Shelf Life – Cosmetic Product Stability and Expiration

What Is Shelf Life?

Shelf life is the period during which a cosmetic or personal care product is expected to remain suitable for use. The manufacturer is responsible for determining an appropriate shelf life as part of demonstrating the product's safety and quality.

Shelf life depends on factors such as the formulation, packaging, storage conditions, and stability of the ingredients.

Shelf Life and Cosmetic Labelling in Europe

Under European cosmetic legislation, products with a minimum durability of more than 30 months generally do not require a best-before date. Instead, they must indicate the Period After Opening (PAO) where applicable.

The PAO specifies how long the product is considered suitable for use after it has first been opened. It is expressed in months and is normally represented by the open-jar symbol, for example 12M for 12 months.

For products with a durability of 30 months or less, a date of minimum durability must be indicated. This is commonly accompanied by the hourglass symbol or an appropriate "best used before the end of" indication.

Period After Opening (PAO)

PAO relates specifically to the period following the first opening of the product. Once opened, the formulation can be exposed to air, microorganisms, moisture, and repeated consumer handling.

Packaging can therefore have an important influence on the appropriate PAO. Airless packaging, pumps, tubes, and other protective systems may provide different conditions from wide-mouth jars.

Factors Affecting Shelf Life

A cosmetic product can deteriorate before its expected shelf life if it is exposed to unsuitable conditions. Important factors include:

• High temperatures
• Direct sunlight
• Repeated exposure to air
• Microbial contamination
• Packaging interactions
• Oxidation
• Changes in colour, odour, texture, or viscosity

For this reason, products should be stored according to the manufacturer's instructions and protected from unnecessary exposure to heat and sunlight.

Determining Shelf Life

Shelf life is normally established using stability testing and consideration of the product's formulation, packaging, microbiological quality, and intended storage conditions. The results help determine whether the product maintains its required physical, chemical, and microbiological characteristics throughout its expected life.

Some products may be less susceptible to deterioration because of their formulation or packaging. Examples include certain aerosols, high-alcohol perfumes, and single-use products.

Source: https://www.cosmeticsinfo.org/