Cosmetics Preservative Efficacy Tests – Challenge tests

Test accredited in our laboratory according to ISO 10725 by ENAC (Spanish National Accreditation Entity). 

Test with the Certificate of Good Laboratory Practices (GLPs)

Assessment of the antimicrobial protection of a cosmetic product - Challenge test of preservatives. Standard UNE-EN ISO 11930: 2012 (formerly NF T75 611 standard). Exposure tests are intended to determine the power of a preservative to prevent bacterial or fungal contamination during its use, so they are mandatory tests for those products that may pose a risk of infection for the user or a deterioration of the product. To perform the exposure test ("Challenge"), an artificial contamination of the sample is carried out with 5 microorganisms, at a concentration established by the standard. The microorganisms used in the efficacy tests are Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Candida albicans and Aspergillus brasiliensis. The cosmetic inoculated with those microorganisms are followed up at 0 hours, 7, 14, and 28 days. The inoculated microorganisms must descend throughout the follow-up, and must reach a certain logarithmic reduction, in order to meet established criteria A or B. In the case of Aspergillus brasiliensis, it should not suffer an increase after 28 days.

Assessment of the antimicrobial protection of a cosmetic product - Challenge test of preservatives according to the European Pharmacopoeia. Exposure tests are intended to determine the power of a preservative to prevent bacterial or fungal contamination during its use, so they are mandatory tests for those products that may pose a risk of infection for the user or a deterioration of the product. To perform the exposure test ("Challenge"), an artificial contamination is carried out up to the level established by each standard. The microorganisms used in the efficacy tests are Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans and Aspergillus brasiliensis. The European Pharmacopoeia allows the use of other microorganisms if it is considered that they can represent possible contaminants for the product. To do this, the cosmetic product is inoculated with the mentioned microorganisms, and the follow-up is carried out at 0 hours and at different subsequent intervals of time, which vary according to the type of product, until the final reading at 28 days. The inoculated microorganisms must descend throughout the follow-up, and must reach a certain logarithmic reduction, in order to meet the A or B criteria established in the European Pharmacopoeia for each type of product (topical, oral, ophthalmic use, etc.). Criteria A expresses the maximum recommended efficacy that must be achieved. In justified cases, when criteria A can not be reached, for reasons of an increased risk of adverse reactions, criteria B may be sufficient (satisfactory).

Differences between the preservation efficacy test (Challenge Test) according to UNE-EN ISO 11930 and European Pharmacopoeia                                                                        

UNE-EN ISO 11930

(formerly NF T 75-611)

European Pharmacopoeia

Microorganisms: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans and Aspergillus brasiliensis.

Microorganisms: Staphylococcus aureus, Peudomonas aeruginosa, Candida albicans and Aspergillus brasiliensis. The guideline advises to include Escherichia coli for products of oral use, so IVAMI will include this strain in this type of products. It also indicates that other strains, which may represent contaminants for the preparation, may be included.

Sampling: Always 0 hours for all microorganisms and also 7 days for bacteria and yeast, 14 days and 28 days for bacteria, yeasts and molds.

Sampling: Always 0 hours for all microorganisms and besides, depending on the type of product, the following sampling will be carried out: For topical products 2 days, 7 days, 14 days and 28 days, for bacteria, and at 14 and 28 days for molds and yeasts; For parenteral and ophthalmic products at 6 hours, 24 hours, 7 days, 14 days and 28 days, for bacteria, and 7 days, 14 days and 28 days for molds and yeasts; For oral products 14 days and 28 days for bacteria, molds and yeasts.

Inoculum: bacteria: 105 /CFU/mL; yeasts: 104 CFU/mL and molds: 103 UFC/mL.

Inoculum: 105 to 106 CFU/mL for all microorganisms.

Assessment criteria: Criteria A considers that the product is protected against microbial proliferation that may present a potential risk to the user. Criteria B considers that the product is protected if the risk analysis demonstrates the existence of control elements not related to the product, indicating that the microbiological risk is acceptable.

Assessment criteria: The acceptance criteria depends on the products uses (parenteral, ophthalmic, oral or topical) - Criteria A, expresses the effectiveness that must be achieved, but criteria B, can be sufficient (satisfactory), when the criteria A cannot be achieved, for reasons such as increased risk of adverse reactions.

 

IVAMI´s comment: The UNE-EN ISO 11930 standard, considers all products, whatever their use, equal with the level of protection they must offer and the European pharmacopoeia establishes interpretation criteria according to the use of the product, so which for some preparations would be less restrictive, and for others prepared more restrictive. From this point of view, the European standard is more restrictive. 

Submission form with product characteristics and variables for tests

In case of requesting the realization of the tests, you must send us with the product the corresponding completed submission form in which the characteristics of the product and the variables, if appropriate, will be indicated.

Sample volume

The volume of product required is 250 mL.

Deadline for delivery of results

The report will be available in approximately 35 to 40 days from the reception in our laboratory of the product for testing and the submission form with selected conditions. If we have before the results we would communicate it.

Cost of the test (according to any of the standards guidelines, UNE-EN ISO 11930 or European Pharmacopoeia, including the microorganisms and the timing evaluations recommended by those guidelines): Consul to: ivami@ivami.com.

Cost of the test (according to any of the standards guidelines, UNE-EN ISO 11930 or European Pharmacopoeia, including the microorganisms and the timing evaluations recommended by those guidelines, plus any other microorganism chosen by the customer, ex. gEscherichia coli, Burkholderia cepacia, Zygoccharomyces rouxii, etc.): Consult to ivami@ivami.com.