Know Your Environment. Protect Your Health.

Nitrate

Ayer DPW Water Division

Nitrate, a fertilizer chemical, frequently contaminates drinking water due to agricultural and urban runoff, and discharges from municipal wastewater treatment plants and septic tanks. Excessive nitrate in water can cause oxygen deprivation in infants and increase the risk of cancer. Click here to read more about nitrate.

 

42

Samples

0

Samples exceeding legal limit (MCL)

29

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.231 ppm87ND - 0.400 ppm
20190.393 ppm660.280 ppm - 0.470 ppm
20200.370 ppm76ND - 0.850 ppm
20210.286 ppm75ND - 0.720 ppm
20220.309 ppm76ND - 0.820 ppm
20230.319 ppm76ND - 0.920 ppm

ppm = parts per million

State, National, and Health Guidelines for Drinking Water

EWG Health Guideline: 0.14 ppm

The EWG 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

The legal limit for nitrate, established in 1962, was developed to protect infants from acute methemoglobinemia, a life-threatening disorder of oxygen transport in the body. This limit does not fully protect against the risk of cancer and harm to the developing fetus.

ppm = parts per million

All test results

Date Result
2018-02-08ND
2018-02-120.0500 ppm
2018-06-130.170 ppm
2018-06-130.400 ppm
2018-06-130.0700 ppm
2018-06-130.400 ppm
2018-06-130.380 ppm
2018-06-130.380 ppm
2019-04-230.470 ppm
2019-04-230.400 ppm
2019-04-230.400 ppm
2019-04-230.470 ppm
2019-04-230.280 ppm
2019-04-230.340 ppm
2020-05-27ND
2020-05-270.420 ppm
2020-05-270.210 ppm
2020-05-270.250 ppm
2020-05-270.380 ppm
2020-05-270.480 ppm
2020-12-070.850 ppm
2021-06-09ND
2021-06-090.300 ppm
2021-06-090.430 ppm
2021-06-090.720 ppm
2021-06-090.120 ppm
2021-06-09ND
2021-06-090.430 ppm
2022-04-250.0600 ppm
2022-04-250.520 ppm
2022-04-250.820 ppm
2022-04-250.430 ppm
2022-04-25ND
2022-04-250.250 ppm
2022-04-250.0800 ppm
2023-05-020.210 ppm
2023-05-02ND
2023-05-020.920 ppm
2023-05-020.530 ppm
2023-05-020.110 ppm
2023-06-130.400 ppm
2023-06-130.0600 ppm