Know Your Environment. Protect Your Health.

Total trihalomethanes (TTHMs)

Hunters Creek Mobile Home Park

Trihalomethanes are cancer-causing contaminants that form during water treatment with chlorine and other disinfectants. The total trihalomethanes group includes four chemicals: chloroform, bromodichloromethane, dibromochloromethane and bromoform. Read More.

Studies conducted in the U.S. and Europe have found that drinking tap water that carries disinfection byproducts increases the risk of developing bladder cancer. In animal studies, all trihalomethanes cause liver, kidney and intestinal tumors. Some human epidemiological studies also reported an association between disinfection byproducts and an increased risk of problems during pregnancy, including spontaneous miscarriage, cardiovascular defects, neural tube defects and low birth weight.

The health guideline of 0.15 parts per billion, or ppb, for the group of four trihalomethanes, or THM4/TTHM, was defined in a peer-reviewed scientific study by EWG and represents a one-in-one-million lifetime cancer risk level.

Click here to read more about disinfection byproducts.

 

25

Samples

0

Samples exceeding legal limit (MCL)

15

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20186.39 ppb550.570 ppb - 11.0 ppb
20192.02 ppb53ND - 4.60 ppb
20200.300 ppb61ND - 1.80 ppb
20213.03 ppb331.60 ppb - 4.70 ppb
2022ND30ND
20233.47 ppb332.30 ppb - 4.40 ppb

ppb = parts per billion

State, National, and Health Guidelines for Drinking Water

EWG Health Guideline: 0.15 ppb

The health guideline of 0.15 parts per billion, or ppb, for the group of four trihalomethanes, or THM4/TTHM, was defined in a peer-reviewed scientific study by EWG and represents a one-in-one-million lifetime cancer risk level.

EPA Maximum Contaminant
Level (MCL): 80 ppb

The legal limit for the group of four trihalomethanes, established in 1998, was based on the need for residual disinfectant levels in water served to customers and the cost of treatment. This limit does not fully protect against the risk of cancer due to exposure to trihalomethanes.

ppb = parts per billion

All test results

Date Lab ID Result
2018-02-13480-131244-10.570 ppb
2018-08-1718H2138-036.30 ppb
2018-08-1718PH2138-0111.0 ppb
2018-08-1718H2138-028.70 ppb
2018-11-15480-145462-65.40 ppb
2019-02-1490225103.80 ppb
2019-08-143052462001ND
2019-08-1430524620021.70 ppb
2019-08-1430524620034.60 ppb
2019-12-313078958005ND
2020-03-173093628004ND
2020-05-193104459002 DBP1.80 ppb
2020-08-053120360 R2006995-3ND
2020-08-053120360 R2006995 -2ND
2020-08-053120360 R2006995 -1ND
2020-12-213148599001ND
2021-06-1631837630022.80 ppb
2021-06-1631837630011.60 ppb
2021-11-09R2111924-002 -14.70 ppb
2022-08-113258810001ND
2022-08-113258810002ND
2022-08-113258810003ND
2023-08-1633194560042.30 ppb
2023-08-1633194560053.70 ppb
2023-08-1633194560064.40 ppb