Scientists from 17 companies came together through a Consumer Specialty Products Association task force to advance science: Specifically, the science of preservatives used in household and institutional products.
Effective preservatives are vital to maintaining product integrity because they prevent microbial growth. The current method of evaluating how effective a preservative is, however, needs work, the members of the Microbiology Preservative Subcommittee found.
Companies use a method called Preservative Efficacy Testing (PET) to, as it sounds, evaluate a preservative’s effectiveness. PET studies determine the effective concentration of a preservative system necessary to protect a formulated product from microbial spoilage. They also demonstrate a product’s ability to remain unspoiled through its shelf-life.
Though there are similarities across company practices, there is currently no industry-wide standard for PET, the subcommittee members found. Many companies use an internal PET method and allow for a number of modifications to these methods, the subcommittee scientists found.
Modifications made include those related to the:
- Selection of microorganisms,
- Preparation of mold spore inoculum,
- Test sample quantity and containers,
- PET studies conducted internally and externally,
- Testing on undiluted vs diluted products, and
- Varying incubation periods.
“This survey clearly shows that given the number of variations seen within the industry with respect to the testing itself, a more standardized guidance for PET valuations is needed,” the scientists said when they published their survey results. Standard industry guidance is important in ensuring that all companies are evaluating preservatives as effectively, efficiently and accurately as possible.
For more information regarding this subcommittee or the divisions involved with this survey, please contact Tim Brown at firstname.lastname@example.org.
 The Microbiology Preservative Subcommittee (MPS) is part of the Cleaning Products Division of the Consumer Specialty Products Association.