Microbiological Analysis for Cosmetics: Protecting Consumer Health

The analysis of cosmetics is of great importance in terms of consumer health. A cosmetic product must be microbiologically safe for the consumer.

For the safety of cosmetics, microbiological analyzes show whether bacteria, mold and yeast growth are present in a cosmetic product. There may be total microorganisms within certain limits in cosmetic products, but there should be no pathogenic bacteria.

Cosmetics must have protective systems for product safety in terms of microbiology. The effectiveness of these protective systems against microorganisms should be demonstrated by protective effectiveness tests.

The presence of pathogenic microorganisms in cosmetics can cause health problems. Especially if microorganisms such as Escherichia coli, Candida albicans, and Pseudomonas aeruginosa reproduce in cosmetic products, it can cause infections and other health problems. Therefore, performing microbiological analysis of cosmetics is essential to protect the health of consumers. Manufacturers also use microbiological analysis to ensure their products' quality and determine their products' shelf life.

Manufacturers are advised to regularly perform microbiological analyses to ensure that their products are produced under hygienic conditions. It is recommended that the tests be performed in an accredited laboratory.

It is strongly recommended to include the use of ISO Standards for Microbiological Testing of Cosmetics. 

Challenge test can test the efficacy of antimicrobial preservation in cosmetics. 

Cosmetics must be microbiologically controlled.

Enumeration and detection of aerobic mesophilic bacteria

This standard provides guidance for the enumeration and detection of mesophilic bacteria Determination of Aerobic Bacteria in Cosmetics by Counting Colonies on agar medium aerobic incubation.

Detection of specific and non-specific microorganisms:

The standard contains guidelines for the detection and identification of specified microorganisms in cosmetic products as well as for the detection and identification of other kinds of aerobic mesophilic non-specified microorganisms in cosmetic products. 

The standard contains guidelines for the detection of Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus or Candida albicans. 

The detection is carried out by enrichment in a nonselective

broth followed by isolation and identification. The identification consists of gram staining, catalase- and oxidase test followed by the use of an identification test kit.

ISO method for detection of specific microorganisms:

In all four standards, the first step is enrichment in a non-selective broth to

increase the number of microorganisms without the risk of inhibition by the

selective ingredients present in the growth media. The second step is isolation on selective media followed by identification tests.

ISO 16212 Counting of yeast and mold

The method includes colony count on Sabouraud dextrose-chloramphenicol agar.

Efficacy of preservation

A challenge test is a procedure in which a product is challenged by exposure to specified types of bacteria and fungi. Then place the product in at a given temperature, samples are collected at specified time intervals, and numbers microbiological determination. Typically, the product is in a challenged state of microorganisms Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans. The antimicrobial performance of the product is acceptable if the antimicrobial performance of the product is significant when a decrease or no increase in the number of viable microorganisms is observed products are tested considering storage and use. Challenge testing should be performed during development to preserve the system and as an evaluation of the effectiveness of the complete conservation, of cosmetics that are in use or about to end.