CTFA M-5 Method Summary

It is important in preservative challenge testing to consider the typical use of the finished product and to test them in their finished state. For example, nonwoven substrates such as presaturated wipes or towelettes, should be tested in the wipe form and not on just the add-on solution. The CTFA M-5 guidelines are designed for personal care products such as wipes or towelettes that contain aqueous-based add-on solutions.

A summary of the CTFA M-5 method is described below:

CTFA M-4 Method Summary

Preservative challenge testing for eye area cosmetics is extremely important to ensure the safety of your consumers. The eyes are a common area for infection by microorganisms such as Pseudomonas species that can be found in cosmetics that are not properly preserved. CTFA M-4 is a guideline for preservative challenge testing of eye area cosmetics.

A summary of the CTFA M-4 method is described below:

CTFA M-3 Method Summary

Once it has been determined that products are free from harmful microorganisms, it is important to ensure that they remain free from contamination during manufacturing consumer use. That is accomplished through challenge testing the formula with known microorganisms to verify that if the products become contaminated, the preservative system is sufficient to inhibit the growth of the microorganisms and spoilage.

Aerobic Plate Count Test: Fungi

Yeast and molds are types of fungal cells that can cause various degrees of  deterioration and decomposition of cosmetics and personal care products. Since yeast and molds are ubiquitous (occuring everywhere) in nature just as bacteria are, cosmetics and personal care products are just as susceptible to fungal contamination as they are to bacterial contamination.