Who has never thrown away a cosmetic product, maybe still half full because they were unsure about the expiration date? Who has never wondered if an expired product could irritate the facial skin? Well, today we analyze the expiration of cosmetics and the PAO, because knowing these details helps save money, time, and your skin.
Knowing the duration of your cosmetics allows you to plan purchases wisely, and that is why in this article we will try to be as specific as possible, delving deeply into the meaning of PAO, covering the risks of an expired cosmetic, and finally the tips to better preserve products to avoid unnecessary waste.
What is PAO in cosmetics
Specifically, PAO stands for Period After Opening and indicates the period during which a face cream, or a cosmetic in general, remains safe and effective after the packaging has been opened.
By law, you will find this symbol on a package, especially on products that last more than 30 months from production. But how do you recognize the PAO on a cosmetic? You just need to look for the symbol of an open jar with numbers like 6M, 12M, 24M, which tells you exactly how many months you have to use that cosmetic product once opened.
This is because once opened, a cosmetic comes into contact with:
- Oxygen;
- Humidity;
- Bacteria and fingers.
All this promotes microbial growth and oxidation of actives such as vitamin C or retinol, for example. The texture separates, the scents change, and the effectiveness tends to become milder.
How do companies determine the PAO?
Every cosmetic product must be designed to provide reliability and effectiveness over time, for a set and defined period, so its formula must remain stable. The duration of the PAO is therefore established based on specific tests that must consider the effectiveness of preservatives, the formulation, the packaging, and the stability of the actives.
That is why every cosmetic has its own precise PAO determined by its formula, the presence of water, the sensitivity of the actives, and the risk of bacterial contamination.
The PAO symbols: how to interpret them
The drawing on the package, as we have seen, is not decorative but specifically indicates how many months you have to use a well-preserved cosmetic product. This information allows you to understand how to use the product effectively, without the formula being altered in any way; it is your personal guide.
Shall we give some examples? A product with a PAO of 24M provides two years of use after opening and declares that, if well preserved, that cosmetic will have the same effectiveness as if it were just opened.
A simple and quick trick to avoid losing money by forgetting when the product was opened? Remember to mark the opening date on the bottom with a permanent marker.
PAO and expiration date: why they are two different things
You should not confuse the PAO with the expiration date of a cosmetic product. The latter applies to perishable products even if unopened. The PAO, instead, starts from the moment the package is opened. If a product has both, that is, its PAO and expiration date, the expiration date limits everything. Otherwise, for most cosmetic products, the PAO sets the rules.
The rules of cosmetics are clear and require transparent and clear labels to protect all types of consumers. Thus, if a product has a shelf-life of less than 30 months from production, it must show a precise expiration date; beyond this threshold, the PAO is sufficient. In this case, manufacturers guarantee safety and effectiveness up to that limit, but exceeding it is at your own risk: the responsibility lies with the consumer, who must follow storage instructions.
How to properly store a cosmetic during the PAO?
Proper storage of the cosmetic product ensures that it can reach the end of the indicated usage period in perfect condition and effectiveness. In this way, benefits are maximized, waste is reduced, and it also does a favor to the planet as well as to your wallet.
Considering that the main enemies of cosmetics are direct sunlight and humidity, ideally cosmetics should be kept in cool, dry, and dark places, such as a drawer in a bedroom or a well-closed makeup bag. It is essential to avoid placing cosmetics near a heat source, such as a radiator, in a humid place like the bathroom, or in the refrigerator, except when recommended.
Another tip, even if obvious: respecting the PAO of a product also means not opening it if you do not intend to use it! This means it is useless to open a cosmetic product just to try the scent or texture, as degradation processes start immediately.
In short: cosmetics must be stored in cool, dry environments away from heat sources or direct light because heat and sunlight accelerate the oxidation of active ingredients, reducing their effectiveness and safety. For those who want to always have efficient products at home, it is necessary to resist the “temptation to test” a product and open a cosmeceutical only when you really intend to use it.
How to avoid contamination during the period after opening cosmetics
To avoid any contamination and ensure that the PAO is a true indicator of a cosmetic product’s effectiveness, it is always advisable not to put fingers into jars; sterile spatulas are better. Brushes and spatulas should also be washed often; this way, skincare or anti-aging treatments remain effective and useful over time. It is also recommended to always close products tightly.
What signs indicate that a cosmetic is expired or has deteriorated?
Beyond the PAO and expiration dates, you need to know how to identify when a cosmeceutical product has deteriorated. There are many signs, but what can be said is that you should trust your nose and eyes: when the color changes or the cream separates into oily and watery phases, it is a sign of product deterioration; it is the same if the smell no longer seems the same or if the notes you used to smell disappear.
Among other warning signs that the product was not well preserved and did not survive its PAO are a lumpy texture or possible discomfort upon contact.
What are the risks of using a cosmetic product after the PAO expiration?
It is really important to respect the PAO; there are risks especially for those with sensitive skin. As we have seen, when a cosmetic is opened, contact with air and external agents alters and deteriorates the entire stability of the formula, allowing the formation of bacteria and small microorganisms that can lead to adverse reactions such as:
- Bumps;
- Pimples;
- Skin irritations.
Therefore, for those with reactive skin – and even for those without particular sensitivities – it is always important to respect the expiration indications on the product.
The period after opening and the expiration date are essential indications to protect the skin but also to avoid waste. The PAO shows the months during which a product remains safe and effective after opening; the expiration date indicates when a product, regardless of its opening, ceases to be effective. All these rules are important because using a cosmetic product beyond the usage terms can cause irritations, pimples, bumps, or allergies, especially on sensitive skin.
