What is Period After Opening (PAO) ?
This is a symbol that represents how long does the product remains stable without causing harm to consumers after opening the product for the first time. Do not confuse PAO with expiry dates as expiry dates shows the shelf life of a product in its unopened state if it is stored under the recommended storage condition in its original packaging.
How to decipher PAO?
M literally means months therefore if it is written as 12 M it means the product is recommended to be used within 12 months after opening. This symbol is commonly seen on cosmetic products but I have noticed that products like sheet masks does not have such symbols because you just dispose after each usage, for such products it is important to look at its expiry dates.
Why is it important for companies to include PAO?
Besides being tightly regulated especially in Europe, here are the few reasons why:
- To ensure the product maintains its quality and specifications
- To determine if an expiry date or PAO is required for the product
- To ensure the safety of consumers by ensuring it passes the microbial stability tests
- To take care of the image and reputation of companies.
What parameters are considered?
Products are generally evaluated based on the changes in colour, odour, appearance, pH, viscosity, density, weight and microbiology. Of course, each parameters differs with different products. To simplify, any changes of parameters indicates a modification of its quality and therefore affects the product effectiveness and possibly the safety of usage.
Why is PAO especially important for us consumers?
While certain products (eg. Hand creams) will not cause any serious harm to us after using past the recommended PAO, it is not the same for most skincare products. Following the PAO is particularly important for:
- Products that can be easily contaminated and spread infections
In my opinion these are products that comes in a tub (mostly creams and cleansing balms), though most products come with a separate spatula it is still never as hygienic as products that comes in a squeezed tube or pump. You know once a product is contaminated, the bacteria will just keep multiplying. Imagine slathering bacteria on you skin!
- Products with little to no antibacterial agents or preservatives
These are usually organic and natural products. Most of them are of single usage or an oil based products. There are always discussion regarding whether having preservatives in skincare products are good or bad but that’s like a whole new topic which I might touch in the future. Just know that it is a fact that products that contains water needs preservatives and even with preservatives, their effectiveness wears off in time. Without preservatives, you will be slathering all the bacteria on your skin again. No!
- Products with active ingredients
These are usually your serums and essences where they are packed with potent active ingredients that are targeted for certain skin conditions. Great examples are products with vitamin A (retinol) and vitamin C. I used to keep my most expensive products and ‘save’ it only for special occasions but often it goes out of date. What a waste! Now I use generous amount of the serums ones its opened to not miss its prime time.
- Products we rely heavily on its effectiveness
A really good example would be sunscreens. Using after it have gone past its PAO would be absolutely pointless as it will not protect your skin as well or at all from the harmful UVAs and UVBs. Most sunscreens remain effective for 12 months and adequate usage should make it last for more than 6 months anyway.
How to remind yourself about PAO?
I love it when products include a section where you can input the date where you open the product – not on the packaging itself but on the bottle or tub because I usually just toss the product packaging after first usage. This is great as it makes the consumer to be more aware about the expiry of the product and to use it within the highest efficacy period.
Unfortunately, not all products have that and it is up to us as a consumer to remind ourselves. Suggestions :
· Use permanent marker to note down the date of opening.
· Use label stickers to note the date of opening and stick on the product.
Anyhow you will find a way to remember!
Should I really dispose my products after it have passed its PAO?
Yes and no? Based on all the information that I have gathered, I do think it is best to not use the product after the PAO considering its reduced quality, efficacy and hygiene concerns. However, I still feel it is such a waste to just throw them away. Instead of throwing them away I try to use them for other purposes. For example, I use face creams that have gone passed its PAO as a neck cream, body lotion and hand cream – basically anywhere except for my face. Obviously if the product starts to smell bad and looks different just bin it!
Another mindset shift that I have recently adopted is to not ‘save’ the best for the last especially for products with actives like serums and essences because ones opened the product looses their effectiveness gradually with time. The best way would be to think the fresher the skincare product the better and more effective it is !
Cheers to better skin days