When is a cosmetics challenge test not needed?
A cosmetics challenge test is not required for certain types of cosmetic products. Microbiologically low-risk products can be exempt from the preservative efficacy test, because, due to the product characteristics, the likelihood of microbiological contamination for such products is very low or even non-existent. The product characteristics that define products as microbiologically low-risk products are described in ISO 29621:2017 and can be divided into characteristics due to the composition of the product, characteristics that are a consequence of the production conditions, packaging or combined factors.
These characteristics are as follows:
Water activity of formulation: products that do not contain water
The pH of the formulation: highly acidic (pH below 3) or highly alkaline (pH above 10) products
Alcohol content: products with more than 20% alcohol concentration
Formulation with raw materials that can create a hostile environment: such as strong oxidizing agents, polar organic solvents, oxidizing dyes, aluminium chlorohydrate and related salts or propellant gases
Production conditions: if containers are filled at more than 65 degrees Celsius
Packaging types: product packaged in pressurized containers, pump dispensers or single-dose units
A combination of the above-mentioned factors
Any lack of challenge test, however, must be duly justified.