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EWG's Tap Water Database — 2019 UPDATE

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Perchlorate

Newhall CWD-Newhall

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.

 

50

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2012ND80ND
2013ND80ND
2014ND70ND
2015ND100ND
2016ND80ND
2017ND90ND

ppb = parts per billion

State and national drinking water standards and health guidelines

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 Lab ID Result
2012-01-129590-006-0951ND
2012-01-129590-007-0940ND
2012-04-129590-007-1150ND
2012-04-129590-006-0830ND
2012-07-129590-006-1012ND
2012-07-129590-007-0950ND
2012-10-119590-007-1109ND
2012-10-119590-006-1100ND
2013-01-109590-007-0940ND
2013-01-109590-006-0925ND
2013-04-119590-007-0855ND
2013-04-119590-006-0835ND
2013-07-119590-007-0925ND
2013-07-119590-006-0912ND
2013-10-109590-007-1205ND
2013-10-109590-006-1140ND
2014-01-169590-007-1105ND
2014-04-109590-007-0936ND
2014-05-299590-006-0955ND
2014-07-179590-006-0815ND
2014-07-179590-007-0850ND
2014-10-139590-006-0956ND
2014-10-139590-007-1030ND
2015-01-159590-007-0920ND
2015-01-159590-006-1027ND
2015-04-239590-006-1110ND
2015-04-239590-007-1127ND
2015-04-299590-006-1120ND
2015-04-299590-007-1145ND
2015-07-169590-006-0910ND
2015-07-169590-007-0930ND
2015-10-159590-006-0916ND
2015-10-159590-007-0926ND
2016-01-079590-007-0920ND
2016-01-079590-006-0905ND
2016-04-149590-007-1045ND
2016-04-149590-006-1105ND
2016-07-219590-007-0825ND
2016-07-219590-006-0902ND
2016-10-069590-007-1110ND
2016-10-069590-006-1050ND
2017-01-129590-006-0845ND
2017-02-239590-007-1155ND
2017-04-139590-007-0911ND
2017-04-139590-007-0908ND
2017-04-139590-006-0940ND
2017-04-139590-006-0937ND
2017-07-139590-006-1010ND
2017-07-139590-007-0830ND
2017-10-199590-007-0950ND