BEST IF USED BEFORE...

Cleaning the refrigerator can be an eye-opening experience. That green fuzz growing on -- well, whatever it used to be -- might make a good science project.

That's what you get past the expiration date.

Unfortunately, cosmetics do not carry that same warning. Just as you wouldn't drink milk a month past its expiration date, you may want to think twice about using a tube of lipstick that's been under the car seat for the last year.

Cosmetics are made with preservatives to keep the products relatively free of bacteria. Each time a container of makeup is opened, microorganisms in the air have an opportunity to invade the product. Adequately preserved products kill off enough of the bacteria to keep the product safe.

Makeup used at home is normally applied once or twice a day. This gives the preservatives a chance to kill any bacteria introduced. In order for these preservatives to work, makeup must be used and stored properly. Leaving containers of makeup in direct sunlight can shorten their shelf life because light breaks down the preservatives.

Cosmetics likely to have a shorter shelf life are those labeled "all natural." Products containing plant-derived substances are often conducive to microbial growth. High temperatures also break down the preservatives. Leaving makeup in an automobile -- where temperatures can easily reach over 100 degrees in the summer months -- will shorten the life of the cosmetics.

Sharing cosmetics increases the risk of product contamination.

Trying to "rejuvenate" a product is also dangerous. Adding liquid could introduce bacteria that could easily grow out of control.

"After a while preservatives (even in properly cared for cosmetics) are no longer effective and will allow bacteria to grow," said Dr. Hal Brown, a Cape Girardeau dermatologist.

If a product has lost its original texture, consistency or fragrance, the preservatives have probably broken down and the product should be discarded.

Although the cosmetics industry isn't required to stamp an expiration date on its products, some manufacturers routinely send notices of products nearing the end of their shelf life. Dora Warren, who has been with the Merle Norman store at Cape Girardeau for the past five years, says that the company notifies the store which items to discard.

Testing cosmetics in stores is a common practice. However, care must be taken to ensure that bacteria is not spread. Many manufacturers supply their retailers with samples of cosmetics intended for one-time use. These "bubbles" assure the consumer that the cosmetic hasn't been previously used. If these one-time use containers are not available, it is important to use a fresh applicator such as a cotton swab.

One of the areas of greatest concern is the eyes. Mascara is considered to have the shortest shelf life. Most companies suggest replacement every two to three months. Because of the applicator, usually a stiff brush, there is a danger that one slip will cause the brush to scratch the eye allowing bacteria to enter.

"We keep our sample mascara behind the counter," said Warren. "A disposable brush is used for each application. Even if a customer doesn't get enough on her brush the first time, she has to use a new brush to complete the process."

Using common sense in care and storage and paying attention to cosmetic labels will allow the consumer to get the most out of a product. If a product "smells funny" or just doesn't look like it did when purchased, it's time to throw it away.

Brushing up on makeup safety

* Keep containers tightly closed between uses.

* Store out of direct sunlight.

* Discontinue use if infection develops (especially around the eyes).

* Do not add any liquid to bring the product back to its original consistency.

* Discard makeup if color changes or an odor develops.

* Never share.

* Stringy mascara, slimy lipstick, smelly foundation -- not on this face.