Chloroform
Meriden Water Division
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.
313
Samples
0
Samples exceeding legal limit (MCL)
270
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 | 23.6 ppb | 47 | 38 | ND - 79.0 ppb |
| 2015 | 21.5 ppb | 45 | 37 | ND - 74.0 ppb |
| 2016 | 35.2 ppb | 41 | 39 | ND - 74.0 ppb |
| 2017 | 41.6 ppb | 42 | 37 | ND - 98.0 ppb |
| 2018 | 28.9 ppb | 68 | 58 | ND - 65.0 ppb |
| 2019 | 22.3 ppb | 70 | 61 | ND - 47.0 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 |
|---|---|---|
| 2014-01-02 | BF94398VOC1 | 14.0 ppb |
| 2014-01-16 | BF99879VOC1 | 23.0 ppb |
| 2014-02-14 | BG09514TTHM | 33.0 ppb |
| 2014-02-14 | BG09515TTHM | 33.0 ppb |
| 2014-02-14 | BG09516TTHM | 45.0 ppb |
| 2014-02-14 | BG09517TTHM | 19.0 ppb |
| 2014-02-14 | BG09518TTHM | 18.0 ppb |
| 2014-02-14 | BG09519TTHM | 22.0 ppb |
| 2014-02-14 | BG09520TTHM | 45.0 ppb |
| 2014-02-14 | BG09521TTHM | 34.0 ppb |
| 2014-03-13 | BG18736VOC1 | ND |
| 2014-03-13 | BG18740VOC1 | ND |
| 2014-04-16 | BG33991VOC1 | ND |
| 2014-04-16 | BG33992VOC1 | ND |
| 2014-05-15 | BG45065TTHM | 27.0 ppb |
| 2014-05-15 | BG45066TTHM | 27.0 ppb |
| 2014-05-15 | BG45067TTHM | 64.0 ppb |
| 2014-05-15 | BG45068TTHM | 20.0 ppb |
| 2014-05-15 | BG45069TTHM | 25.0 ppb |
| 2014-05-15 | BG45070TTHM | 29.0 ppb |
| 2014-05-15 | BG45071TTHM | 24.0 ppb |
| 2014-05-15 | BG45072TTHM | 38.0 ppb |
| 2014-07-10 | BG72730VOC1 | 33.0 ppb |
| 2014-07-10 | BG72731VOC1 | 66.0 ppb |
| 2014-07-10 | BG72732VOC1 | 30.0 ppb |
| 2014-07-10 | BG72733VOC1 | 2.20 ppb |
| 2014-07-10 | BG72734VOC1 | ND |
| 2014-07-10 | BG72735VOC1 | ND |
| 2014-07-10 | BG72736VOC1 | ND |
| 2014-08-14 | BG94191TTHM | 9.30 ppb |
| 2014-08-14 | BG94192TTHM | 30.0 ppb |
| 2014-08-14 | BG94193TTHM | 79.0 ppb |
| 2014-08-14 | BG94194TTHM | 48.0 ppb |
| 2014-08-14 | BG94195TTHM | 28.0 ppb |
| 2014-08-14 | BG94196TTHM | 24.0 ppb |
| 2014-08-14 | BG94197TTHM | 46.0 ppb |
| 2014-08-14 | BG94198TTHM | 10.00 ppb |
| 2014-10-09 | BH25466VOC1 | ND |
| 2014-10-09 | BH25467VOC1 | ND |
| 2014-11-13 | BH40776TTHM | 15.0 ppb |
| 2014-11-13 | BH40777TTHM | 14.0 ppb |
| 2014-11-13 | BH40778TTHM | 45.0 ppb |
| 2014-11-13 | BH40779TTHM | 17.0 ppb |
| 2014-11-13 | BH40780TTHM | 18.0 ppb |
| 2014-11-13 | BH40781TTHM | 12.0 ppb |
| 2014-11-13 | BH40782TTHM | 27.0 ppb |
| 2014-11-13 | BH40783TTHM | 14.0 ppb |
| 2015-01-15 | BH63607VOC1 | ND |
| 2015-01-15 | BH63608VOC1 | ND |
| 2015-02-11 | BH73151TTHM | 4.80 ppb |
| 2015-02-11 | BH73146TTHM | 18.0 ppb |
| 2015-02-11 | BH73150TTHM | 17.0 ppb |
| 2015-02-11 | BH73149TTHM | 16.0 ppb |
| 2015-02-11 | BH73147TTHM | 15.0 ppb |
| 2015-02-11 | BH73153TTHM | 10.00 ppb |
| 2015-02-11 | BH73148TTHM | 31.0 ppb |
| 2015-02-13 | BH73314TTHM | 28.0 ppb |
| 2015-04-09 | BJ00527VOC1 | ND |
| 2015-05-13 | BJ16041TTHM | 15.0 ppb |
| 2015-05-13 | BJ16044TTHM | 36.0 ppb |
| 2015-05-13 | BJ16047TTHM | 43.0 ppb |
| 2015-05-13 | BJ16043TTHM | 57.0 ppb |
| 2015-05-13 | BJ16045TTHM | 25.0 ppb |
| 2015-05-13 | BJ16046TTHM | 12.0 ppb |
| 2015-05-13 | BJ16048TTHM | 10.00 ppb |
| 2015-05-13 | BJ16042TTHM | 22.0 ppb |
| 2015-06-18 | BJ33375VOC1 | 28.0 ppb |
| 2015-06-18 | BJ33376VOC1 | 74.0 ppb |
| 2015-06-18 | BJ33377VOC1 | 25.0 ppb |
| 2015-06-18 | BJ33378VOC1 | 2.20 ppb |
| 2015-06-18 | BJ33379VOC1 | ND |
| 2015-06-18 | BJ33380VOC1 | ND |
| 2015-06-18 | BJ33381VOC1 | ND |
| 2015-07-22 | BJ62367VOC1 | ND |
| 2015-08-13 | BJ74121TTHM | 41.0 ppb |
| 2015-08-13 | BJ74117TTHM | 25.0 ppb |
| 2015-08-13 | BJ74123TTHM | 39.0 ppb |
| 2015-08-13 | BJ74119TTHM | 54.0 ppb |
| 2015-08-13 | BJ74120TTHM | 42.0 ppb |
| 2015-08-13 | BJ74124TTHM | 15.0 ppb |
| 2015-08-13 | BJ74118TTHM | 31.0 ppb |
| 2015-08-13 | BJ74122TTHM | 25.0 ppb |
| 2015-10-22 | BK12423VOC1 | ND |
| 2015-11-12 | BK22058TTHM | 36.0 ppb |
| 2015-11-12 | BK22061TTHM | 25.0 ppb |
| 2015-11-12 | BK22059TTHM | 37.0 ppb |
| 2015-11-12 | BK22056TTHM | 16.0 ppb |
| 2015-11-12 | BK22055TTHM | 20.0 ppb |
| 2015-11-12 | BK22060TTHM | 18.0 ppb |
| 2015-11-12 | BK22057TTHM | 30.0 ppb |
| 2015-11-12 | BK22062TTHM | 14.0 ppb |
| 2015-11-19 | BK25835VOC1 | 9.40 ppb |
| 2016-02-11 | BK64212TTHM | 36.0 ppb |
| 2016-02-11 | BK64213TTHM | 36.0 ppb |
| 2016-02-11 | BK64214TTHM | 45.0 ppb |
| 2016-02-11 | BK64215TTHM | 28.0 ppb |
| 2016-02-11 | BK64216TTHM | 29.0 ppb |
| 2016-02-11 | BK64217TTHM | 55.0 ppb |
| 2016-02-11 | BK64218TTHM | 36.0 ppb |
| 2016-02-11 | BK64219TTHM | 29.0 ppb |
| 2016-03-03 | BK72987VOC1 | 10.00 ppb |
| 2016-04-14 | BN13851VOC1 | 15.0 ppb |
| 2016-05-12 | BN31089TTHM | 46.0 ppb |
| 2016-05-12 | BN31090TTHM | 47.0 ppb |
| 2016-05-12 | BN31091TTHM | 13.0 ppb |
| 2016-05-12 | BN31092TTHM | 42.0 ppb |
| 2016-05-12 | BN31093TTHM | 42.0 ppb |
| 2016-05-12 | BN31094TTHM | 3.70 ppb |
| 2016-05-12 | BN31095TTHM | 47.0 ppb |
| 2016-05-12 | BN31096TTHM | 32.0 ppb |
| 2016-06-30 | BN65088VOC1 | 32.0 ppb |
| 2016-06-30 | BN65089VOC1 | 67.0 ppb |
| 2016-06-30 | BN65090VOC1 | 24.0 ppb |
| 2016-06-30 | BN65091VOC1 | 3.30 ppb |
| 2016-06-30 | BN65092VOC1 | ND |
| 2016-06-30 | BN65093VOC1 | ND |
| 2016-07-14 | BN73019VOC1 | 17.0 ppb |
| 2016-08-11 | BN90757TTHM | 58.0 ppb |
| 2016-08-11 | BN90758TTHM | 59.0 ppb |
| 2016-08-11 | BN90759TTHM | 74.0 ppb |
| 2016-08-11 | BN90760TTHM | 60.0 ppb |
| 2016-08-11 | BN90761TTHM | 59.0 ppb |
| 2016-08-11 | BN90762TTHM | 43.0 ppb |
| 2016-08-11 | BN90763TTHM | 49.0 ppb |
| 2016-08-11 | BN90764TTHM | 50.0 ppb |
| 2016-11-16 | BV86932TTHM | 38.0 ppb |
| 2016-11-16 | BV86933TTHM | 39.0 ppb |
| 2016-11-16 | BV86934TTHM | 26.0 ppb |
| 2016-11-16 | BV86935TTHM | 34.0 ppb |
| 2016-11-16 | BV86936TTHM | 35.0 ppb |
| 2016-11-16 | BV86937TTHM | 13.0 ppb |
| 2016-11-16 | BV86938TTHM | 38.0 ppb |
| 2016-11-16 | BV86939TTHM | 32.0 ppb |
| 2017-02-16 | BX68635TTHM | 29.0 ppb |
| 2017-02-16 | BX68636TTHM | 29.0 ppb |
| 2017-02-16 | BX68637TTHM | 29.0 ppb |
| 2017-02-16 | BX68638TTHM | 24.0 ppb |
| 2017-02-16 | BX68639TTHM | 27.0 ppb |
| 2017-02-16 | BX68640TTHM | 18.0 ppb |
| 2017-02-16 | BX68641TTHM | 29.0 ppb |
| 2017-02-16 | BX68642TTHM | 22.0 ppb |
| 2017-04-06 | BY00212VOC1 | ND |
| 2017-05-11 | BY18976TTHM | 43.0 ppb |
| 2017-05-11 | BY18977TTHM | 45.0 ppb |
| 2017-05-11 | BY18978TTHM | 49.0 ppb |
| 2017-05-11 | BY18979TTHM | 38.0 ppb |
| 2017-05-11 | BY18980TTHM | 52.0 ppb |
| 2017-05-11 | BY18981TTHM | 12.0 ppb |
| 2017-05-11 | BY18982TTHM | 45.0 ppb |
| 2017-05-11 | BY18983TTHM | 47.0 ppb |
| 2017-06-15 | BY40610VOC1 | 37.0 ppb |
| 2017-06-15 | BY40611VOC1 | 20.0 ppb |
| 2017-06-15 | BY40612VOC1 | 24.0 ppb |
| 2017-06-15 | BY40613VOC1 | ND |
| 2017-06-22 | BY44703VOC1 | ND |
| 2017-06-29 | BY50178VOC1 | 58.0 ppb |
| 2017-07-20 | BY68706VOC1 | ND |
| 2017-08-10 | BY82544TTHM | 96.0 ppb |
| 2017-08-10 | BY82545TTHM | 96.0 ppb |
| 2017-08-10 | BY82546TTHM | 98.0 ppb |
| 2017-08-10 | BY82547TTHM | 53.0 ppb |
| 2017-08-10 | BY82548TTHM | 87.0 ppb |
| 2017-08-10 | BY82549TTHM | 87.0 ppb |
| 2017-08-10 | BY82550TTHM | 76.0 ppb |
| 2017-08-10 | BY82551TTHM | 81.0 ppb |
| 2017-08-17 | BY86088VOC1 | 2.90 ppb |
| 2017-10-05 | BZ15616VOC1 | ND |
| 2017-11-09 | BZ38914TTHM | 48.0 ppb |
| 2017-11-09 | BZ38915TTHM | 49.0 ppb |
| 2017-11-09 | BZ38916TTHM | 58.0 ppb |
| 2017-11-09 | BZ38917TTHM | 54.0 ppb |
| 2017-11-09 | BZ38918TTHM | 53.0 ppb |
| 2017-11-09 | BZ38919TTHM | 37.0 ppb |
| 2017-11-09 | BZ38920TTHM | 47.0 ppb |
| 2017-11-09 | BZ38921TTHM | 49.0 ppb |
| 2018-01-18 | BZ74951VOC1 | ND |
| 2018-02-08 | BZ86181TTHM | 36.0 ppb |
| 2018-02-08 | BZ86182TTHM | 37.0 ppb |
| 2018-02-08 | BZ86183TTHM | 24.0 ppb |
| 2018-02-08 | BZ86184TTHM | 35.0 ppb |
| 2018-02-08 | BZ86185TTHM | 40.0 ppb |
| 2018-02-08 | BZ86186TTHM | 6.60 ppb |
| 2018-02-08 | BZ86187TTHM | 35.0 ppb |
| 2018-02-08 | BZ86188TTHM | 39.0 ppb |
| 2018-03-12 | CA01226TTHM | 31.0 ppb |
| 2018-03-12 | CA01227TTHM | 28.0 ppb |
| 2018-03-12 | CA01228TTHM | 38.0 ppb |
| 2018-04-12 | CA19004TTHM | 32.0 ppb |
| 2018-04-12 | CA19005TTHM | 29.0 ppb |
| 2018-04-12 | CA19006TTHM | 39.0 ppb |
| 2018-05-10 | CA44958TTHM | 25.0 ppb |
| 2018-05-10 | CA44959TTHM | 25.0 ppb |
| 2018-05-10 | CA44960TTHM | 25.0 ppb |
| 2018-05-10 | CA44961TTHM | 43.0 ppb |
| 2018-05-10 | CA44962TTHM | 46.0 ppb |
| 2018-05-10 | CA44963TTHM | 10.00 ppb |
| 2018-05-10 | CA44964TTHM | 26.0 ppb |
| 2018-05-10 | CA44965TTHM | 31.0 ppb |
| 2018-05-17 | CA49083VOC1 | ND |
| 2018-06-07 | CA65949TTHM | 34.0 ppb |
| 2018-06-07 | CA65950TTHM | 33.0 ppb |
| 2018-06-07 | CA65951TTHM | 40.0 ppb |
| 2018-07-12 | CA88491TTHM | 39.0 ppb |
| 2018-07-12 | CA88492TTHM | 39.0 ppb |
| 2018-07-12 | CA88493TTHM | 43.0 ppb |
| 2018-07-19 | CA94410 | 37.0 ppb |
| 2018-07-19 | CA94411 | 43.0 ppb |
| 2018-07-19 | CA94412 | 10.00 ppb |
| 2018-07-19 | CA94413 | ND |
| 2018-07-26 | CA98719 | ND |
| 2018-08-09 | CB08267 | 49.0 ppb |
| 2018-08-09 | CB08268 | 48.0 ppb |
| 2018-08-09 | CB08269 | 44.0 ppb |
| 2018-08-09 | CB08270 | 53.0 ppb |
| 2018-08-09 | CB08271 | 55.0 ppb |
| 2018-08-09 | CB08272 | 65.0 ppb |
| 2018-08-09 | CB08273 | 47.0 ppb |
| 2018-08-09 | CB08274 | 50.0 ppb |
| 2018-08-09 | CB08263 | ND |
| 2018-08-23 | CB17441 | 37.0 ppb |
| 2018-09-13 | CB30717 | 41.0 ppb |
| 2018-09-13 | CB30718 | 39.0 ppb |
| 2018-09-13 | CB30719 | 44.0 ppb |
| 2018-09-20 | CB35508 | 3.50 ppb |
| 2018-09-20 | CB35511 | ND |
| 2018-09-27 | CB59877 | ND |
| 2018-10-11 | CB69876 | 27.0 ppb |
| 2018-10-11 | CB69877 | 27.0 ppb |
| 2018-10-11 | CB69878 | 30.0 ppb |
| 2018-10-11 | CB69872 | ND |
| 2018-11-14 | CB97384 | 20.0 ppb |
| 2018-11-14 | CB97385 | 20.0 ppb |
| 2018-11-14 | CB97386 | 47.0 ppb |
| 2018-11-14 | CB97387 | 22.0 ppb |
| 2018-11-14 | CB97371 | ND |
| 2018-11-20 | CC02615 | 25.0 ppb |
| 2018-11-20 | CC02616 | 57.0 ppb |
| 2018-11-20 | CC02617 | 22.0 ppb |
| 2018-11-20 | CC02618 | 26.0 ppb |
| 2018-12-07 | CC11054 | ND |
| 2018-12-12 | CC12839 | 22.0 ppb |
| 2018-12-12 | CC12840 | 21.0 ppb |
| 2018-12-12 | CC12841 | 23.0 ppb |
| 2019-01-09 | CC26159 | 20.0 ppb |
| 2019-01-09 | CC26160 | 22.0 ppb |
| 2019-01-09 | CC26161 | 22.0 ppb |
| 2019-02-06 | CC41805 | 2.40 ppb |
| 2019-02-13 | CC51440 | 14.0 ppb |
| 2019-02-13 | CC51441 | 15.0 ppb |
| 2019-02-13 | CC51442 | 15.0 ppb |
| 2019-02-13 | CC51443 | 19.0 ppb |
| 2019-02-13 | CC51444 | 18.0 ppb |
| 2019-02-13 | CC51445 | 5.90 ppb |
| 2019-02-13 | CC51446 | 18.0 ppb |
| 2019-02-13 | CC51447 | 18.0 ppb |
| 2019-03-13 | CC67336 | 15.0 ppb |
| 2019-03-13 | CC67337 | 17.0 ppb |
| 2019-03-13 | CC67338 | 21.0 ppb |
| 2019-04-10 | CC92173 | 17.0 ppb |
| 2019-04-10 | CC92174 | 17.0 ppb |
| 2019-04-10 | CC92175 | 33.0 ppb |
| 2019-04-25 | CD01551 | ND |
| 2019-05-08 | CD09263 | 22.0 ppb |
| 2019-05-08 | CD09264 | 22.0 ppb |
| 2019-05-08 | CD09265 | 21.0 ppb |
| 2019-05-08 | CD09266 | 31.0 ppb |
| 2019-05-08 | CD09267 | 35.0 ppb |
| 2019-05-08 | CD09268 | 21.0 ppb |
| 2019-05-08 | CD09269 | 23.0 ppb |
| 2019-05-08 | CD09270 | 22.0 ppb |
| 2019-05-08 | CD09272 | ND |
| 2019-06-12 | CD33213 | 27.0 ppb |
| 2019-06-12 | CD33214 | 27.0 ppb |
| 2019-06-12 | CD33215 | 36.0 ppb |
| 2019-06-19 | CD38010 | 0.640 ppb |
| 2019-06-19 | CD38011 | ND |
| 2019-06-19 | CD38012 | ND |
| 2019-06-26 | CD42474 | 33.0 ppb |
| 2019-06-26 | CD42475 | 24.0 ppb |
| 2019-06-26 | CD42476 | 7.10 ppb |
| 2019-07-10 | CD53538 | 35.0 ppb |
| 2019-07-10 | CD53539 | 36.0 ppb |
| 2019-07-10 | CD53540 | 45.0 ppb |
| 2019-07-10 | CD53533 | ND |
| 2019-08-07 | CD80098 | ND |
| 2019-08-14 | CD84984 | 39.0 ppb |
| 2019-08-14 | CD84985 | 42.0 ppb |
| 2019-08-14 | CD84986 | 22.0 ppb |
| 2019-08-14 | CD84987 | 41.0 ppb |
| 2019-08-14 | CD84988 | 41.0 ppb |
| 2019-08-14 | CD84989 | 25.0 ppb |
| 2019-08-14 | CD84990 | 36.0 ppb |
| 2019-08-14 | CD84991 | 24.0 ppb |
| 2019-09-04 | CD97370 | ND |
| 2019-09-11 | CE06528 | 34.0 ppb |
| 2019-09-11 | CE06529 | 34.0 ppb |
| 2019-09-11 | CE06530 | 45.0 ppb |
| 2019-10-02 | CE25548 | ND |
| 2019-10-09 | CE29947 | 39.0 ppb |
| 2019-10-09 | CE29948 | 39.0 ppb |
| 2019-10-09 | CE29949 | 47.0 ppb |
| 2019-11-06 | CE55216 | ND |
| 2019-11-14 | CE60570 | 27.0 ppb |
| 2019-11-14 | CE60571 | 23.0 ppb |
| 2019-11-14 | CE60572 | 32.0 ppb |
| 2019-11-14 | CE60573 | 29.0 ppb |
| 2019-11-14 | CE60574 | 30.0 ppb |
| 2019-11-14 | CE60575 | 14.0 ppb |
| 2019-11-14 | CE60576 | 47.0 ppb |
| 2019-11-14 | CE60577 | 19.0 ppb |
| 2019-12-11 | CE85082 | 17.0 ppb |
| 2019-12-11 | CE85083 | 18.0 ppb |
| 2019-12-11 | CE85084 | 22.0 ppb |