Each cosmetic product marketed requires a challenge test (CT), regulated by the European Regulation 1223/2009. According to this regulation, CT is not required for two categories: low microbiological risk products (e.g. product with alcohol above 20%, products with organic solvents, high/low-pH product), and single use or no air contact products.1
Standard ISO 2962: 2010 sets limits of pH (below 3 or above 10), ethanol (above 20%) and aw (below 0.75), that defines a product as low risk of microbial contamination and such that does not require the application of microbiological International Standards for cosmetics.2
Challenge test is an effective solution to evaluate contamination risks, and avoid bacteria, mold, or yeast proliferation. However, CT is expensive and laborious. Without an effective preservative system, proliferation of microorganisms can cause health hazards, skin infections, pH changes and degradations (odour, colour, general appearance).3
Many publications have studied parameters which influence CT. In the food industry, an article in 2008 by Bekada AMA et al.,4 studied water activity, pH and temperature on the growth rate of mucor racemosus isolated from soft camembert cheese. In the cosmetic industry, a work conducted by Rahali Y et al.,5 studied the optimisation of preservatives in a topical formulation using experimental design.6
Log in or register FREE to read the rest
This story is Premium Content and is only available to registered users. Please log in at the top of the page to view the full text.
If you don't already have an account, please register with us completely free of charge.
