Safe Cosmetic Products and the Importance of Analysis

Cosmetic Products Safety Assessment Guide" emphasises that cosmetic products must be safe for human health. In terms of product safety in cosmetics, the main tests to be performed are physical/chemical analyses, microbiological analyses, and challenge test (preservative efficacy test).

Physical Analyses

The main physical properties mentioned in the Safety Assessment Guide are colour, odour, appearance, pH, density and viscosity. All these properties provide information about the general structure and appearance of the product and show whether there are any issues with the product in terms of general appearance.

Chemical Analyses (Heavy Metals, Paraben, SLS/SLES)

Heavy Metals: Another group of analyses that has gained importance in terms of product safety is chemical analyses. Heavy metals pose the greatest risk in cosmetics in this respect. The Guide on Heavy Metal Impurities in Cosmetic Products defines which heavy metals should not be present in cosmetic products and their limits. According to this guide, the heavy metals that should be prioritised in order to prevent adverse health effects in cosmetic products are lead, arsenic, cadmium, mercury and antimony.

Limit values for heavy metals in cosmetic products are as follows:

• Lead 20 ppm, • Arsenic 5 ppm, • Cadmium 5 ppm, • Mercury 1 ppm, • Antimony 10 ppm.

Acceptable limit values for toothpastes are lower:

• Lead 1 ppm, • Arsenic 0.5 ppm, • Cadmium 0.1 ppm, • Mercury 0.2 ppm, • Antimony 0.5 ppm Dyes used in cosmetics in particular can lead to heavy metal contamination. In addition, raw materials used can also create a heavy metal risk. In the event of long-term exposure to heavy metals mentioned in the regulation, heavy metals can cause many diseases, with cancer being the most significant. Heavy metal analyses are of great importance for product safety. Saniter Laboratory holds TÜRKAK accreditation for heavy metal analyses in all cosmetic products. Paraben: A preservative chemical substance used in the pharmaceutical and cosmetic industry. It is frequently used especially for its bactericidal and fungicidal activity. Paraben is used as a preservative in all cosmetics, including shampoos, hair creams, makeup products and sunscreens, because it extends the shelf life of the product and increases its heat resistance. As a result of research conducted on women with breast cancer, paraben was found to be present in tumour samples obtained. However, a direct link with breast cancer has not yet been clearly proven. Limit values for parabens are given in Annex V of the Cosmetic Regulation, which lists preservatives permitted for use in cosmetic products. However, the regulation states that "it should not be used in products that are not rinsed off and are prepared for application to the nappy area of children under 3 years of age". For this reason, paraben should not be used in baby products for ages 0-3 (especially in wet wipes). SLES/SLS Analysis: Sodium laureth sulphate (sodium lauryl sulphate), SLS, is the sodium salt of lauryl sulphate. It is used in shampoos, toothpastes, shower gels, liquid soaps, foam baths, laundry and dishwashing detergents, and makeup products. SLES shows similar properties to SLS as sodium lauryl ether sulphate. It is used in cosmetic cleansing products such as shampoo, soap, shower gel and bath foam to reduce surface tension. It is preferred for this process because it is easily thinned with salts and has a good foam-forming character. Its relatively low cost is another reason for preference. SLS and SLES are irritant substances. Especially in the event of excessive contact, they can cause skin irritation and irritancy. The main danger for SLS and SLES is the possibility of contamination with 1,4-dioxane. 1,4-dioxane, identified by the EPA as a possible carcinogen in humans, can become contaminated during the production process, in the ethoxylation step. For this reason, SLS and SLES-free cosmetic products are being produced and are in demand by consumers. To prove this claim, these analyses need to be performed.

Microbiological Analyses

According to the Guide on Microbiological Control of Cosmetic Products issued by the Turkish Medicines and Medical Devices Agency, microbiological analyses to be performed on cosmetic products have been determined. Microbiological risk analysis includes factors such as user type, application area, possible changes in cosmetic products and the ability of microorganisms to cause disease. Microorganisms that must not be present in cosmetic products are Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans and Escherichia coli. These microorganisms must not be present in cosmetic products because they cause skin infections and are pathogenic.

Challenge Test

The microbial load of cosmetic products must remain within limits throughout their shelf life. For this purpose, the antimicrobial activity of the preservatives used must be maintained throughout the product's use and shelf life. The test performed to determine the preservative efficacy in any product or to investigate various substances as preservatives is called a challenge test/screening-stress test/preservative efficacy test. Preservative efficacy analysis is used to evaluate the protection of a cosmetic formulation against microbial contamination. The preservative efficacy test is performed in accordance with ISO 11930 standard. The preservative efficacy test is performed with the following microorganisms: • Pseudomonas aeruginosa ATCC 15442 • Staphylococcus aureus ATCC 6538 • Escherichia coli ATCC 8739 • Candida albicans ATCC 10231 • Aspergillus brasiliensis ATCC 16404 Çağlayan ÇATAL / Technical Director / Saniter Laboratory