Nitrifying bacteria include the genera Nitosomonas, Nitrobacter and Nitrosococcus. They are an important group of bacteria that can be used as an indicator for the presence of organic nitrogenous material in water.  During the nitrification process, bacteria aerobically oxidize ammonium to nitrite and then further to nitrate.  Aggressive nitrifying bacteria can produce high concentrations of nitrates.  This could pose a potential health risk, particularly to infants who haven’t developed a tolerance to nitrates.  The presence of aggressive nitrifying bacteria in water may indicate contamination from a sewage system, septic tank or industrial waste.

Types of water to be tested include: potable water plumbing systems, well water.

Test Method

N-BART™ Biological Activity Reaction Test for Nitrifying Bacteria. Manufacturer: Droycon Bioconcepts Inc. Saskatchewan, Canada

Turn Around Time

5 days

Test Code


Sampling Instructions

Note: These bacteria and their affects are often associated with water in low flow areas. Sample collection will vary by source. The test is semi-quantitative; therefore, once collected, the sample should be shipped to lab within 24 hours with a cold pack. Generally, collect samples as follows:

  1. Complete SPL Chain of Custody form provided. 
  2. Use waterproof pen to label bottle with sample location, description, and date. 
  • Cooling Tower and Non-potable Water
    1. Submerge open bottle just under the surface of water to obtain ≥30 ml of sample. Avoid sediment. 
    2. Close bottle and invert to mix the sodium thiosulfate neutralizer.
  • Potable Water
    1. Turn on water (hot or cold) and immediately fill bottle to ≥30 ml.
    2. Close bottle and then invert to mix the sodium thiosulfate neutralizer.

Sample Transport 

  1. Deliver or ship samples the same day they are collected. The time from sample collection to analysis should not exceed 24 hours.
  2. Place bottles in box with insulated liner.
  3. Place completed Chain of Custody in plastic document holder and pack in box.
  4. Ship overnight Monday–Thursday only to: Special Pathogens Laboratory, 1401 Forbes Avenue, Suite 401, Pittsburgh, PA 15219

Questions? Call SPL at 412-281-5335