Know Your Environment. Protect Your Health.

Cyanide

Gonzales County Water Supply Corporation

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.

 

14

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2018ND10ND
2019ND10ND
20208.33 ppb61ND - 50.0 ppb
202160.0 ppb1160.0 ppb
202280.0 ppb2230.0 ppb - 130.0 ppb
2023ND60ND

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

Date Lab ID Result
2018-12-12AE48591ND
2019-03-05AE57078ND
2020-01-21AE94233ND
2020-01-21AE9423450.0 ppb
2020-01-21AE94236ND
2020-03-10AF01912ND
2020-03-10AF01913ND
2020-03-10AF01914ND
2023-03-15AG33154ND
2023-03-15AG33155ND
2023-03-29AG34737ND
2023-06-21AG45161ND
2023-06-21AG45163ND
2023-06-21AG45164ND