Dichloroacetic acid

San Lorenzo Valley Water District

Dichloroacetic 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.

MORE ABOUT THIS CONTAMINANT

121

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	2.17 ppb	20	11	ND - 7.60 ppb
2015	4.76 ppb	20	13	ND - 18.0 ppb
2016	7.75 ppb	20	18	ND - 17.0 ppb
2017	6.18 ppb	20	17	ND - 16.0 ppb
2018	5.00 ppb	21	17	ND - 13.0 ppb
2019	9.34 ppb	20	18	ND - 22.0 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.2 ppb

The EWG Health Guideline of 0.2 ppb for dichloroacetic 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
2014-01-17	5810-805-0830	7.10 ppb
2014-02-12	9590-801-0900	4.50 ppb
2014-02-12	9590-802-0915	4.40 ppb
2014-02-12	9590-803-1445	ND
2014-02-12	9590-804-0945	3.20 ppb
2014-04-30	5810-805-1238	ND
2014-05-20	9590-801-0950	1.90 ppb
2014-05-20	9590-802-1015	7.60 ppb
2014-05-20	9590-803-1110	ND
2014-05-20	9590-804-1035	2.70 ppb
2014-07-30	5810-805-1012	ND
2014-08-13	9590-801-1000	ND
2014-08-13	9590-802-1020	2.40 ppb
2014-08-13	9590-803-1400	ND
2014-08-13	9590-804-0900	1.50 ppb
2014-10-29	5810-805-1049	ND
2014-11-12	9590-801-1200	ND
2014-11-12	9590-802-1230	4.20 ppb
2014-11-12	9590-803-1430	ND
2014-11-12	9590-804-1245	3.90 ppb
2015-01-27	5810-805-1145	ND
2015-02-11	9590-801-1520	18.0 ppb
2015-02-11	9590-802-1455	14.0 ppb
2015-02-11	9590-803-1430	13.0 ppb
2015-02-11	9590-804-1420	5.60 ppb
2015-04-27	5810-805-0750	ND
2015-05-20	9590-801-1550	9.60 ppb
2015-05-20	9590-802-1530	10.00 ppb
2015-05-20	9590-803-1450	ND
2015-05-20	9590-804-1500	8.60 ppb
2015-07-07	5810-805-1213	ND
2015-08-12	9590-801-1345	1.10 ppb
2015-08-12	9590-802-1315	3.70 ppb
2015-08-12	9590-803-1100	ND
2015-08-12	9590-804-1200	4.20 ppb
2015-10-14	5810-805-1115	ND
2015-11-17	9590-801-1100	1.30 ppb
2015-11-17	9590-802-1130	2.60 ppb
2015-11-17	9590-803-1430	ND
2015-11-17	9590-804-1200	3.50 ppb
2016-01-14	5810-805-1023	2.40 ppb
2016-02-10	9590-801-1500	15.0 ppb
2016-02-10	9590-802-1440	13.0 ppb
2016-02-10	9590-803-1400	11.0 ppb
2016-02-10	9590-804-1530	17.0 ppb
2016-04-21	5810-805-0939	10.00 ppb
2016-05-11	9590-801-1300	4.80 ppb
2016-05-11	9590-802-1230	8.10 ppb
2016-05-11	9590-803-1130	2.90 ppb
2016-05-11	9590-804-1200	2.50 ppb
2016-08-11	9590-801-1050	3.90 ppb
2016-08-11	9590-802-1030	5.60 ppb
2016-08-11	9590-803-1150	ND
2016-08-11	9590-804-1125	8.80 ppb
2016-08-25	9590-805-1220	ND
2016-11-03	9590-805-1150	2.00 ppb
2016-11-05	9590-801-1130	15.0 ppb
2016-11-05	9590-802-1100	14.0 ppb
2016-11-05	9590-803-1245	9.30 ppb
2016-11-05	9590-804-1130	9.60 ppb
2017-02-15	9590-801-0945	16.0 ppb
2017-02-15	9590-802-1100	10.00 ppb
2017-02-15	9590-803-1050	1.90 ppb
2017-02-15	9590-804-1140	14.0 ppb
2017-03-08	9590-805-1220	5.50 ppb
2017-05-11	9590-801-1315	3.30 ppb
2017-05-11	9590-802-1245	9.10 ppb
2017-05-11	9590-804-1230	9.90 ppb
2017-05-11	9590-805-1130	9.00 ppb
2017-05-31	9590-803-1030	ND
2017-08-17	9590-801-0945	8.20 ppb
2017-08-17	9590-802-1045	8.30 ppb
2017-08-17	9590-803-1130	ND
2017-08-17	9590-804-1015	9.20 ppb
2017-08-17	9590-805-1010	1.000 ppb
2017-11-07	9590-801-1200	1.30 ppb
2017-11-07	9590-802-1130	7.70 ppb
2017-11-07	9590-803-1040	ND
2017-11-07	9590-804-1110	8.00 ppb
2017-11-07	9590-805-0945	1.10 ppb
2018-02-15	9590-801-0930	3.10 ppb
2018-02-15	9590-802-1030	13.0 ppb
2018-02-15	9590-803-1230	ND
2018-02-15	9590-804-1000	13.0 ppb
2018-02-15	9590-805-0920	1.80 ppb
2018-05-17	9590-801-1030	11.0 ppb
2018-05-17	9590-802-1000	8.50 ppb
2018-05-17	9590-803-0900	7.40 ppb
2018-05-17	9590-804-0930	7.50 ppb
2018-05-17	9590-805-1030	5.10 ppb
2018-08-15	9590-801-0915	7.10 ppb
2018-08-15	9590-802-0900	4.00 ppb
2018-08-15	9590-802-1115	ND
2018-08-15	9590-803-1030	ND
2018-08-15	9590-804-0945	8.50 ppb
2018-08-15	9590-805-1045	1.50 ppb
2018-11-15	9590-801-1030	1.40 ppb
2018-11-15	9590-802-1100	4.80 ppb
2018-11-15	9590-803-1230	ND
2018-11-15	9590-804-1000	4.90 ppb
2018-11-15	9590-805-1300	2.30 ppb
2019-02-21	9590-801-0940	10.00 ppb
2019-02-21	9590-802-0905	20.0 ppb
2019-02-21	9590-803-0940	15.0 ppb
2019-02-21	9590-804-0830	22.0 ppb
2019-02-21	9590-805-0900	17.0 ppb
2019-05-15	9590-801-1045	9.80 ppb
2019-05-15	9590-802-1105	12.0 ppb
2019-05-15	9590-803-1335	9.10 ppb
2019-05-15	9590-804-1215	8.30 ppb
2019-05-15	9590-805-1310	11.0 ppb
2019-08-14	9590-801-1200	11.0 ppb
2019-08-14	9590-802-1130	8.80 ppb
2019-08-14	9590-803-1445	1.20 ppb
2019-08-14	9590-804-1100	9.10 ppb
2019-08-14	9590-805-1400	ND
2019-11-19	9590-801-1040	6.30 ppb
2019-11-19	9590-802-1015	7.00 ppb
2019-11-19	9590-803-0830	ND
2019-11-19	9590-804-0945	7.20 ppb
2019-11-19	9590-805-0910	2.00 ppb