Total trihalomethanes (TTHMs)
Old Bridge Village 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.
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 | 0.845 ppb | 8 | 8 | 0.320 ppb - 2.21 ppb |
| 2015 | 1.65 ppb | 8 | 7 | ND - 3.80 ppb |
| 2016 | 1.08 ppb | 8 | 8 | 0.250 ppb - 2.90 ppb |
| 2017 | 0.528 ppb | 8 | 4 | ND - 2.40 ppb |
| 2018 | 0.490 ppb | 8 | 3 | ND - 2.10 ppb |
| 2019 | 1.55 ppb | 8 | 5 | ND - 9.50 ppb |
ppb = parts per billion
State and national drinking water standards and health guidelines
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 | Result |
|---|---|
| 2014-03-19 | 0.410 ppb |
| 2014-03-19 | 0.600 ppb |
| 2014-06-23 | 0.950 ppb |
| 2014-06-23 | 1.000 ppb |
| 2014-09-24 | 0.870 ppb |
| 2014-09-24 | 0.320 ppb |
| 2014-12-17 | 0.400 ppb |
| 2014-12-17 | 2.21 ppb |
| 2015-03-24 | 0.720 ppb |
| 2015-03-24 | ND |
| 2015-06-28 | 0.480 ppb |
| 2015-06-28 | 1.50 ppb |
| 2015-09-16 | 2.60 ppb |
| 2015-09-16 | 0.800 ppb |
| 2015-12-15 | 3.80 ppb |
| 2015-12-15 | 3.30 ppb |
| 2016-03-31 | 0.250 ppb |
| 2016-03-31 | 0.250 ppb |
| 2016-06-23 | 0.380 ppb |
| 2016-06-23 | 1.40 ppb |
| 2016-09-25 | 2.90 ppb |
| 2016-09-25 | 0.670 ppb |
| 2016-12-11 | 1.30 ppb |
| 2016-12-11 | 1.50 ppb |
| 2017-03-27 | ND |
| 2017-03-27 | ND |
| 2017-06-28 | ND |
| 2017-06-28 | 0.420 ppb |
| 2017-09-30 | 0.740 ppb |
| 2017-09-30 | 2.40 ppb |
| 2017-12-15 | 0.660 ppb |
| 2017-12-15 | ND |
| 2018-03-17 | ND |
| 2018-03-17 | ND |
| 2018-06-20 | ND |
| 2018-06-20 | 2.10 ppb |
| 2018-09-24 | ND |
| 2018-09-24 | ND |
| 2018-12-31 | 0.820 ppb |
| 2018-12-31 | 1.000 ppb |
| 2019-03-31 | 0.320 ppb |
| 2019-03-31 | 0.320 ppb |
| 2019-06-24 | 1.60 ppb |
| 2019-06-24 | 9.50 ppb |
| 2019-09-23 | ND |
| 2019-09-23 | ND |
| 2019-12-18 | 0.640 ppb |
| 2019-12-18 | ND |