Know Your Environment. Protect Your Health.

Perchlorate

West San Martin Water Works Inc.

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.

 

52

Samples

0

Samples exceeding legal limit (MCL)

29

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.879 ppb2011ND - 2.50 ppb
20191.33 ppb73ND - 4.80 ppb
20201.97 ppb64ND - 5.00 ppb
20213.42 ppb54ND - 5.20 ppb
20223.62 ppb662.40 ppb - 5.40 ppb
20230.363 ppb82ND - 1.50 ppb

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 Lab ID Result
2018-02-08CA4300543_004_004-2018020815000.870 ppb
2018-02-23CA4300543_004_004-2018022310061.30 ppb
2018-03-09CA4300543_004_004-2018030910041.20 ppb
2018-03-21CA4300543_004_004-2018032110051.30 ppb
2018-04-06CA4300543_004_004-201804061032ND
2018-04-19CA4300543_004_004-2018041915301.70 ppb
2018-05-03CA4300543_004_004-2018050313051.30 ppb
2018-05-18CA4300543_004_004-2018051810021.60 ppb
2018-05-24CA4300543_002_002-201805241130ND
2018-06-05CA4300543_004_004-201806051231ND
2018-06-06CA4300543_002_002-201806061200ND
2018-06-21CA4300543_004_004-2018062113002.40 ppb
2018-07-05CA4300543_004_004-201807051455ND
2018-07-19CA4300543_004_004-2018071911312.50 ppb
2018-08-13CA4300543_004_004-2018081311011.80 ppb
2018-09-05CA4300543_002_002-201809051230ND
2018-09-13CA4300543_004_004-201809131000ND
2018-11-08CA4300543_004_004-2018110811001.60 ppb
2018-12-05CA4300543_002_002-201812051255ND
2018-12-11CA4300543_004_004-201812111032ND
2019-01-14CA4300543_004_004-2019011412171.50 ppb
2019-03-05CA4300543_002_002-201903051405ND
2019-04-15CA4300543_004_004-2019041509594.80 ppb
2019-06-24CA4300543_002_002-201906241415ND
2019-09-16CA4300543_002_002-201909161755ND
2019-09-19CA4300543_010_010-201909191240ND
2019-10-02CA4300543_004_004-2019100213333.00 ppb
2020-01-07CA4300543_004_004-2020010711301.40 ppb
2020-04-01CA4300543_004_004-2020040113501.30 ppb
2020-07-29CA4300543_004_004-2020072908054.10 ppb
2020-08-12CA4300543_010_010-202008120800ND
2020-08-12CA4300543_002_002-202008120750ND
2020-12-10CA4300543_004_004-2020121008055.00 ppb
2021-01-13CA4300543_004_004-202101130815ND
2021-04-14CA4300543_004_004-2021041409153.90 ppb
2021-07-07CA4300543_004_004-2021070708504.70 ppb
2021-10-04CA4300543_004_004-2021100409105.20 ppb
2021-10-20CA4300543_004_004-2021102012583.30 ppb
2022-01-19CA4300543_010_010-2022011909553.00 ppb
2022-01-19CA4300543_004_004-2022011910052.40 ppb
2022-04-13CA4300543_004_004-2022041309402.60 ppb
2022-07-18CA4300543_004_004-2022071811455.40 ppb
2022-09-13CA4300543_010_010-2022091312404.10 ppb
2022-10-05CA4300543_004_004-2022100511004.20 ppb
2023-01-18CA4300543_010_010-202301181030ND
2023-03-13CA4300543_004_004-202303131200ND
2023-04-05CA4300543_010_010-202304051205ND
2023-06-19CA4300543_004_004-202306191115ND
2023-10-04CA4300543_010_010-202310041020ND
2023-12-06CA4300543_004_004-202312060815ND
2023-12-13CA4300543_002_002-2023121311351.50 ppb
2023-12-18CA4300543_002_002-2023121808001.40 ppb