Distinguish Date of Minimum Durability (DMD) and Period After Opening (PAO)

The concepts of Date of Minimum Durability (DMD) and Period After Opening (PAO), despite being very simple, are of essential importance.

The DMD is the date until which the cosmetic product, stored under appropriate conditions, will continue to fulfill its initial function and remain safe for the consumer.

This date corresponds to the shelf life of the product, that is, the recommended time period that a cosmetic product can be kept after its production, during which the defined quality of the product remains acceptable under expected conditions of distribution, storage, display and usage, and it’s usually extrapolated from the Stability Study of the cosmetic product.

The DMD shall be clearly expressed on the label of the cosmetic product and shall consist of either the month and year or the day, month and year, in that order. If necessary, this information shall be supplemented by an indication of the conditions that must be satisfied to guarantee the stated durability.

The date itself or details of where it appears on the packaging shall be preceded by the symbol below or the words: ‘best used before the end of’.

However, if the cosmetic product has a minimum durability of more than 30 months, indication of DMD is not mandatory. Under these circumstances, it should be indicated the PAO which is the period of time after opening for which the product is safe and can be used without any harm to the consumer.

This period can be theoretically estimated taking into account the following factors (not exclusively): intrinsic resistance of the formulation to microbial contamination, product/environment interface related to use, foreseeable duration of use, application area and target population.

In the event of, the PAO shall be indicated on the label of the cosmetic product by the symbol beneath followed by the period (in months and/or years).

Both DMD and PAO should be confirmed by a real-life stability study.

Do you have any questions regarding DMD and PAO of your cosmetic product? Contact us and talk with an expert!