Thallium
CTWC - Unionville System
NOTE: CTWC - Unionville System purchases water from Metropolitan District Commission which is required to test for thallium. Sample information shown below was taken by Metropolitan District Commission.
Thalium is a naturally occurring metal released into the environment from metal smelting and coal burning. Exposure to too much thalium can cause hair loss, liver damage, reduced sperm motility and nervous system impairment.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2018 | ND | 1 | 0 | ND |
| 2019 | ND | 2 | 0 | ND |
| 2020 | ND | 2 | 0 | ND |
| 2021 | ND | 1 | 0 | ND |
| 2022 | ND | 1 | 0 | ND |
| 2023 | ND | 1 | 0 | ND |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
EWG Health Guideline: 0.1 ppb
The EWG Health Guideline of 0.1 ppb for thallium was defined 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. This health guideline protects against harm to internal organs.
EPA Maximum Contaminant
Level (MCL): 2 ppb
The legal limit for thallium, established in 1992, was based on analytical detection limits at the time that the standard was set.
ppb = parts per billion
All test results
NOTE: CTWC - Unionville System purchases water from Metropolitan District Commission which is required to test for thallium. Sample information shown below was taken by Metropolitan District Commission.
| Date | Lab ID | Result |
|---|---|---|
| 2018-07-18 | AE01630GE | ND |
| 2018-07-18 | AE01632GE | ND |
| 2018-07-18 | AE01631GE | ND |
| 2019-12-03 | CE70740 | ND |
| 2019-12-03 | CE70739 | ND |
| 2019-12-03 | CE70741 | ND |
| 2020-12-08 | IOC1 200600637 | ND |
| 2020-12-08 | IOC1 200600611 | ND |
| 2020-12-09 | IOC1 200600603 | ND |
| 2021-11-23 | E300107450 300107454 | ND |
| 2021-11-23 | E300107451 300107460 | ND |
| 2021-11-29 | E300109635 300109640 | ND |
| 2022-12-15 | E300287053 300287057 | ND |
| 2022-12-15 | E300287072 300287076 | ND |
| 2022-12-15 | E300287100 300287104 | ND |
| 2023-12-05 | E300456248 300456251 | ND |
| 2023-12-06 | E300456222 300456225 | ND |
| 2023-12-06 | E300456228 300456231 | ND |