Pseudomonas aeruginosa is a bacterium that can be found in various types of moist environments.  This opportunistic pathogen is commonly associated with hospital-acquired infection, most notably in immunocompromised individuals. Pseudomonas aeruginosa accounts for 10% of all hospital-acquired infections and is the second most frequently recovered pathogen from intensive care units. Healthy individuals can acquire eye, ear and skin infections as well, through contaminated recreational waters. Types of water that may be tested include: potable water where high risk patients are found, swimming pools, spas and hot tubs.

Test Method 

Filter concentration method using M-PA-C selective media, incubation 41.5°C + 0.5°C for 48 to 72 h.  Modification of the ASTM International Standard Test Method for the Isolation and Enumeration of Pseudomonas aeruginosa from water [D 5246-92 (Reapproved 2004)] with the addition of direct plating in the event of high concentrations of the organism

Turn Around Time  

2–10 days

Test Code


Sampling Instructions

Prior to collecting samples for potable water or for swimming pools, spas or hot tubs:

  1. Complete SPL Chain of Custody Test Request form. 
  2. Use waterproof pen to label bottle with sample location, description, and date.

The sample volume is ≥120 mL and should be collected as follows:

Potable Water

Turn on hot water and immediately fill the bottle. Close bottle and invert to mix neutralizer.

Swimming Pools, Spas, Whirlpools or Hot Tubs 

  1. Collect sample by removing cap and holding at an angle of 45°. Fill in one slow sweep down through the water with the mouth of the bottle always ahead of the hand.
  2. Fill the bottle (≥120 mL). Be careful to retain the sodium thiosulfate neutralizer in bottle.
  3. Replace cap and mix.

Sample Transport

  1. Ship the same day samples are collected for receipt in laboratory. The time from sample collection to analysis should not exceed 30 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

Samples received on Saturday will not be processed.

Questions? Call 412-281-5335