Scaling UP! H2O

235 The One About What A Microbiologists Wants You To Know About Legionella Testing

legionella, legionella awareness month, Michael LoewensteinI asked Michael Loewenstein on the podcast today to talk about his trailblazing presentation at AWT on Legionella Testing, and thankfully, he generously agreed to come on the podcast as my lab partner today. After listening to our cutting-edge conversation, I have a feeling you are going to want to learn more about the Cultural Method vs. the Rapid Method and submit Legionella samples to Michael for the next phase of his study so we’ve linked his contact information below. You know as well as I that when water treaters come together to share what we know, we can raise the bar for our entire industry, so I encourage everyone to further advance our industry by submitting samples as soon as they can. Buckle your seatbelts because this is going to be one groundbreaking conversation!

For those of you who missed his presentation at AWT, Michael Loewenstein is the Vice President of Scientific Consulting at Q Labs LLC in Cincinnati, OH. He earned his B.S. in Microbiology, with a research focus in Molecular Genetics and Cellular Physiology from The Ohio State University. After graduation, Michael obtained a position in Corporate R&D Microbiology at Procter & Gamble where he focused on the development and validation of rapid/alternative microbial test methods and developed and launched preservative systems across a broad range of P&G products.  

Throughout the course of his career, Michael has developed a substantial depth of expertise in “end-to-end” Microbiology – from product development and formulation through microbiological control of manufacturing, and he has published several articles on this subject. Michael worked as Site Microbiology Manager for a P&G drug manufacturing facility just prior to accepting the position with Q Labs in December 2018.  

Michael currently serves in a volunteer capacity for several professional associations, including the AOAC Microbial Contaminants Expert Review Panel, and both the Microbiology Committee and Manufacturing Hygiene Task Force of the Personal Care Products Council (PCPC). Michael is also looking forward to becoming more involved with the Cooling Water subcommittee of AWT. 


Bottom line: Michael Loewenstein is on the show to share the revolutionary results of his most recent scientific study on Legionella testing.

Your roadside friend, as you travel from client to client. 




Upcoming events [0:30]

Thinking On Water With James: Are you stuck in a rut? [4:06]

Getting to know Michael Loewenstein [6:15]

Why the “Gold Standard” Method for Legionella testing isn’t standardized  [8:50]

The new/modern Rapid Method’s capabilities [10:50]

The Cultural Method vs. Rapid Method [11:40]

Understanding Quantitative vs. Qualitative Legionella analysis [17:50]

Potential pre-treatment problems with the Cultural Method [20:50]

How COVID-19 increased public knowledge on PCR testing [ 23:08]

What you need to know when switching from the Cultural Method to the Rapid Method [24:30]

How to make a Hazard Strategy [29:00] 

Advantages to the PCR Method [30:40]

Lightning round questions [37:50]


Thinking On Water With James: Are you stuck in a rut?

In this week’s episode, we’re thinking about being stuck in a rut. Are you stuck in a rut in your industrial water treatment career? Are you running the same old pinks and blues in the same accounts day after day? If so and you feel stuck in a rut, what are you missing by just going through the motions at each account? What other water parameters should you be testing? What other value-added projects are just waiting to be done that you currently cannot see while stuck in a rut? What equipment needs to be repaired or replaced? What new things can you learn? How can you take a fresh look at your accounts, testing habits, control equipment, daily routine, and knowledge base to mix things up a little and make you an even more valuable partner for your customers? If you feel stuck in a rut, take this next week to think about it and possibly reach out to someone else within your company and network to help get you out.



“In reality, the “Gold Standard” of Legionella testing methods are not the same.” – Michael Loewenstein

“Today, the Rapid Methods can distinguish live from dead cells, they are quantitative, and can characterize the Legionella to some degree.” – Michael Loewenstein

“Modern technologies have found ways to discount the genetic materials from dead cells, so they now only count the genetic materials from live Legionella in the water sample.” – Michael Loewenstein

“PCR is much more sensitive than the Cultural Method, so it puts the water treater in a proactive position rather than reactive.” – Michael Loewenstein

“At low levels, the Cultural Method is highly variable and not particularly sensitive.” – Michael Loewenstein

“Quantitative – how much Legionella is there? vs. Qualitative – is Legionella there or not?” – Michael Loewenstein

“The limits for the Cultural Method are set semi-arbitrarily. There is nothing magic about less than 1 CFU/mL (1,000 CFU/L), except that it’s what somebody picked.” – Michael Loewenstein

“What would be great is more frequent testing and then set statistically-based action limits. Figure out for your system what is normal.” – Michael Loewenstein

“PCR far out-performed the Cultural Method for Legionella testing.” – Michael Loewenstein


Michael Loewenstein’s Presentation of Phase 1 of his method study presented at AWT:

Technical Paper



Interested in submitting Legionella samples? 

Please connect with Michael Loewenstein to help advance future studies

Phone: (513) 207-4943



LinkedIn: in/michael-loewenstein-09693944


Links Mentioned:

The Rising Tide Mastermind

Submit a Show Idea

Q Labs LLC

Procter & Gamble


Personal Care Products Council (PCPC) 

AWT (Association of Water Technologies)

Centers For Disease Control And Prevention: Toolkit

ISO 11731:2017




National GroundWater Association’s Hydrogeology of States Webinar Series: Vermont – February 9 

AWT Technical Training Seminar – Feb 23-26 in Seattle, Washington

AWT Technical Training Seminar  – March 30-April 2 in Cleveland, Ohio


Water Treatment education

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.