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Check for a Period After Opening (PAO) symbol -

Some products have a symbol that informs you of when you should toss them after opening them. For the cases where you don't see this, read on.

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Moisturizer: one year -

Moisturizers that use natural ingredients in place of artificial preservatives won't protect themselves from bacterial contamination as well as synthetic alternatives do, and will go bad much sooner.

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Toner: six months to a year -

As a water-based product, the shelf-life is short, but a toner's added ingredients can help increase its best-by date. Give it a smell, and keep an eye on the color and consistency to avoid skin irritation.

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Micellar water: six months maximum -

This multitasking facial wash, makeup remover, and moisturizer has one of the shortest expiry dates, as water encourages bacteria growth.

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Concealer: one year -

Concealers use oils and hydrating agents to give that smooth cover-up, which also means a shorter shelf-life. If it's looking dry, lumpy, or discolored, throw it out, or it'll only make skin blemishes worse.

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Powder foundation: up to two years -

The dry texture makes it harder for bacteria to grow, but you should still use clean makeup tools, wash your hands before use, and occasionally clean the top layer to increase its shelf-life.

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Liquid/cream foundation: six months to one year -

The liquid and cream versions of foundations contain more water, oils, and hydrating agents, so they have a shorter shelf-life and an increased risk of bacterial contamination.

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Can’t remember when you bought your foundation? -

A telltale sign of expiration is when the oils rise to the top and the consistency thickens. If your foundation creates a streaky finish, toss it.

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Protect your foundations and concealers -

Prevent the liquid from separating by keeping it somewhere cool and regularly shaking it. You should also keep your application tools clean and avoid touching the liquid to stop the spread of bacteria.

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Cleanser: one year -

Most cleansers should last about a year in a cool place, but keep an eye out for lumps, discoloration, and warped packaging.

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Powder blush: two years -

Bacterial contamination and discoloration is minimized if the blush is never left exposed to air, which means you should definitely throw away powders with broken or missing lids.

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Protect your blushes and bronzers -

Avoid using a greasy concealer before you apply, and make sure your brush is always clean before each use to limit the amount of oil that gets transferred to the powder.

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Lipstick: one to two years -

The one at the bottom of your makeup drawer, or the one you found while cleaning your car: they're chalky and have a distinct odor, and you must sadly throw them out.

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Protect your lipstick -

Never leave lipstick without a lid, and use a lip brush when you can to prevent extra contact. You can also remove the top layer of bacteria growth on them with makeup wipes to increase their shelf-life.

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Protect your lipstick -

You can keep lipsticks in the fridge, as the cold slows the breakdown of ingredients. Also, try not to apply lipstick right after eating, as this cultivates bacteria.

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Lip liner: one year -

Sharpen them frequently, keep a firm cap on them, and you can enjoy these wonders for up to a year.

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Brow pencil: two years -

Brow pencils keep for a long time if you sharpen them (removing any bacterial growth on the top layer), and if you keep a lid on them.

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Mascara: around four months -

Many experts say it's actually three months with everyday use and six months with occasional use. The short life of mascara is due to the bacteria and germs that are constantly transferred from our eyes to the wand/tube and back.

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Protect your mascara -

Stop pumping your mascara! Forcing air into the tube dries out the product and encourages bacterial contamination. Instead, rotate the wand in a circular motion while in the tube. Also, never add water to dry mascara: just toss it! 

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Eye shadow: six months to two years -

The cream shadows will only last six months because of the hydrating agents. Powders can last up to two years, but watch out for discoloration, waxy build up, or a strange odor.

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Liquid/gel eyeliner: four to six months -

Liquid and gel eyeliners gather bacteria faster, and you should definitely throw them out if you've had an eye infection, or if they smell or look strange.

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Pencil eyeliner: one to two years -

Pencil eyeliners, if cared for properly, can last up to two years.

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Protect your eyeliner -

Clean the tip of liquid eyeliners after each use. With the pencil, regularly sanitize your sharpener with cotton and rubbing alcohol, then use that sharpener regularly.

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Lip balm: one year -

Careful to have clean hands before using lip balm in a pot or jar, or just opt for lip balm tubes, which tend to last longer.

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Lip gloss: one year -

Watch out for changes in texture and thickness, and never, ever pump your lip gloss again.

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Fragrances: eight to 10 years -

Fragrances stored away from heat and bright light can last for many years. You'll probably smell when it goes off, but it may also change color.

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Nail polish: two years -

After opening, nail polish ingredients can evaporate, causing it to thicken and separate. Look out for changes in color, thickness, and texture.

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Makeup brushes: clean them! -

Brushes can last a long time if you take care of them. Wash them once a month with warm water, mild soap, and a dash of olive oil (to break down the oil in makeup), then rinse thoroughly.

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When to replace your brushes -

It's time to throw them out when the bristles start falling out. 

See also: Bizarre ingredients found in beauty products

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