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EWG's Tap Water Database — 2021 UPDATE

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Nitrate and nitrite

California American Water Company - Parkway

Nitrate and nitrite enter water from fertilizer runoff, septic tanks and urban runoff. These contaminants can cause oxygen deprivation for infants and increase the risk of cancer. Nitrite is significantly more toxic than nitrate. Click here to read more about nitrate.

 

45

Samples

0

Samples exceeding legal limit (MCL)

13

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014ND10ND
20151.18 ppm228ND - 7.30 ppm
2016N/A00N/A
2017ND10ND
20180.510 ppm215ND - 3.30 ppm
2019N/A00N/A

ppm = parts per million

State and national drinking water standards and health guidelines

EWG Health Guideline 0.14 ppm

The health guideline of 0.14 parts per million, or ppm, for nitrate and nitrite is based on the equivalent health guideline for nitrate, as defined in a peer-reviewed scientific study by EWG. This guideline represents a one-in-one-million annual cancer risk level.

EPA Maximum Contaminant
Level (MCL) 10 ppm

ppm = parts per million

All test results

Date Lab ID Result
2014-08-121225-017-1115ND
2015-07-151225-022-1110ND
2015-07-151225-044-1155ND
2015-07-151225-043-10150.500 ppm
2015-07-151225-033-1205ND
2015-07-151225-032-1020ND
2015-07-151225-025-1225ND
2015-07-151225-023-1135ND
2015-07-151225-002-09402.40 ppm
2015-07-151225-021-1040ND
2015-07-151225-015-08402.30 ppm
2015-07-151225-014-10303.70 ppm
2015-07-201225-013-08452.00 ppm
2015-07-201225-024-1150ND
2015-07-201225-008-09303.80 ppm
2015-07-201225-034-1130ND
2015-07-201225-042-1115ND
2015-07-201225-006-0950ND
2015-07-201225-003-10307.30 ppm
2015-07-221225-018-0925ND
2015-07-221225-011-10453.90 ppm
2015-07-221225-026-1000ND
2015-07-291225-016-1015ND
2017-08-151225-017-1012ND
2018-08-081233-002-11002.20 ppm
2018-08-091233-017-0835ND
2018-08-091233-016-0930ND
2018-08-091233-006-1140ND
2018-08-141233-008-11053.30 ppm
2018-08-141233-025-0740ND
2018-08-141233-023-0830ND
2018-08-141233-022-0910ND
2018-08-141233-011-09001.40 ppm
2018-08-141233-021-1005ND
2018-08-141233-015-10202.10 ppm
2018-08-141233-013-11451.70 ppm
2018-08-151233-024-1250ND
2018-08-151233-026-1210ND
2018-08-151233-032-0905ND
2018-08-151233-034-1335ND
2018-08-151233-042-1325ND
2018-08-151233-018-1210ND
2018-08-151233-043-0855ND
2018-08-161233-033-0755ND
2018-08-161233-044-0745ND