Just like food, cosmetic products can expire too and when they do, they become ineffective and possibly harbor bacteria that will cause infection. A study published in the International Journal of Cosmetic Science evaluated the makeup routines and habits of 44 women, 70% of these women used some type of expired product—mostly eye makeup (mascara, eyeliner, eye shadow). The researchers sampled their eye makeup for contamination, and found that 67% contained potentially harmful levels of microorganisms (including Staphylococcus Corynebacterium and Moraxella, all common in bacterial skin infections).
All cosmetic products have a shelf life. The shelf life of cosmetics is important because even an effective preservative system will lose efficacy after a certain amount of time and at that point the product can become contaminated with bacteria and molds. Also, many active ingredients are surprisingly fragile; it’s only a matter of time until oxygen and heat render them useless. In the US, there is no requirement for cosmetics manufacturers to put this information on their products. The European Union has a system called “period after opening”.
Period After Opening (PAO)
The PAO symbol is simply an open jar with a number followed by the letter M, which indicates for how many months the product will last once it has been opened. So “12M” means you should throw the product away 12 months after opening it. Products that last 30 months or slightly less, instead, are only required to display a “best before” date.
Manufacturers determine the appropriate shelf life based on the shelf life of the raw materials and internal stability testing. It is important to note that expiration dates are simply “rules of thumb,” and that a product’s safety may expire long before the expiration date if the product has not been properly stored. Manufactures don’t take into consideration how the product is stored and used by the consumers. If a product has been exposed to heat, light or bacteria for instance, it will lose its effectiveness and go bad sooner.
Sharing makeup increases the risk of contamination. “Testers” commonly found at department store cosmetic counters are even more likely to become contaminated than the same products in an individual’s home. If you feel you must test a cosmetic before purchasing it, apply it with a new, unused applicator, such as a fresh cotton swab.
A Guide To Skincare Product Expiration Dates
As mentioned above, how long a skincare product lasts also depends on how it is stored and used, so the following expiration dates should be taken as general guides rather than exact indications:
- Mascara, liquid or gel eyeliners: 4 to 6 months (always throw away dry/clumpy mascara—never add water or saliva to moisten it)
- Cream, Liquid or Stick Foundations or Concealers: 6 months to 1 year
- Powder-based products: 2-3 years
- Lipsticks, Lip Gloss, & Lip Pencils: 2-3 years
- Cleansers: 1 year
- Toners: 6 months to 1 year
- BHA or AHA Exfoliants: 1 year
- Creams and Serums with Antioxidants and Retinoids: 9 months (these ingredients can oxidize when exposed to light and air and lose effectiveness)
- Facial or Body Moisturizers: up to 18 months
- Sample Packets: 1 day
- Deodorant, Anti Perspirant, Soap: 3 years
- Sunscreen: 1 year
Products that contain water as one of the first ingredients have the shortest shelf life after opening because water encourages the growth of bacteria and other microbes. Also susceptible to bacterial contamination and breakdown from exposure to air are products that that contain plant extracts. Products made up of almost no water (such as powders) last the longest, because almost nothing can grow in these kinds of products. If your product is labeled “preservative-free” you should take extra caution, because without some kind of preservative system bacteria can flourish easily.
Dos and Don’ts of Cosmetic Care
Here are a few tips on how to prolong the shelf life of your products.
- Always read the instructions carefully and take note of any warnings for use.
- Wash your hands before applying makeup (especially if you need to dip your fingers into the container.
- Tightly close containers and jars after use.
- Throw away products that become discolored, runny or lumpy, have separated or develop a strange odor.
- Throw away products when the product labeling indicates.
- Replace applicators frequently or use disposable makeup applicators.
- Store cosmetics in a clean, dry place and not in extreme environments.
- Share your cosmetic products with others
- Use water of saliva to moisten cosmetics or applicators as this might add bacteria or other germs.
- Add water to dilute cosmetics unless directed by the manufacturer. This may make the preservative system ineffective.
- Use eye makeup if your eyes are irritated or infected. Throw out cosmetics that were used during a period of eye infection.
- Store products in the refrigerator. Skincare formulas are designed to withstand the average fluctuations in temperature, but not long-term heat or cold storage.
- Store products in direct sunlight.
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