You know the image of a open jar on your favorite cream or cleanser? Inside there are usually written gods numbers. But what are they and what are they for? It’s about the PAO, Period After Openingi.e. the maximum period after opening in which the product is still safe to use. In fact, when they are still sealed, many cosmetics have excellent durability, but when they let’s open come into contact with the external environment, with our hands often full of germs and can degrade, become contaminated or lose effectiveness. This is why the PAO is inserted instead of the expiry date: to define it, companies must carry out various tests considering the stability of the preservatives, the type and normal conditions of use of the product and a series of other variables.
Which cosmetic products have the PAO graphic symbol
Premise: not all cosmetics have excellent durability. To understand something we need to turn to Regulation (EC) 1223/2009the European regulatory bible for cosmetics, which establishes common rules for the whole EU regarding composition, safety, labelling, notifications, bans on dangerous substancessafety assessment obligations, and so on. The Regulation generally requires the indication of minimum shelf life date on cosmetics: that is, the date by which it would be best to use your cream (still unopened), assuming you have it stored in appropriate conditions.
However, if this date exceeds 30 monthsthen it is no longer necessary, but consumers must be informed about what happens once the cream or aftershave is opened! That’s where the PAO comes in, that is the period after opening in which the product remains safe and does not represent a risk to our health.
It is often represented with a open jar with a number and an M written inside or next to it (for example, “6M” or “12M”) to indicate the maximum number of months in which you can use the product without risk. Now the question is: do you remember how long ago you opened the sunscreen, the aftershave or that brand new lipstick with an iridescent color that then ended up forgotten? Maybe it’s time to go check it out.
What happens to an opened cosmetic
The ironic answer: life. Wanting to be precise and scientifically correct, once opened, our cosmetic comes into contact with the external environment and undergoes various degradation processes. The oxygen present in the air can induce oxidation processes, breaking down the molecules present in the product, any fats can go rancid and a whole series of chemical-physical degradations can occur which, in the best of cases reduce effectiveness of your favorite cream. At worst, can cause irritation and damage to the skin.
Furthermore, it can be contaminated by microorganisms which affect their quality and safety, in particular for those jarred products in which we have to “dip” our finger every time to pick them up and apply them (in fact, sometimes you can find special spatulas for the application, which however we then leave outside exposed to the environment, so the problem persists).
How is the Period After Opening calculated?
There are no univocal indications, but companies are required to follow not only the European directive, but also the indications of the Scientific Committee on Consumer Safety (SCCS).
First of all, manufacturers must subject the cosmetic to various tests microbiological, safety and stability tests of the intact package to evaluate the minimum shelf life. If, as we said, it exceeds 30 months, then the real challenge begins for our cream, because producers have to see if it remains stable. even under conditions in which a normal person would use it!
It is subjected to challenge testthat is, it is specially loaded with bacteria to see if the preservative system holds up. Then it is stressed to different environmental conditions: exposure to light, temperatures, humidity. Evaluating is fundamental where the product is appliedhow many times a day, where is it potentially stored by the consumer (in the bathroom or bedroom? Does he keep it in his bag or does he leave it in the car?), who uses it (a single person or the whole family, and therefore there is potentially a greater risk of contamination?).
When the PAO is not mandatory
Some products are exempt not only from the minimum shelf life, but also from the PAO. They are for example i products in pressurized containers. Think about aerosol deodorants, which physically cannot be opened and they never come into contact with the external environmenttherefore they are not at risk of being degraded.
Another product category that does not require PAO is produce disposablesuch as samples or vials. In these cases, since the product must be opened and used immediately, it makes no sense to enter an “expiry” date after opening.
