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EWG's Tap Water Database — 2021 UPDATE

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Nitrate

Honolulu-Windward-Pearl Harbor

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.

MORE ABOUT THIS CONTAMINANT

 

316

Samples

0

Samples exceeding legal limit (MCL)

288

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
20140.456 ppm4947ND - 2.40 ppm
20150.451 ppm5552ND - 2.30 ppm
20160.438 ppm5048ND - 1.80 ppm
20170.440 ppm5350ND - 1.60 ppm
20180.451 ppm5452ND - 1.80 ppm
20190.427 ppm5550ND - 1.40 ppm

ppm = parts per million

State and national drinking water standards and health guidelines

EWG Health Guideline 0.14 ppm

The EWG Health Guideline of 0.14 ppm for nitrate was defined by EWG . This health guideline protects against cancer and harm to fetal growth and development.

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 Lab ID Result
2014-04-032014040403840.540 ppm
2014-04-032014040403850.380 ppm
2014-04-032014040403860.250 ppm
2014-04-032014040403870.410 ppm
2014-04-032014040403880.600 ppm
2014-04-03201404040389ND
2014-04-032014040403900.640 ppm
2014-04-032014040403910.330 ppm
2014-04-032014040403920.310 ppm
2014-04-032014040403930.160 ppm
2014-04-032014040403940.190 ppm
2014-04-102014041202920.550 ppm
2014-04-102014041202931.40 ppm
2014-04-102014041202941.000 ppm
2014-04-102014041202950.720 ppm
2014-04-102014041202960.600 ppm
2014-04-172014041802450.470 ppm
2014-04-172014041802460.600 ppm
2014-04-172014041802470.270 ppm
2014-04-172014041802480.390 ppm
2014-04-172014041802490.810 ppm
2014-04-172014041802500.460 ppm
2014-04-172014041802510.290 ppm
2014-04-172014041802520.310 ppm
2014-04-172014041802530.510 ppm
2014-04-172014041802540.580 ppm
2014-04-212014042203290.970 ppm
2014-04-212014042203300.450 ppm
2014-04-212014042203310.460 ppm
2014-04-222014042306100.440 ppm
2014-04-222014042306110.1000 ppm
2014-04-222014042306120.170 ppm
2014-04-222014042306130.390 ppm
2014-04-232014042402540.480 ppm
2014-04-232014042402550.320 ppm
2014-04-232014042402560.210 ppm
2014-04-232014042402570.140 ppm
2014-04-242014042503250.320 ppm
2014-04-242014042503260.310 ppm
2014-04-242014042503270.160 ppm
2014-04-242014042503280.170 ppm
2014-04-242014042503290.220 ppm
2014-04-28201404290638ND
2014-04-282014042906390.210 ppm
2014-04-292014043006280.190 ppm
2014-04-292014043006290.250 ppm
2014-05-072014050803772.40 ppm
2014-07-222014072306700.920 ppm
2014-08-202014082201690.290 ppm
2015-02-102015021103970.440 ppm
2015-02-112015021202810.380 ppm
2015-04-072015040804500.340 ppm
2015-04-072015040804510.320 ppm
2015-04-082015040901110.480 ppm
2015-04-082015040901120.480 ppm
2015-04-132015041401360.980 ppm
2015-04-132015041401370.600 ppm
2015-04-142015041502511.50 ppm
2015-04-152015041603510.500 ppm
2015-04-152015041603520.510 ppm
2015-04-152015041603580.240 ppm
2015-04-152015041603590.190 ppm
2015-04-152015041603600.180 ppm
2015-04-162015041700650.640 ppm
2015-04-162015041700680.1000 ppm
2015-04-202015042102820.400 ppm
2015-04-202015042102830.820 ppm
2015-04-212015042202410.470 ppm
2015-04-212015042202420.580 ppm
2015-04-212015042202430.840 ppm
2015-04-212015042202440.300 ppm
2015-04-212015042202450.660 ppm
2015-04-222015042303030.430 ppm
2015-04-222015042303040.250 ppm
2015-04-222015042303080.250 ppm
2015-04-272015042800990.300 ppm
2015-04-272015042801001.000 ppm
2015-04-282015042903180.300 ppm
2015-04-282015042903190.300 ppm
2015-04-282015042903200.490 ppm
2015-04-282015042903210.1000 ppm
2015-04-282015042903220.180 ppm
2015-04-282015042903380.540 ppm
2015-04-282015042903390.610 ppm
2015-04-292015043000560.320 ppm
2015-04-292015043000570.570 ppm
2015-04-302015050100740.190 ppm
2015-05-042015050500690.320 ppm
2015-05-052015050601110.440 ppm
2015-05-05201505060137ND
2015-05-052015050601410.720 ppm
2015-05-052015050601430.280 ppm
2015-05-052015050601440.430 ppm
2015-05-062015050702390.400 ppm
2015-05-062015050702400.230 ppm
2015-05-062015050702410.170 ppm
2015-05-112015051206360.210 ppm
2015-05-11201505120637ND
2015-05-12201505130586ND
2015-05-182015051902390.540 ppm
2015-06-092015061001000.200 ppm
2015-08-192015082004810.520 ppm
2015-10-202015102101740.270 ppm
2015-12-292015123002172.30 ppm
2016-02-100.380 ppm
2016-04-061.000 ppm
2016-04-070.960 ppm
2016-04-070.730 ppm
2016-04-070.520 ppm
2016-04-070.290 ppm
2016-04-120.480 ppm
2016-04-120.570 ppm
2016-04-120.570 ppm
2016-04-120.470 ppm
2016-04-120.560 ppm
2016-04-120.460 ppm
2016-04-120.310 ppm
2016-04-120.320 ppm
2016-04-120.320 ppm
2016-04-140.940 ppm
2016-04-140.580 ppm
2016-04-140.180 ppm
2016-04-140.440 ppm
2016-04-140.360 ppm
2016-04-140.450 ppm
2016-04-140.210 ppm
2016-04-140.180 ppm
2016-04-140.250 ppm
2016-04-180.400 ppm
2016-04-180.1000 ppm
2016-04-180.410 ppm
2016-04-190.350 ppm
2016-04-190.220 ppm
2016-04-200.180 ppm
2016-04-200.170 ppm
2016-04-210.530 ppm
2016-04-210.320 ppm
2016-04-21ND
2016-04-21ND
2016-04-250.300 ppm
2016-04-260.470 ppm
2016-04-260.460 ppm
2016-05-030.260 ppm
2016-05-040.270 ppm
2016-05-040.860 ppm
2016-05-040.420 ppm
2016-05-050.160 ppm
2016-05-160.770 ppm
2016-05-160.600 ppm
2016-05-160.610 ppm
2016-06-200.320 ppm
2016-06-200.130 ppm
2016-07-071.80 ppm
2016-10-310.260 ppm
2017-02-141.60 ppm
2017-04-040.130 ppm
2017-04-040.130 ppm
2017-04-050.540 ppm
2017-04-050.540 ppm
2017-04-120.930 ppm
2017-04-121.20 ppm
2017-04-120.440 ppm
2017-04-120.380 ppm
2017-04-180.560 ppm
2017-04-180.390 ppm
2017-04-19ND
2017-04-190.220 ppm
2017-04-200.520 ppm
2017-04-200.410 ppm
2017-04-201.60 ppm
2017-04-200.430 ppm
2017-04-200.450 ppm
2017-04-200.290 ppm
2017-04-200.270 ppm
2017-04-270.630 ppm
2017-05-020.200 ppm
2017-05-020.180 ppm
2017-05-020.120 ppm
2017-05-030.450 ppm
2017-05-040.520 ppm
2017-05-040.900 ppm
2017-05-040.700 ppm
2017-05-04ND
2017-05-04ND
2017-05-100.260 ppm
2017-05-100.810 ppm
2017-05-100.390 ppm
2017-05-110.380 ppm
2017-05-110.710 ppm
2017-05-110.320 ppm
2017-05-170.180 ppm
2017-05-170.240 ppm
2017-05-180.490 ppm
2017-05-230.180 ppm
2017-05-230.370 ppm
2017-05-230.310 ppm
2017-05-230.360 ppm
2017-05-230.290 ppm
2017-05-230.170 ppm
2017-05-240.320 ppm
2017-05-250.320 ppm
2017-05-310.690 ppm
2017-06-060.340 ppm
2017-06-070.610 ppm
2017-06-080.160 ppm
2017-06-140.510 ppm
2017-11-070.180 ppm
2018-02-202018022201180.130 ppm
2018-03-282018033003060.960 ppm
2018-04-042018040507251.60 ppm
2018-04-092018041205840.430 ppm
2018-04-092018041205850.210 ppm
2018-04-092018041205820.490 ppm
2018-04-092018041205830.490 ppm
2018-04-092018041205870.390 ppm
2018-04-092018041205880.450 ppm
2018-04-092018041205861.000 ppm
2018-04-102018041205800.620 ppm
2018-04-10201804120579ND
2018-04-102018041205770.490 ppm
2018-04-102018041205780.580 ppm
2018-04-102018041205810.700 ppm
2018-04-112018041303620.150 ppm
2018-04-112018041304020.860 ppm
2018-04-112018041304060.300 ppm
2018-04-112018041304040.310 ppm
2018-04-112018041304030.660 ppm
2018-04-112018041304050.490 ppm
2018-04-112018041304010.540 ppm
2018-04-172018042300430.520 ppm
2018-04-172018042300440.320 ppm
2018-04-172018042300450.480 ppm
2018-04-172018042300420.320 ppm
2018-04-172018041810830.550 ppm
2018-04-182018042005700.380 ppm
2018-04-182018042005670.570 ppm
2018-04-182018042005680.710 ppm
2018-04-242018042604471.80 ppm
2018-04-242018042604410.250 ppm
2018-04-242018042604430.250 ppm
2018-04-242018042604420.190 ppm
2018-04-242018042604440.380 ppm
2018-04-242018042604450.280 ppm
2018-04-242018042604460.330 ppm
2018-04-242018042604400.410 ppm
2018-04-242018042604481.000 ppm
2018-04-262018043005010.470 ppm
2018-05-012018050401450.180 ppm
2018-05-012018050401410.160 ppm
2018-05-01201805040143ND
2018-05-012018050401420.200 ppm
2018-05-012018050401460.180 ppm
2018-05-012018050401440.320 ppm
2018-05-022018050307140.240 ppm
2018-05-022018050307150.160 ppm
2018-05-302018052305840.130 ppm
2018-06-122018061403720.490 ppm
2018-07-252018072605790.310 ppm
2018-08-072018081002150.170 ppm
2018-09-192018092006060.560 ppm
2018-09-192018092006070.170 ppm
2019-01-282019012901180.160 ppm
2019-03-142019031503460.340 ppm
2019-04-012019040202371.30 ppm
2019-04-022019040401720.520 ppm
2019-04-082019040904330.990 ppm
2019-04-102019041101390.470 ppm
2019-04-102019041101401.40 ppm
2019-04-102019041102000.250 ppm
2019-04-102019041101380.330 ppm
2019-04-102019041102020.370 ppm
2019-04-102019041101990.410 ppm
2019-04-102019041102010.430 ppm
2019-04-102019041102040.610 ppm
2019-04-102019041102031.000 ppm
2019-04-152019041601280.300 ppm
2019-04-152019041601260.250 ppm
2019-04-152019041601270.320 ppm
2019-04-152019041601250.400 ppm
2019-04-162019041701770.180 ppm
2019-04-162019041701790.240 ppm
2019-04-162019041701780.190 ppm
2019-04-162019041702050.320 ppm
2019-04-162019041702060.470 ppm
2019-04-162019041701820.170 ppm
2019-04-162019041701800.220 ppm
2019-04-162019041701810.180 ppm
2019-04-162019041701760.180 ppm
2019-04-172019041802090.400 ppm
2019-04-172019041802100.210 ppm
2019-04-172019041802010.490 ppm
2019-04-172019041802020.480 ppm
2019-04-22201904230220ND
2019-04-242019042502510.940 ppm
2019-04-242019042502500.280 ppm
2019-04-242019042502480.710 ppm
2019-04-242019042502490.460 ppm
2019-04-252019042602920.470 ppm
2019-04-252019042602930.470 ppm
2019-04-292019043002820.160 ppm
2019-04-292019043002270.620 ppm
2019-04-292019043002830.170 ppm
2019-04-29201904300226ND
2019-04-292019043002240.520 ppm
2019-04-292019043002250.570 ppm
2019-05-012019050202570.580 ppm
2019-05-012019050202580.650 ppm
2019-05-022019050301330.590 ppm
2019-05-022019050301340.730 ppm
2019-07-10201907110442ND
2019-09-18201909190159ND
2019-09-182019091906440.330 ppm
2019-09-252019092606080.210 ppm
2019-10-292019103004610.920 ppm
2019-11-192019112003240.550 ppm
2019-12-26201912270120ND