Hexachlorobenzene (HCB)
CTWC - Unionville System
Hexachlorobenzene is a cancer-causing, neurotoxic and hormone-disrupting chemical used as a pesticide until 1984. It is still found in landfills and hazardous waste sites, and can be detected in people.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2013 | N/A | 0 | 0 | N/A |
| 2014 | ND | 8 | 0 | ND |
| 2015 | ND | 4 | 0 | ND |
| 2016 | N/A | 0 | 0 | N/A |
| 2017 | ND | 4 | 0 | ND |
| 2018 | N/A | 0 | 0 | N/A |
| 2019 | ND | 12 | 0 | ND |
ppb = parts per billion
State and national drinking water standards and health guidelines
EWG Health Guideline 0.03 ppb
The EWG Health Guideline of 0.03 ppb for hexachlorobenzene 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 cancer.
EPA Maximum Contaminant
Level (MCL) 1 ppb
The legal limit for hexachlorobenzene, established in 1992, was based on analytical detection limits at the time that the standard was set. This limit may not fully protect against the risk of cancer due to hexachlorobenzene exposure.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2014-01-21 | BG01716SOC5 | ND |
| 2014-01-21 | BG01717SOC5 | ND |
| 2014-01-21 | BG01713SOC5 | ND |
| 2014-01-22 | BG01714SOC5 | ND |
| 2014-01-22 | BG01715SOC5 | ND |
| 2014-01-22 | BG01718SOC5 | ND |
| 2014-01-22 | BG01719SOC5 | ND |
| 2014-02-14 | BG09385SOC5 | ND |
| 2015-03-03 | 3199324 | ND |
| 2015-06-03 | 3254573 | ND |
| 2015-07-13 | BJ46102SOC5 | ND |
| 2015-07-15 | BJ46999SOC5 | ND |
| 2017-08-29 | BY91937SOC5 | ND |
| 2017-08-29 | BY91939SOC5 | ND |
| 2017-08-29 | BY91938SOC5 | ND |
| 2017-11-21 | BZ45452SOC5 | ND |
| 2019-09-17 | SOC 200549386 | ND |
| 2019-09-17 | SOC 200549392 | ND |
| 2019-09-25 | SOC 200550426 | ND |
| 2019-09-25 | SOC 200550428 | ND |
| 2019-09-25 | SOC 200550427 | ND |
| 2019-10-02 | SOC 200551433 | ND |
| 2019-10-02 | SOC 200551434 | ND |
| 2019-10-09 | SOC 200552469 | ND |
| 2019-10-10 | SOC 200552468 | ND |
| 2019-10-10 | SOC 200552467 | ND |
| 2019-10-10 | SOC 200552466 | ND |
| 2019-10-10 | SOC 200552465 | ND |