ppb |
2014-02-11 | 9590-901-1039 | 72.0 ppb |
2014-02-11 | 9590-902-1345 | 59.0 ppb |
2014-02-11 | 9590-903-0916 | 54.0 ppb |
2014-02-11 | 9590-905-1215 | 53.0 ppb |
2014-02-11 | 9590-907-0920 | 53.0 ppb |
2014-02-11 | 9590-908-1220 | 53.0 ppb |
2014-02-11 | 9590-909-1050 | 52.0 ppb |
2014-02-11 | 9590-910-1010 | 50.0 ppb |
2014-05-13 | 9590-907-0920 | 57.0 ppb |
2014-05-13 | 9590-908-1330 | 64.0 ppb |
2014-05-13 | 9590-909-1200 | 80.0 ppb |
2014-05-13 | 9590-910-1010 | 62.0 ppb |
2014-05-14 | 9590-901-1116 | 83.0 ppb |
2014-05-14 | 9590-902-1500 | 83.0 ppb |
2014-05-14 | 9590-903-0950 | 71.0 ppb |
2014-05-14 | 9590-905-1310 | 92.0 ppb |
2014-08-13 | 9590-907-0925 | 43.0 ppb |
2014-08-13 | 9590-908-1325 | 49.0 ppb |
2014-08-13 | 9590-909-1225 | 49.0 ppb |
2014-08-13 | 9590-910-1015 | 51.0 ppb |
2014-08-15 | 9590-901-1105 | 66.0 ppb |
2014-08-15 | 9590-902-1420 | 58.0 ppb |
2014-08-15 | 9590-903-0940 | 40.0 ppb |
2014-08-15 | 9590-905-1305 | 60.0 ppb |
2014-11-10 | 9590-901-1025 | 41.0 ppb |
2014-11-10 | 9590-902-1330 | 50.0 ppb |
2014-11-10 | 9590-903-0920 | 40.0 ppb |
2014-11-10 | 9590-905-1205 | 49.0 ppb |
2014-11-14 | 9590-907-1305 | 41.0 ppb |
2014-11-14 | 9590-908-1345 | 55.0 ppb |
2014-11-14 | 9590-909-1150 | 57.0 ppb |
2014-11-14 | 9590-910-0900 | 39.0 ppb |
2015-02-10 | 9590-901-1107 | 51.0 ppb |
2015-02-10 | 9590-902-1417 | 51.0 ppb |
2015-02-10 | 9590-903-0920 | 44.0 ppb |
2015-02-10 | 9590-905-1249 | 44.0 ppb |
2015-02-11 | 9590-907-0910 | 58.0 ppb |
2015-02-11 | 9590-908-1320 | 63.0 ppb |
2015-02-11 | 9590-909-1035 | 82.0 ppb |
2015-02-11 | 9590-910-1000 | 59.0 ppb |
2015-05-07 | 9590-910-0920 | 48.0 ppb |
2015-05-12 | 9590-901-1025 | 77.0 ppb |
2015-05-12 | 9590-902-1420 | 72.0 ppb |
2015-05-12 | 9590-903-0902 | 58.0 ppb |
2015-05-12 | 9590-905-1235 | 78.0 ppb |
2015-05-12 | 9590-907-0920 | 60.0 ppb |
2015-05-12 | 9590-908-1305 | 66.0 ppb |
2015-05-12 | 9590-909-1050 | 84.0 ppb |
2015-05-12 | 9590-910-1005 | 64.0 ppb |
2015-08-10 | 9590-901-0945 | 43.0 ppb |
2015-08-10 | 9590-902-1350 | 52.0 ppb |
2015-08-10 | 9590-903-0815 | 32.0 ppb |
2015-08-10 | 9590-905-1200 | 51.0 ppb |
2015-08-14 | 9590-907-0750 | 35.0 ppb |
2015-08-14 | 9590-908-1340 | 37.0 ppb |
2015-08-14 | 9590-909-1255 | 54.0 ppb |
2015-08-14 | 9590-910-1200 | 34.0 ppb |
2015-11-09 | 9590-901-1020 | 79.0 ppb |
2015-11-09 | 9590-902-1340 | 58.0 ppb |
2015-11-09 | 9590-903-0915 | 59.0 ppb |
2015-11-09 | 9590-905-1210 | 50.0 ppb |
2015-11-09 | 9590-907-0845 | 50.0 ppb |
2015-11-09 | 9590-908-1050 | 72.0 ppb |
2015-11-09 | 9590-909-1010 | 58.0 ppb |
2015-11-09 | 9590-910-0930 | 51.0 ppb |
2016-02-09 | 9590-905-1300 | 70.0 ppb |
2016-02-09 | 9590-907-0930 | 53.0 ppb |
2016-02-09 | 9590-908-1230 | 73.0 ppb |
2016-02-09 | 9590-909-1150 | 92.0 ppb |
2016-02-09 | 9590-910-1015 | 60.0 ppb |
2016-02-10 | 9590-901-1020 | 73.0 ppb |
2016-02-10 | 9590-902-1250 | 72.0 ppb |
2016-02-10 | 9590-903-0910 | 65.0 ppb |
2016-05-12 | 9590-905-1310 | 55.0 ppb |
2016-05-12 | 9590-907-0900 | 48.0 ppb |
2016-05-12 | 9590-908-1105 | 70.0 ppb |
2016-05-12 | 9590-909-1025 | 10.00 ppb |
2016-05-12 | 9590-910-0945 | 46.0 ppb |
2016-05-13 | 9590-901-1048 | 58.0 ppb |
2016-05-13 | 9590-902-1318 | 51.0 ppb |
2016-05-13 | 9590-903-0940 | 39.0 ppb |
2016-07-12 | 9590-002-1100 | ND |
2016-07-21 | 9590-003-0945 | ND |
2016-07-21 | 9590-004-1240 | ND |
2016-08-09 | 9590-907-0945 | 50.0 ppb |
2016-08-09 | 9590-908-1405 | 55.0 ppb |
2016-08-09 | 9590-909-1120 | 73.0 ppb |
2016-08-09 | 9590-910-1045 | 51.0 ppb |
2016-08-11 | 9590-905-1315 | 64.0 ppb |
2016-08-12 | 9590-901-1055 | 44.0 ppb |
2016-08-12 | 9590-902-1255 | 54.0 ppb |
2016-08-12 | 9590-903-0950 | 41.0 ppb |
2016-09-13 | 9590-909-1300 | 59.0 ppb |
2016-09-26 | 9590-909-1335 | 71.0 ppb |
2016-11-08 | 9590-901-1010 | 51.0 ppb |
2016-11-08 | 9590-902-1148 | 58.0 ppb |
2016-11-08 | 9590-903-0900 | 44.0 ppb |
2016-11-08 | 9590-907-0952 | 49.0 ppb |
2016-11-08 | 9590-908-1330 | 81.0 ppb |
2016-11-08 | 9590-909-1120 | 88.0 ppb |
2016-11-08 | 9590-910-1035 | 80.0 ppb |
2016-11-10 | 9590-905-1145 | 54.0 ppb |
2017-02-07 | 9590-901-1045 | 58.0 ppb |
2017-02-07 | 9590-903-0940 | 45.0 ppb |
2017-02-07 | 9590-905-1340 | 51.0 ppb |
2017-02-08 | 9590-902-0945 | 78.0 ppb |
2017-02-08 | 9590-907-1045 | 63.0 ppb |
2017-02-08 | 9590-908-1158 | 70.0 ppb |
2017-02-08 | 9590-909-1135 | 77.0 ppb |
2017-02-08 | 9590-910-1115 | 58.0 ppb |
2017-05-08 | 9590-901-1125 | 57.0 ppb |
2017-05-08 | 9590-903-1420 | 46.0 ppb |
2017-05-08 | 9590-905-1320 | 58.0 ppb |
2017-05-09 | 9590-907-0915 | 47.0 ppb |
2017-05-09 | 9590-908-1150 | 60.0 ppb |
2017-05-09 | 9590-909-1035 | 70.0 ppb |
2017-05-09 | 9590-910-0955 | 44.0 ppb |
2017-08-07 | 9590-901-1030 | 50.0 ppb |
2017-08-07 | 9590-902-1400 | 53.0 ppb |
2017-08-07 | 9590-903-0900 | 39.0 ppb |
2017-08-07 | 9590-905-1240 | 57.0 ppb |
2017-08-08 | 9590-907-0945 | 39.0 ppb |
2017-08-08 | 9590-908-1300 | 58.0 ppb |
2017-08-08 | 9590-909-1150 | 64.0 ppb |
2017-08-08 | 9590-910-1030 | 44.0 ppb |
2017-11-07 | 9590-901-1030 | 46.0 ppb |
2017-11-07 | 9590-903-0915 | 33.0 ppb |
2017-11-07 | 9590-905-1205 | 48.0 ppb |
2017-11-08 | 9590-902-1355 | 56.0 ppb |
2017-11-08 | 9590-907-0945 | 44.0 ppb |
2017-11-08 | 9590-908-1445 | 60.0 ppb |
2017-11-08 | 9590-909-1410 | 80.0 ppb |
2017-11-08 | 9590-910-1330 | 56.0 ppb |
2018-02-12 | 9590-901-1045 | 83.0 ppb |
2018-02-12 | 9590-902-1335 | 44.0 ppb |
2018-02-12 | 9590-903-0925 | 48.0 ppb |
2018-02-12 | 9590-905-1235 | 39.0 ppb |
2018-02-13 | 9590-907-0920 | 35.0 ppb |
2018-02-13 | 9590-908-1225 | 41.0 ppb |
2018-02-13 | 9590-909-1050 | 48.0 ppb |
2018-02-13 | 9590-910-1002 | 35.0 ppb |
2018-05-07 | 9590-901-1250 | 65.0 ppb |
2018-05-07 | 9590-903-1415 | 47.0 ppb |
2018-05-07 | 9590-905-1043 | 63.0 ppb |
2018-05-07 | 9590-907-1515 | 56.0 ppb |
2018-05-08 | 9590-909-1250 | 66.0 ppb |
2018-05-08 | 9590-910-1330 | 50.0 ppb |
2018-05-09 | 9590-902-1320 | 55.0 ppb |
2018-05-09 | 9590-908-0925 | 49.0 ppb |
2018-08-13 | 9590-901-1135 | 33.0 ppb |
2018-08-13 | 9590-902-1435 | 40.0 ppb |
2018-08-13 | 9590-903-1010 | 30.0 ppb |
2018-08-13 | 9590-905-1315 | 46.0 ppb |
2018-08-14 | 9590-907-0910 | 36.0 ppb |
2018-08-14 | 9590-908-1220 | 41.0 ppb |
2018-08-14 | 9590-909-1030 | 51.0 ppb |
2018-08-14 | 9590-910-0950 | 38.0 ppb |
2018-10-30 | 9590-901-1010 | 34.0 ppb |
2018-10-30 | 9590-902-1325 | 43.0 ppb |
2018-10-30 | 9590-903-0855 | 30.0 ppb |
2018-10-30 | 9590-905-1135 | 42.0 ppb |
2018-10-30 | 9590-907-1430 | 36.0 ppb |
2018-11-13 | 9590-907-0915 | 31.0 ppb |
2018-11-13 | 9590-908-1227 | 39.0 ppb |
2018-11-13 | 9590-909-1010 | 44.0 ppb |
2018-11-13 | 9590-910-1150 | 36.0 ppb |
2018-11-14 | 9590-901-1035 | 31.0 ppb |
2018-11-14 | 9590-902-1418 | 38.0 ppb |
2018-11-14 | 9590-903-0920 | 29.0 ppb |
2018-11-14 | 9590-905-1205 | 40.0 ppb |
2018-12-11 | 9590-901-1000 | 68.0 ppb |
2018-12-11 | 9590-902-1450 | 56.0 ppb |
2018-12-11 | 9590-903-0840 | 48.0 ppb |
2018-12-11 | 9590-905-1335 | 56.0 ppb |
2018-12-12 | 9590-907-0912 | 42.0 ppb |
2019-01-08 | 9590-901-1050 | 64.0 ppb |
2019-01-08 | 9590-902-1415 | 48.0 ppb |
2019-01-08 | 9590-903-0930 | 38.0 ppb |
2019-01-08 | 9590-905-1210 | 47.0 ppb |
2019-01-08 | 9590-907-1510 | 38.0 ppb |
2019-02-15 | 9590-901-1100 | 53.0 ppb |
2019-02-15 | 9590-902-1315 | 55.0 ppb |
2019-02-15 | 9590-903-0930 | 46.0 ppb |
2019-02-15 | 9590-907-0920 | 46.0 ppb |
2019-02-15 | 9590-908-1220 | 69.0 ppb |
2019-02-15 | 9590-909-1012 | 73.0 ppb |
2019-02-15 | 9590-910-1138 | 64.0 ppb |
2019-03-13 | 9590-901-1020 | 47.0 ppb |
2019-03-13 | 9590-902-1350 | 45.0 ppb |
2019-03-13 | 9590-903-0900 | 36.0 ppb |
2019-03-13 | 9590-905-1150 | 38.0 ppb |
2019-03-13 | 9590-907-1445 | 39.0 ppb |
2019-04-09 | 9590-901-1020 | 55.0 ppb |
2019-04-09 | 9590-902-1315 | 56.0 ppb |
2019-04-09 | 9590-903-0905 | 47.0 ppb |
2019-04-09 | 9590-905-1125 | 58.0 ppb |
2019-04-09 | 9590-907-1420 | 50.0 ppb |
2019-05-14 | 9590-901-1050 | 47.0 ppb |
2019-05-14 | 9590-902-1355 | 45.0 ppb |
2019-05-14 | 9590-903-0910 | 40.0 ppb |
2019-05-14 | 9590-905-1200 | 69.0 ppb |
2019-05-14 | 9590-907-0912 | 37.0 ppb |
2019-05-14 | 9590-908-1300 | 45.0 ppb |
2019-05-14 | 9590-909-1035 | 48.0 ppb |
2019-05-14 | 9590-910-1210 | 41.0 ppb |
2019-06-11 | 9590-901-1010 | 39.0 ppb |
2019-06-11 | 9590-902-1252 | 41.0 ppb |
2019-06-11 | 9590-903-0850 | 34.0 ppb |
2019-06-11 | 9590-905-1115 | 72.0 ppb |
2019-06-11 | 9590-907-1347 | 34.0 ppb |
2019-07-02 | 9590-003-0915 | ND |
2019-07-02 | 9590-004-1200 | ND |
2019-07-09 | 9590-901-1035 | 38.0 ppb |
2019-07-09 | 9590-902-1410 | 39.0 ppb |
2019-07-09 | 9590-903-0905 | 34.0 ppb |
2019-07-09 | 9590-905-1205 | 66.0 ppb |
2019-07-09 | 9590-907-1512 | 35.0 ppb |
2019-07-16 | 9590-002-1000 | ND |
2019-08-13 | 9590-901-1035 | 37.0 ppb |
2019-08-13 | 9590-902-1350 | 43.0 ppb |
2019-08-13 | 9590-903-0915 | 33.0 ppb |
2019-08-13 | 9590-905-1150 | 50.0 ppb |
2019-08-13 | 9590-907-0940 | 36.0 ppb |
2019-08-13 | 9590-908-1245 | 46.0 ppb |
2019-08-13 | 9590-909-1030 | 42.0 ppb |
2019-08-13 | 9590-910-1215 | 38.0 ppb |
2019-09-10 | 9590-901-1105 | 21.0 ppb |
2019-09-10 | 9590-902-1355 | 27.0 ppb |
2019-09-10 | 9590-903-0930 | 33.0 ppb |
2019-09-10 | 9590-905-1220 | 44.0 ppb |
2019-09-10 | 9590-907-1500 | 20.0 ppb |
2019-10-08 | 9590-901-1045 | 33.0 ppb |
2019-10-08 | 9590-902-1345 | 39.0 ppb |
2019-10-08 | 9590-903-0920 | 25.0 ppb |
2019-10-08 | 9590-905-1200 | 34.0 ppb |
2019-10-08 | 9590-907-1450 | 31.0 ppb |
2019-11-12 | 9590-901-1040 | 34.0 ppb |
2019-11-12 | 9590-902-1355 | 49.0 ppb |
2019-11-12 | 9590-903-0915 | 29.0 ppb |
2019-11-12 | 9590-905-1205 | 36.0 ppb |
2019-11-12 | 9590-907-1505 | 33.0 ppb |
2019-11-12 | 9590-908-1200 | 45.0 ppb |
2019-11-12 | 9590-909-1015 | 54.0 ppb |
2019-11-12 | 9590-910-1130 | 52.0 ppb |
2019-12-10 | 9590-901-1015 | 31.0 ppb |
2019-12-10 | 9590-902-1350 | 43.0 ppb |
2019-12-10 | 9590-903-0845 | 28.0 ppb |
2019-12-10 | 9590-905-1135 | 43.0 ppb |
2019-12-10 | 9590-907-1455 | 29.0 ppb |