If you’re conducting USP <61>, <62>, or <71> microbiological testing, suitability is required to be compliant. At Eurofins’ New Jersey laboratory in North Brunswick, our microbiology experts are here to help clients navigate this critical but often overlooked step in product testing.

Suitability testing ensures that your testing method can detect target microorganisms in the presence of your product. Without it, you risk producing false negative results—which can lead to serious compliance and regulatory consequences, and public health risks.

In this blog, we’ll explore:

• What suitability testing is and when it’s required
• Common misconceptions and risks of skipping it
• Why Eurofins North Brunswick laboratory is trusted by top manufacturers to get it right, the first time!

Suitability testing is a method verification required by the USP. It confirms that the testing method used for release testing can recover microorganisms in the presence of a specific product or formulation. Simply put, it provides demonstrated scientific evidence!

This step is essential for:

• Raw materials
• Excipients
• Finished products
• Products with new formulations
• Any material undergoing a manufacturing or ingredient or process change

Any time you’re introducing a new product, changing a formulation, or submitting samples that have not been previously validated, suitability testing should be performed before routine microbiology testing begins.

Additionally, if you’re using raw materials or active pharmaceutical ingredients (APIs) across multiple product types, each final finished product still needs its own suitability verification.

Here’s the truth: not every testing lab will mention suitability testing. And not every client knows to ask about it.

In many cases, companies send samples in for microbial testing assuming it’s plug-and-play. But without suitability testing, results may be invalid. This is especially true for clients without an in-house microbiologist or regulatory SME.

At Eurofins North Brunswick, our team not only performs suitability testing with scientific rigor—we educate our clients on when and why it’s needed.

Most labs will claim they have excellent scientists and great technology—but that’s not enough. What sets Eurofins apart is our commitment to:

1. Proactive Regulatory Guidance

We don’t wait for clients to ask. If you submit a sample that requires suitability testing, we’ll flag it. We explain the regulatory requirement clearly, and we help you understand how skipping this step could impact your product’s safety, your compliance to regulatory standards, and ultimately your business.

2. Hands-On Client Education

Many clients come to us not knowing why a suitability testing is required, andhat’s okay! Our team—especially the experts leading our North Brunswick Laboratory—walks clients through the process, answering questions and tailoring testing recommendations to their specific formulations and goals.

3. Risk Prevention Thorough Method Validation

Skipping suitability testing is a gamble. It may save money upfront, but it creates significant downstream risk:

• False negatives can result in unsafe products reaching the market.
• FDA inspections may uncover noncompliance and delay product approvals.
• Repeat testing and recalls can be far more expensive than doing it right the first time.

At Eurofins, our team ensures every sample goes through the proper evaluation so you can be confident in your test results—and your regulatory readiness.

Unfortunately, we’ve seen it happen. A company skips the suitability phase, goes through microbial testing, and assumes everything is fine—until:

• A regulatory inspection identifies missing validations
• A product fails in-market testing
• A batch recall becomes necessary due to undetected contamination

Don’t wait for a crisis to realize something was missed. Suitability testing is your assurance that your method works for your product.

Whether or not you’ve heard of it before, suitability testing is a compliance requirement under USP <61>, <62>, and <71>. More importantly, it’s your safety net against false negatives during routine testing.

If you’re not sure whether you need suitability testing—ask us. The Eurofins North Brunswick team is here to guide you through the process, protect your timelines, and ensure you meet all microbiological quality standards with confidence.

Contact us today to determine whether suitability testing is required for your product—and how we can help you get started the right way.

Eurofins | 30 Silverline Drive, North Brunswick, NJ 08902
(732) 253-7373 x111