Mercury (inorganic)
Middletown Water Department
Mercury is a potent neurotoxin that also damages the kidneys and other internal organs. Mercury enters drinking water from industrial pollution, mining wastes and coal-fired power plants.
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 | 4 | 0 | ND |
| 2019 | ND | 3 | 0 | ND |
| 2020 | ND | 4 | 0 | ND |
| 2021 | ND | 4 | 0 | ND |
| 2022 | ND | 4 | 0 | ND |
| 2023 | ND | 4 | 0 | ND |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
EWG Health Guideline: 1.2 ppb
The EWG Health Guideline of 1.2 ppb for mercury (inorganic) 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 inorganic mercury, established in 1991, was based on toxicity studies conducted in laboratory animals in the 1970s and 1980s. This limit does not include any additional consideration of children’s health.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-03-01 | IOCR 200489002 | ND |
| 2018-03-01 | IOC1 200489001 | ND |
| 2018-04-16 | IOC1 200492152 | ND |
| 2018-04-16 | IOCR 200492151 | ND |
| 2019-05-13 | IOCR 200531894 | ND |
| 2019-05-21 | IOC1 200533082 | ND |
| 2019-05-21 | IOCR 200533084 | ND |
| 2020-05-06 | IOC1 200574724 | ND |
| 2020-05-06 | IOCR 200574725 | ND |
| 2020-05-14 | IOC1 200575834 | ND |
| 2020-05-14 | IOCR 200575835 | ND |
| 2021-03-30 | IOC1 200611335 | ND |
| 2021-03-30 | IOCR 200611337 | ND |
| 2021-03-30 | IOC1 200611336 | ND |
| 2021-04-07 | IOCR 200612106 | ND |
| 2022-05-11 | E300182524 300182535 | ND |
| 2022-05-11 | E300182526 300182548 | ND |
| 2022-05-11 | I300182528 300182554 | ND |
| 2022-05-11 | I300182529 300182559 | ND |
| 2023-06-23 | E300370712 300370717 | ND |
| 2023-06-23 | E300370718 300370723 | ND |
| 2023-06-23 | I300370724 300370730 | ND |
| 2023-06-23 | I300370731 300370737 | ND |