Trichloroacetic acid
Greendale Waterworks
Trichloroacetic acid, one of the group of five haloacetic acids regulated by federal standards, is formed when chlorine or other disinfectants are used to treat drinking water. Haloacetic acids and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2014 | 0.872 ppb | 16 | 12 | ND - 2.00 ppb |
| 2015 | 0.897 ppb | 16 | 15 | ND - 1.30 ppb |
| 2016 | 0.569 ppb | 16 | 15 | ND - 0.980 ppb |
| 2017 | 0.769 ppb | 16 | 16 | 0.350 ppb - 0.940 ppb |
| 2018 | 0.883 ppb | 16 | 16 | 0.440 ppb - 1.40 ppb |
| 2019 | 0.381 ppb | 16 | 13 | ND - 0.780 ppb |
ppb = parts per billion
State and national drinking water standards and health guidelines
EWG Health Guideline 0.1 ppb
The EWG Health Guideline of 0.1 ppb for trichloroacetic acid was proposed in 2020 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.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 |
|---|---|---|
| 2014-03-05 | 773320 | 0.590 ppb |
| 2014-03-05 | 773319 | 0.660 ppb |
| 2014-03-05 | 773318 | 0.700 ppb |
| 2014-03-05 | 773321 | 0.500 ppb |
| 2014-06-03 | 794165 | 1.70 ppb |
| 2014-06-03 | 794166 | 1.70 ppb |
| 2014-06-03 | 794167 | 1.90 ppb |
| 2014-06-03 | 794168 | 2.00 ppb |
| 2014-09-02 | 814784 | ND |
| 2014-09-02 | 814782 | ND |
| 2014-09-02 | 814781 | ND |
| 2014-09-02 | 814783 | ND |
| 2014-12-02 | 833632 | 1.10 ppb |
| 2014-12-02 | 833633 | 1.30 ppb |
| 2014-12-02 | 833634 | 1.10 ppb |
| 2014-12-02 | 833635 | 0.700 ppb |
| 2015-03-04 | 846448 | 0.930 ppb |
| 2015-03-04 | 846447 | 0.940 ppb |
| 2015-03-04 | 846445 | 1.000 ppb |
| 2015-03-04 | 846446 | 1.20 ppb |
| 2015-06-02 | 863110 | 0.680 ppb |
| 2015-06-02 | 863112 | 0.700 ppb |
| 2015-06-02 | 863111 | 0.960 ppb |
| 2015-06-02 | 863113 | 1.000 ppb |
| 2015-09-02 | 880649 | 0.590 ppb |
| 2015-09-02 | 880646 | 1.10 ppb |
| 2015-09-02 | 880647 | 0.900 ppb |
| 2015-09-02 | 880648 | 0.750 ppb |
| 2015-12-02 | 896273 | ND |
| 2015-12-02 | 896272 | 1.30 ppb |
| 2015-12-02 | 896270 | 1.10 ppb |
| 2015-12-02 | 896271 | 1.20 ppb |
| 2016-03-09 | 909382 | ND |
| 2016-03-09 | 909381 | 0.460 ppb |
| 2016-03-09 | 909380 | 0.470 ppb |
| 2016-03-09 | 909379 | 0.520 ppb |
| 2016-06-08 | 925875 | 0.980 ppb |
| 2016-06-08 | 925872 | 0.960 ppb |
| 2016-06-08 | 925873 | 0.930 ppb |
| 2016-06-08 | 925874 | 0.900 ppb |
| 2016-09-07 | 944006 | 0.220 ppb |
| 2016-09-07 | 944008 | 0.220 ppb |
| 2016-09-07 | 944007 | 0.230 ppb |
| 2016-09-07 | 944009 | 0.280 ppb |
| 2016-11-30 | 962267 | 0.670 ppb |
| 2016-11-30 | 962266 | 0.710 ppb |
| 2016-11-30 | 962265 | 0.770 ppb |
| 2016-11-30 | 962264 | 0.780 ppb |
| 2017-03-08 | 976956 | 0.650 ppb |
| 2017-03-08 | 976957 | 0.350 ppb |
| 2017-03-08 | 976958 | 0.450 ppb |
| 2017-03-08 | 976955 | 0.620 ppb |
| 2017-06-07 | 996318 | 0.870 ppb |
| 2017-06-07 | 996320 | 0.880 ppb |
| 2017-06-07 | 996319 | 0.880 ppb |
| 2017-06-07 | 996321 | 0.900 ppb |
| 2017-09-06 | 1016385 | 0.940 ppb |
| 2017-09-06 | 1016384 | 0.940 ppb |
| 2017-09-06 | 1016382 | 0.920 ppb |
| 2017-09-06 | 1016383 | 0.700 ppb |
| 2017-12-06 | 1032495 | 0.850 ppb |
| 2017-12-06 | 1032494 | 0.790 ppb |
| 2017-12-06 | 1032492 | 0.740 ppb |
| 2017-12-06 | 1032493 | 0.820 ppb |
| 2018-03-07 | 1044157 | 1.20 ppb |
| 2018-03-07 | 1044156 | 1.40 ppb |
| 2018-03-07 | 1044159 | 1.20 ppb |
| 2018-03-07 | 1044158 | 1.20 ppb |
| 2018-06-06 | 1059687 | 1.10 ppb |
| 2018-06-06 | 1059685 | 1.10 ppb |
| 2018-06-06 | 1059686 | 1.000 ppb |
| 2018-06-06 | 1059684 | 0.990 ppb |
| 2018-09-05 | 1078437 | 0.780 ppb |
| 2018-09-05 | 1078434 | 0.750 ppb |
| 2018-09-05 | 1078436 | 0.680 ppb |
| 2018-09-05 | 1078435 | 0.660 ppb |
| 2018-12-06 | 1096507 | 0.450 ppb |
| 2018-12-06 | 1096509 | 0.530 ppb |
| 2018-12-06 | 1096510 | 0.440 ppb |
| 2018-12-06 | 1096508 | 0.650 ppb |
| 2019-03-06 | 1108244 | 0.640 ppb |
| 2019-03-06 | 1108245 | 0.730 ppb |
| 2019-03-06 | 1108243 | 0.760 ppb |
| 2019-03-06 | 1108246 | 0.780 ppb |
| 2019-06-05 | 1125654 | 0.370 ppb |
| 2019-06-05 | 1125652 | 0.380 ppb |
| 2019-06-05 | 1125653 | 0.360 ppb |
| 2019-06-05 | 1125651 | 0.360 ppb |
| 2019-09-04 | 1145423 | 0.330 ppb |
| 2019-09-04 | 1145425 | 0.340 ppb |
| 2019-09-04 | 1145424 | 0.340 ppb |
| 2019-09-04 | 1145422 | 0.360 ppb |
| 2019-12-04 | 1163572 | ND |
| 2019-12-04 | 1163571 | ND |
| 2019-12-04 | 1163573 | ND |
| 2019-12-04 | 1163570 | 0.350 ppb |