First Steps to Microbial Product Testing

Microbial Product Testing 1.0

If you’re new to microbial testing, it can be confusing as to which test(s) are needed, necessary, or required.

“Which test do I need?”  –  Is a seemingly simple question, but the reality is that the requirements for a particular product can be complex. 

Whether the microbial testing is for antiviral, antibacterial, antifungal, antialgal, biodegradation or even microbial induced corrosion; at Situ Biosciences, the approach is always the same – understand the product first – then determine the appropriate testing.

To start the discussion: there is a foundation for testing that should be understood.  Standardized testing are methods often referred to by various agency monikers such as ASTM, ISO, AOAC, JIS, EPA, AATCC and others.  These methods are often developed by stakeholders for a particular application or need and have been adopted as the industry standard through a rigorous review process.  The scope of a respective method can be broad or narrow and the appropriateness of a test for a particular product type is often regulated by a government agency such as the EPA.

In general, the methods for the microbial products industry are to some degree evolving in parallel with new or revised test technology.  Old or new, as industries continue to develop products,  the testing requirements will continue to grow.  By contrast, quality control data, and other historic comparative data is not always compatible with new test method data types.   Although new methods are being developed, whether 1 year old or 50 years old, as long as the methods are continually validated against the product requirements and expectations, the age of the method has little impact on the quality of the test results.

Whether the product performance is for specific antibacterial end-use, or general preservation against fungi, or algae.  The test should be fit for the intended purpose of the product.

Initial testing of microbial products often does not need to mirror a given industry standard.   In fact, non-standardized internal testing is commonly used for product development or screening.  High-throughput testing and other more rapid assessment methods can both shorten the product development process and reduce the associated costs.

BUT – For a product to enter into the market with claims associated with its microbial performance – standardized testing is likely necessary for regulatory compliance.  Because of a long history of proven reliability, standard testing represents the best way to provide performance comparisons across an industry. Furthermore, regulatory agencies – such as the EPA – accept results from these standard methods as appropriate evidence to validate marketing claims about product performance.

Circling back Which test do I need?” – Again no simple answer.

It is best to assess both the formulation and the regulatory needs of a product at the beginning of the product development cycle and then devise an appropriate validation and certification plan for the product’s performance needs.

It cannot be stressed enough, the regulatory component of microbial products, including performance, product claims, and legal use – can be complicated.  There are few simple ‘one solution’ answers that govern a product category.  In addition, the regulations are continually improving to better control product safety, claims, use, and potential health, toxicity, and environmental impact.  For more information and some examples – See our Regulatory Page for examples of additional considerations.

Considerations for determining the appropriate test 

  • What product needs exist?

Discuss this with your test lab; product parameters such as; preservation, durability, toxicity, UV exposure, water exposure…etc.  all have appropriate tests or test modifications that can be performed to improve the reliability of a product.

  •  What product claims are needed?

Consumer products are different than industrial products.  This is surprisingly critical.  Most industrial applications are short term, point to point applications (discounting Microbial Induced Corrosion issues).  Consumer product applications can be medium (25 home launderings for textiles) to term (10 years for a textile or plastic in an automobile.  The test and the additive used can drastically impact the predictive use of test results.

  •  What application information can be provided?

Discuss the application with your test laboratory.  Their experience should help in fleshing out the important factors and they should be able to guide you in determining significant application issues that may direct the test requirements.

  •  Cost limitations

Having the test lab discuss their experience with different product additives can provide cost/performance parameters to help in the decision making process.  Contributing cost factors such as loss during molding can greatly influence product performance.  In addition, the chemical reactivity of some additives can contribute to higher costs due to needed secondary ‘control’ additive requirements.

  •  Manufacturing methods, or procedures

Manufacturing parameters can be critical in determining the correct additive, the correct test for the additive and the expected cost/performance profile of a given product.  Differences in manufacturing with a product such as injection molding compared to thermoforming OR coating with a two-part catalyzed resin compared to a powder coating… to name a few.

With the answers to these questions in hand, you can then discuss your objective with your laboratory personnel to better decide which tests are most appropriate, and the potential for developing or optimizing your product offering.

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