Cyanide
CTWC - Unionville System
NOTE: CTWC - Unionville System purchases water from Metropolitan District Commission which is required to test for cyanide. Sample information shown below was taken by Metropolitan District Commission.
Cyanide is a toxic chemical that causes central nervous system and thyroid toxicity. Water contamination is generally the result of metal mining and chemical industry waste, runoff from agriculture and road salts used for melting ice.
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: 150 ppb
The EWG Health Guideline of 150 ppb for cyanide 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 the brain and nervous system.
EPA Maximum Contaminant
Level (MCL): 200 ppb
The legal limit for cyanide, established in 1992, was based on a 1955 toxicity study conducted in laboratory animals. This limit does not include any additional consideration of children’s health.
ppb = parts per billion
All test results
NOTE: CTWC - Unionville System purchases water from Metropolitan District Commission which is required to test for cyanide. Sample information shown below was taken by Metropolitan District Commission.
| Date | Lab ID | Result |
|---|---|---|
| 2018-07-18 | CA93877 | ND |
| 2018-07-18 | CA93878 | ND |
| 2018-07-18 | CA93875 | ND |
| 2018-07-18 | CA93874 | ND |
| 2018-07-18 | CA93873 | ND |
| 2018-07-18 | CA93870 | ND |
| 2018-07-18 | CA93876 | ND |
| 2019-10-09 | CE39276 | ND |
| 2019-10-09 | CE39273 | ND |
| 2019-10-09 | CE39274 | ND |
| 2019-10-09 | CE39275 | ND |
| 2019-10-09 | CE39269 | ND |
| 2019-10-09 | CE39270 | ND |
| 2019-10-09 | CE39268 | ND |
| 2020-12-08 | IOC1 200600637 | ND |
| 2020-12-08 | IOC1 200600611 | ND |
| 2020-12-08 | IOCR 200600614 | ND |
| 2020-12-08 | IOCR 200600615 | ND |
| 2020-12-08 | IOCR 200600616 | ND |
| 2020-12-08 | IOCR 200600617 | ND |
| 2020-12-09 | IOC1 200600603 | ND |
| 2021-11-23 | E300107450 300107455 | ND |
| 2021-11-23 | I300107476 300107481 | ND |
| 2021-11-23 | E300107451 300107461 | ND |
| 2021-11-29 | E300109635 300109641 | ND |
| 2021-11-29 | I300109610 300109615 | ND |
| 2021-11-30 | I300109649 300109655 | ND |
| 2021-11-30 | I300109650 300109661 | ND |
| 2022-12-08 | I300283837 300283844 | ND |
| 2022-12-08 | 300283822 300283829B | ND |
| 2022-12-15 | E300287100 300287105 | ND |
| 2022-12-15 | I300287081 300287088 | ND |
| 2022-12-15 | I300287109 300287114 | ND |
| 2022-12-15 | E300287072 300287077 | ND |
| 2022-12-15 | E300287053 300287058 | ND |
| 2023-12-05 | E300456248 300456252 | ND |
| 2023-12-05 | I300456268 300456273 | ND |
| 2023-12-05 | I300456261 300456266 | ND |
| 2023-12-05 | I300456281 300456286 | ND |
| 2023-12-06 | E300456222 300456226 | ND |
| 2023-12-06 | E300456228 300456232 | ND |
| 2023-12-06 | I300456234 300456239 | ND |