Know Your Environment. Protect Your Health.

Perchlorate

South Grafton Water District

Perchlorate, a component of rocket fuel, occurs both naturally and as a synthetic chemical. Ingested perchlorate interferes with thyroid function. Exposure to perchlorate during pregnancy and childhood can impair cognitive development. Read More.

According to the EPA, perchlorate likely contaminates the water of more than 16 million Americans. Perchlorate interferes with iodine uptake in the thyroid, which can result in reduced thyroid hormones and an impact on metabolism, physical development and cognitive development. Children and developing fetuses are the most at risk from perchlorate contamination.

Perchlorate is the only unregulated contaminant for which the EPA has attempted to set a federal drinking water standard since 1996. However, the agency has yet to propose a draft limit for this contaminant. Perchlorate in drinking water is regulated in Arizona, California, Massachusetts, New Jersey, New York and Texas. California set a public health goal of 1 part per billion for perchlorate in 2015.

Click here to read more about perchlorate.

 

15

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2018ND30ND
2019ND30ND
2020ND30ND
20210.174 ppb330.159 ppb - 0.190 ppb
20220.221 ppb330.107 ppb - 0.285 ppb
2023N/A00N/A

ppb = parts per billion

State, National, and Health Guidelines for Drinking Water

EWG Health Guideline: 1 ppb

The EWG Health Guideline of 1 ppb for perchlorate 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 hormone disruption.

ppb = parts per billion

All test results

Date Result
2018-08-06ND
2018-08-06ND
2018-08-06ND
2019-08-05ND
2019-08-05ND
2019-08-05ND
2020-08-03ND
2020-08-03ND
2020-08-03ND
2021-08-020.174 ppb
2021-08-020.190 ppb
2021-08-020.159 ppb
2022-08-010.107 ppb
2022-08-010.270 ppb
2022-08-010.285 ppb