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What should we know about the Period after Opening (PaO) and the Date of Minimum Durability (DMD)?

As far as consumer information is concerned, the durability of use of cosmetic products is one of the requirements that must be included on the product labelling, in a precise and easily understandable way, so that the consumer is aware of the date until which the product, stored under appropriate conditions, continues to fulfil its initial function and remains safe, i.e., the date by which it is best to use the product, known as Date of Minimum Durability (DMD). The date itself or details of where it appears on the packaging shall be preceded by the following symbol or the words “best used before the end of”:

DMD Cosmedesk

The DMD shall be clearly expressed and shall consist of either the month and year or the day, month, and year, in this order. Whenever necessary, it should also be accompanied by an indication of the conditions that must be satisfied to guarantee the stated durability.

Indication of the DMD is not mandatory for cosmetic products with a minimum durability of more than 30 months. For such products, the consumer should be informed of the Period after Opening (PaO) for which the product is safe and can be used without any harm, except where the concept of durability after opening is not relevant, as in the case of single-use products, products not at risk of deterioration or products which do not open.

The PaO shall be indicated by the following symbol followed by the period (in months and/or years):

PAO Cosmedesk

Initially, the PaO may be estimated theoretically according to the “Recommandations relatives a l'estimation de la période après ouverture (PAO)”, published by the Agence Française de Sécurité Sanitaire des Produits de Santé. This estimation takes into account five factors (intrinsic resistance of the formulation to microbial contamination, interface product/environment related to the use (type of packaging), duration of foreseeable use (adequacy of volume/dose/frequency), area of application and target population), rated from 1 to 4, respectively from lowest risk (1 to 2) to the most important (3 to 4), to calculate the theoretical risk (TR) which estimates the theoretical PaO.

What we offer

With Cosmedesk you can manage your product's stability data, namely indicate the established DMD and PaO, benefiting from the automatic generation of template sentences with this information that can be included in the Cosmetic Product Safety Report (CPSR). When the PaO is not relevant, it is also possible to define the type of product under assessment which justifies the non-indication of the PaO.

Cosmedesk also includes the option to estimate the PaO according to the French Agency guidelines and generates a document with this data.



Regulation (EC) No 1223/2009 of the European Parliament and of the Council of 30 November 2009 on cosmetic products

Cosmetics Europe: Guidelines on cosmetic product labelling, 2011

Agence Française de Sécurité Sanitaire des Produits de Santé. Recommandations relatives a l’estimation de la periode apres ouverture (PaO). 2006

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