21 named for nitrate itself on the list.
Per the state list or a state web page. Call to confirm.
Located outside Arizona but on its list.
USGS estimate for Arizona.
How many labs test for nitrate in Arizona
21 labs on Arizona's official drinking-water lab list are certified to test for nitrate. All 21 are named for nitrate on the list. The Arizona list does not say which labs take samples from homeowners, so call a lab before you send one. 12 are located outside Arizona.
The list is published by the Arizona Department of Health Services (ADHS) - Bureau of State Laboratory Services, Office of Laboratory Licensure & Certification (Environmental Laboratory Licensure). List version on file: current as of Saturday, November 7, 2026. Fetched 2026-11-07 (UTC).
Arizona labs certified for nitrate
| Lab | Location | Nitrate certification | Public samples | Cert. expiry |
|---|---|---|---|---|
| A & B Environmental Services, Inc | Houston, TX | Named on the official list | Public samples: ask the lab | Not on the list |
| A & B Labs Arizona Inc. | Tempe, AZ | Named on the official list | Public samples: ask the lab | Not on the list |
| ACZ Laboratories, Inc. | Steamboat Springs, CO | Named on the official list | Public samples: ask the lab | Not on the list |
| AGAT Laboratories | Mississauga, ON | Named on the official list | Public samples: ask the lab | Not on the list |
| AGAT Laboratories | Tempe, AZ | Named on the official list | Public samples: ask the lab | Not on the list |
| Aquatic Consulting & Testing, Inc. | Tempe, AZ | Named on the official list | Public samples: ask the lab | Not on the list |
| Eurofins Environment Testing Southwest | Phoenix, AZ | Named on the official list | Public samples: ask the lab | Not on the list |
| Eurofins Lancaster Laboratories Environment Testing, LLC | Lancaster, PA | Named on the official list | Public samples: ask the lab | Not on the list |
| Eurofins Pomona | Pomona, CA | Named on the official list | Public samples: ask the lab | Not on the list |
| Eurofins South Bend | South Bend, IN | Named on the official list | Public samples: ask the lab | Not on the list |
| Inner Basin Environmental, LLC | Flagstaff, AZ | Named on the official list | Public samples: ask the lab | Not on the list |
| Legend Technical Services of Arizona, Inc. DBA Legend Analytical | Phoenix, AZ | Named on the official list | Public samples: ask the lab | Not on the list |
| Mohave Environmental Labs | Bullhead City, AZ | Named on the official list | Public samples: ask the lab | Not on the list |
| Motzz Laboratory, Inc. | Phoenix, AZ | Named on the official list | Public samples: ask the lab | Not on the list |
| National Testing Laboratories, LTD. | Ypsilanti, MI | Named on the official list | Public samples: ask the lab | Not on the list |
| Pace Analytical National Center for Testing & Innovation | Mt. Juliet, TN | Named on the official list | Public samples: ask the lab | Not on the list |
| Pace Analytical Services, LLC. - Minneapolis MN | Minneapolis, MN | Named on the official list | Public samples: ask the lab | Not on the list |
| SGS North America Inc. - Dayton | Dayton, NJ | Named on the official list | Public samples: ask the lab | Not on the list |
| SGS North America Inc. - Scott | Scott, LA | Named on the official list | Public samples: ask the lab | Not on the list |
| Turner Laboratories, Inc. | Tucson, AZ | Named on the official list | Public samples: ask the lab | Not on the list |
| WECK Laboratories, Inc. | City of Industry, CA | Named on the official list | Public samples: ask the lab | Not on the list |
How the Arizona list marks public samples (whole list). Not stated per lab. ADHS's private-well pamphlet says independent laboratories can test private well water and points well owners to this list; it does not say which labs take samples from well owners.
Before you send a sample, call the lab to confirm it is currently certified for the exact test and method, that it accepts samples from homeowners, and how to collect and ship them. Status can change between list updates.
Why test for nitrate in Arizona
Nitrate has no taste or smell, and a lab report can state the same water in two units that differ by a factor of 4.43. Read our nitrate explainer.
EPA advises private-well owners to test every year for total coliform bacteria, nitrates, total dissolved solids and pH. [1]
Arizona guidance that mentions nitrate:
- The Arizona Department of Health Services (ADHS) well owner guide lists a testing schedule. Test all new wells for arsenic, total coliform bacteria, fluoride, lead, nitrates, total dissolved solids (TDS) and uranium. Then test once a year for total coliform bacteria and nitrates, and every 5 years for arsenic, fluoride and uranium. Also test when there are known well water problems in your area, after problems near your well (flooding, wildfire, land disturbances, nearby waste disposal sites), when the water's taste, color or odor changes, or if anyone in your family has an unexplained illness. [2]
About 218,170 people in Arizona used private wells in 2015, by the USGS estimate of people on domestic self-supplied water. [3] Federal limits are written for public water systems, not private wells, so testing is up to the owner.
For tests that depend on your home (farms nearby, old plumbing, a new baby), use the which-tests checklist. When results arrive, check your numbers against EPA's limits. State guidance, county data and every lab: Arizona.
Other tests in Arizona
- U.S. EPA, Protect your home's water
- Arizona Department of Health Services, Office of Environmental Health, Protect Your Health: a guide for private well owners in Arizona (no date printed)
- USGS, Estimated use of water in the United States, county-level data for 2015 (Dieter et al., ver. 2.0, 2018)
- ADHS Safe Drinking Water Commercial Lab List (List of Arizona Certified Commercial Drinking Water Laboratories) (official list)
ADHS Safe Drinking Water Commercial Lab List (List of Arizona Certified Commercial Drinking Water Laboratories).
Official source