Tools & Tips for Estimating your Environmental Monitoring Costs

New to environmental monitoring? Don't have much money to spend or an internal laboratory? Well, you better sit down for this.

Regardless of company size, sampling and testing requires a significant investment of money, time and energy. So how much should you expect to spend? The answer is complicated, but our PEM Calculator is a good place to start.


Additional Costs to Consider When Preparing a PEM Estimate

Routine environmental testing (“Not For Cause”)

In FDA's draft guidance "Control of Listeria monocytogenes in Ready-To-Eat Foods", FDA recommends "that even the smallest processors collect samples from at least 5 sites of FCS (Food Contact Surfaces) and 5 sites of non-FCS (non-Food Contact Surfaces) on each production line for RTE foods" (p.36).

A minimum of 10 swabs at FDA's recommended weekly sampling frequency for high risk foods (i.e. foods that are capable of supporting Listeria growth) totals 520 swabs per year. If you're lucky, your lab may charge as little as $20/swab for Listeria species testing. Assuming you have one production line and find zero presence of Listeria species in your environment, the total annual cost of lab services (not including equipment and materials costs) is around $10,400.

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The above is a very liberal estimate given:

  • Most companies may swab more than 10 surfaces per week

  • Companies are likely to face higher lab costs than $20/swab as well as ancillary expenses (e.g. equipment, materials, consulting and training fees)

  • The estimate does not factor in follow-up costs associated with a positive result (“For Cause” sampling, covered below)

Fire Fighting (“For Cause”) Sampling and Testing

When a sample tests positive (a result known as a “presumptive positive”), the company must:

  1. Determine whether or not the positive indicates the real presence of the target organism at the swab site(s) or if it is a "false positive" (one must assume the result is positive unless proven otherwise); AND

  2. If the target organism is assumed or demonstrated to be present, to take appropriate action, which can vary depending on the type of organism, surface, etc. In other words, you must have a plan for corrective action.

For Cause testing can increase expenses by orders of magnitude, so best to be prepared. To give you an idea of what For Cause testing entails, a good starting point is John Butts’ article “Seek & Destroy: Identifying and Controlling Listeria monocytogenes Growth Niches.”

Total Cost of Environmental Sampling (“For Cause” and “Not For Cause”):

So back to the original question: how much does a PEM program cost? It will depend on your product, facility, and numerous other factors. Two things are for sure:

  • Assume you will find positives

  • Sampling and crisis management (and crisis preparedness) come at a significant price tag, one which can be substantially diminished through due diligence and preparedness, but never eliminated.

Find a Laboratory

Looking for a lab or just trying to get quotes? Food Safety Guides put together a Google Map of the U.S.'s major food laboratories as well as a few local, ISO 17025 accredited labs. Click on the image below, then click sites near you to get contact information for the lab of your choice.