Chloroform

Pawtucket

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

200

Samples

Samples exceeding legal limit (MCL)

158

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Detections	Range of results
2013	N/A	0	0	N/A
2014	15.0 ppb	16	8	ND - 36.0 ppb
2015	14.6 ppb	36	24	ND - 37.0 ppb
2016	28.3 ppb	36	32	ND - 60.0 ppb
2017	26.2 ppb	46	36	ND - 82.0 ppb
2018	20.4 ppb	46	42	ND - 47.0 ppb
2019	12.7 ppb	20	16	ND - 26.0 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
2014-01-27	1401232-01_TO12	ND
2014-03-27	1402016-01_TO12	ND
2014-03-27	1402016-02_TO12	ND
2014-04-07	1402198-07_TO12	ND
2014-04-07	1402198-03_TO12	ND
2014-04-07	1402198-04_TO12	ND
2014-04-07	1402198-05_TO12	ND
2014-04-07	1402198-06_TO12	ND
2014-07-09	1407-15125-001	34.0 ppb
2014-07-09	1407-15125-002	36.0 ppb
2014-07-09	1407-15125-003	28.0 ppb
2014-07-09	1407-15125-004	30.0 ppb
2014-07-09	1407-15125-005	31.0 ppb
2014-07-09	1407-15125-006	31.0 ppb
2014-07-09	1407-15125-007	19.0 ppb
2014-07-09	1407-15125-008	31.0 ppb
2015-01-14	1501-01032-001	ND
2015-01-14	1501-01032-002	ND
2015-01-14	1501-01032-003	ND
2015-01-14	1501-01032-004	ND
2015-01-14	1501-01032-005TH	ND
2015-01-14	1501-01032-007TH	ND
2015-01-14	1501-01032-008TH	ND
2015-01-14	1501-10132-006TH	ND
2015-03-31	1501722-03_TO12	ND
2015-03-31	1501722-02_TO12	ND
2015-03-31	1501722-01_TO12	ND
2015-04-08	1504-07021-001T	17.0 ppb
2015-04-08	1504-07021-002T	14.0 ppb
2015-04-08	1504-07021-003T	16.0 ppb
2015-04-08	1504-07021-004T	22.0 ppb
2015-04-08	1504-07021-005T	20.0 ppb
2015-04-08	1504-07021-006T	20.0 ppb
2015-04-08	1504-07021-007T	15.0 ppb
2015-04-08	1504-07021-008T	16.0 ppb
2015-04-28	1501999-02_TO12	ND
2015-07-08	1507-14382-001	33.0 ppb
2015-07-08	1507-14382-002	18.0 ppb
2015-07-08	1507-14382-003	22.0 ppb
2015-07-08	1507-14382-004	28.0 ppb
2015-07-08	1507-14382-005	32.0 ppb
2015-07-08	1507-14382-006	26.0 ppb
2015-07-08	1507-14382-007	19.0 ppb
2015-07-08	1507-14382-008	37.0 ppb
2015-10-07	1510-21765-001	33.0 ppb
2015-10-07	1510-21765-002	14.0 ppb
2015-10-07	1510-21765-003	17.0 ppb
2015-10-07	1510-21765-004	25.0 ppb
2015-10-07	1510-21765-005	22.0 ppb
2015-10-07	1510-21765-006	20.0 ppb
2015-10-07	1510-21765-007	21.0 ppb
2015-10-07	1510-21765-008	17.0 ppb
2016-01-06	1601-00470-001TH	44.0 ppb
2016-01-06	1601-00470-002TH	24.0 ppb
2016-01-06	1601-00470-003TH	26.0 ppb
2016-01-06	1601-00470-004TH	48.0 ppb
2016-01-06	1601-00470-005TH	35.0 ppb
2016-01-06	1601-00470-006TH	30.0 ppb
2016-01-06	1601-00470-007TH	36.0 ppb
2016-01-06	1601-00470-008TH	26.0 ppb
2016-03-22	1601566-01_TO12	ND
2016-03-22	1601566-02_TO12	ND
2016-04-06	1604-07876-001TH	29.0 ppb
2016-04-06	1604-07876-002TH	18.0 ppb
2016-04-06	1604-07876-003TH	21.0 ppb
2016-04-06	1604-07876-004TH	46.0 ppb
2016-04-06	1604-07876-005TH	26.0 ppb
2016-04-06	1604-07876-006TH	26.0 ppb
2016-04-06	1604-07876-007TH	25.0 ppb
2016-04-06	1604-07876-008TH	24.0 ppb
2016-06-07	1602458-01_TO12	ND
2016-06-27	1602860-01_TO12	ND
2016-07-06	1607-15553-001T	60.0 ppb
2016-07-06	1607-15553-002T	31.0 ppb
2016-07-06	1607-15553-003T	31.0 ppb
2016-07-06	1607-15553-004T	37.0 ppb
2016-07-06	1607-15553-005T	47.0 ppb
2016-07-06	1607-15553-006T	30.0 ppb
2016-07-06	1607-15553-007T	22.0 ppb
2016-07-06	1607-15553-008T	30.0 ppb
2016-10-05	1610-23719-004	54.0 ppb
2016-10-05	1610-23719-005	23.0 ppb
2016-10-05	1610-23719-006	25.0 ppb
2016-10-05	1610-23719-007	36.0 ppb
2016-10-05	1610-23719-008	34.0 ppb
2016-10-05	1610-23719-009	31.0 ppb
2016-10-05	1610-23719-010	18.0 ppb
2016-10-05	1610-23719-011	24.0 ppb
2017-01-04	1701-00325-001	24.0 ppb
2017-01-04	1701-00325-002	17.0 ppb
2017-01-04	1701-00325-003	17.0 ppb
2017-01-04	1701-00325-004	27.0 ppb
2017-01-04	1701-00325-005	24.0 ppb
2017-01-04	1701-00325-006	19.0 ppb
2017-01-04	1701-00325-007	13.0 ppb
2017-01-04	1701-00325-008	17.0 ppb
2017-02-01	1701096-01_TO12	ND
2017-03-29	1701674-02_TO12	ND
2017-03-29	1701674-01_TO12	ND
2017-04-05	1704-07152-005	32.0 ppb
2017-04-05	1704-07152-006	27.0 ppb
2017-04-05	1704-07152-008	45.0 ppb
2017-04-05	1704-07152-009	38.0 ppb
2017-04-05	1704-07152-010	37.0 ppb
2017-04-05	1704-07152-011	25.0 ppb
2017-04-05	1704-07152-012	30.0 ppb
2017-04-06	1704-07152-007	30.0 ppb
2017-04-17	1701862-06_TO12	ND
2017-04-17	1701862-02_TO12	ND
2017-04-17	1701862-01_TO12	ND
2017-04-17	1701862-03_TO12	ND
2017-04-17	1701862-04_TO12	ND
2017-07-05	1707-14358-002	38.0 ppb
2017-07-05	1707-14358-003	29.0 ppb
2017-07-05	1707-14358-004	31.0 ppb
2017-07-05	1707-14358-005	42.0 ppb
2017-07-05	1707-14358-006	53.0 ppb
2017-07-05	1707-14358-007	34.0 ppb
2017-07-05	1707-14358-008	22.0 ppb
2017-07-05	1707-14358-009	39.0 ppb
2017-10-04	1710-21672-001	82.0 ppb
2017-10-04	1710-21672-002	35.0 ppb
2017-10-04	1710-21672-003	44.0 ppb
2017-10-04	1710-21672-004	62.0 ppb
2017-10-04	1710-21672-005	63.0 ppb
2017-10-04	1710-21672-006	47.0 ppb
2017-10-04	1710-21672-007	30.0 ppb
2017-10-04	1710-21672-008	42.0 ppb
2017-11-01	1704846-01_TO12	ND
2017-12-20	1712-27631-001	7.80 ppb
2017-12-20	1712-27631-002	ND
2017-12-20	1712-27631-003	19.0 ppb
2017-12-20	1712-27631-004	31.0 ppb
2017-12-20	1712-27631-005	32.0 ppb
2018-01-03	1801-00177-004	29.0 ppb
2018-01-03	1801-00177-005	15.0 ppb
2018-01-03	1801-00177-006	21.0 ppb
2018-01-03	1801-00177-007	30.0 ppb
2018-01-03	1801-00177-008	26.0 ppb
2018-01-03	1801-00177-009	22.0 ppb
2018-01-03	1801-00177-010	15.0 ppb
2018-01-03	1801-00177-011	17.0 ppb
2018-01-24	1801-01833-001	4.50 ppb
2018-01-24	1801-01833-002	2.70 ppb
2018-01-24	1801-01833-003	5.30 ppb
2018-01-24	1801-01833-004	22.0 ppb
2018-01-24	1801-01833-005	20.0 ppb
2018-02-28	1803-04382-001	5.40 ppb
2018-02-28	1803-04382-002	3.50 ppb
2018-02-28	1803-04382-003	15.0 ppb
2018-02-28	1803-04382-004	19.0 ppb
2018-02-28	1803-04382-005	20.0 ppb
2018-03-28	1801540-01_TO12	ND
2018-03-28	1801540-02_TO12	ND
2018-03-28	1801540-03_TO12	ND
2018-04-04	1804-06826-001	23.0 ppb
2018-04-04	1804-06826-002	14.0 ppb
2018-04-04	1804-06826-003	17.0 ppb
2018-04-04	1804-06826-004	25.0 ppb
2018-04-04	1804-06826-005	18.0 ppb
2018-04-04	1804-06826-006	17.0 ppb
2018-04-04	1804-06826-007	13.0 ppb
2018-04-04	1804-06826-008	15.0 ppb
2018-04-30	1801885-02_TO12	ND
2018-07-05	1807-14124-001	35.0 ppb
2018-07-05	1807-14124-002	22.0 ppb
2018-07-05	1807-14124-003	26.0 ppb
2018-07-05	1807-14124-004	29.0 ppb
2018-07-05	1807-14124-005	34.0 ppb
2018-07-05	1807-14124-006	24.0 ppb
2018-07-05	1807-14124-007	18.0 ppb
2018-07-05	1807-14124-008	38.0 ppb
2018-10-03	1810-21399-001	47.0 ppb
2018-10-03	1810-21399-002	22.0 ppb
2018-10-03	1810-21399-003	31.0 ppb
2018-10-03	1810-21399-004	44.0 ppb
2018-10-03	1810-21399-005	45.0 ppb
2018-10-03	1810-21399-006	38.0 ppb
2018-10-03	1810-21399-007	21.0 ppb
2018-10-03	1810-21399-008	32.0 ppb
2019-01-02	1901-00209-001	26.0 ppb
2019-01-02	1901-00209-002	13.0 ppb
2019-01-02	1901-00209-003	18.0 ppb
2019-01-02	1901-00209-004	22.0 ppb
2019-01-02	1901-00209-005	22.0 ppb
2019-01-02	1901-00209-006	20.0 ppb
2019-01-02	1901-00209-007	21.0 ppb
2019-01-02	1901-00209-008	15.0 ppb
2019-03-26	1901463-02_TO12	ND
2019-03-26	1901463-03_TO12	ND
2019-03-26	1901463-01_TO12	ND
2019-04-03	1904-06057-001	15.0 ppb
2019-04-03	1904-06057-002	8.80 ppb
2019-04-03	1904-06057-003	11.0 ppb
2019-04-03	1904-06057-004	15.0 ppb
2019-04-03	1904-06057-005	15.0 ppb
2019-04-03	1904-06057-006	12.0 ppb
2019-04-03	1904-06057-007	9.70 ppb
2019-04-03	1904-06057-008	9.70 ppb
2019-06-27	1902770-01_TO12	ND