All the cosmetics are under the risk of microorganism contamination. Aqueous cosmetics products provide the ideal environment for the reproduction of the fungi and bacteria as long as they do not have proper protection. Powder cosmetics (eye shadows, face powders and the others) might be exposed to contamination in time. There might be undesirable changes in the smell, color, viscosity and performances of the cosmetics products as a result of the microorganism contamination. The reason for those changes are the degradation which the microorganisms make on the product ingredients and the metabolites in the product due to the microorganisms. The microorganisms in the contaminated cosmetics product might infect the disintegrated skin. Endotoxins and the other metabolites produced by the Gram-negative bacteria and the other bacteria might also cause corrosion, irritation and allergy in the skin.

Test Methods Used in the Protective Effectiveness

The protective effectiveness tests are the tests made to find the minimum protector quantity needed to protect the contamination of the preparation in cosmetics and pharmaceutical products.
Those tests are done in accordance with the regulations of,
English Pharmacopeia (EP),
United States Pharmacopeia (USP),
Cosmetic, Toiletry and Fragrance Association (CTFA).
Also; There is Linear Regression Method.
Linear Regression Test
As a result of the suspension of the test organism prepared in certain rates with the sample to be analyzed, the plate count (microorganism count) is made in 2, 4 and 24th hours for bacteria and 4, 8 and 24th hours for fungi in the suspension. As long as there are not organisms less than 10 for each ml in the previous aerobic plate count, the next samples are counted in next 3, 5 and 7 days. This method is faster when compared to other methods (USP3, CTFA and so on) in terms of time period. This method is known to provide quantitative and reliable results when applied correctly.
Although there are some differences among the Protective Effectiveness Methods such as bacteria growth temperature, inoculation processes, time needed for the bacteria count and acceptance criteria, there are basic processes included in all of them. The first of this is the choice of the microorganism.
The Microorganisms Used for the Protective Effectiveness, according to groups, are;
Bacteria
Stapylococcus aureus
Pseudomonas aeruginosa
E.coli
Bacillus subtilis
Streptococcus fascalis
Salmonella chlerasuis
Proteus vulgaris
Yeast
Candida albicans
Saccharomyces cerevisiae
Fungi
Aspergillus niger
Aspergillus oryzae
Trichophyton mentagrophytes
Penicillum expansum
Cephalosporium spp
Some tests Analyzed in our Laboratory;
Antimicrobial Activity Analysis
Bactericidal Activity Analysis
Fungicidal Activity Analysis
Staphylococcus aureus
Candida albicans
Escherichia coli
Clostridium species
Salmonella species
Pseudomonas aeruginosa
Candida parapsilosis
Aspergillus spp.
Fusarium spp.
Please contact with our laboratory for the other bacteria.
Cosmetics Products Susceptible to Microorganism Growth
Shaving Cream
Powders
Lip Sticks
Eye Shadows
Mascara
Tooth pastes
Tooth brush
Soaps
Shampoo
Eye liners
Lip liners
Hair gels
Waxes
Brilliantine
Mouth Waters
Cream
Lotions