That mascara wand can do more than just make your lashes longer. It can also give you an eye infection.

Every year, many women end up with eye infections from cosmetics. In rare cases, women have been temporarily or permanently blinded by an eye cosmetic, according to the FDA.

Eyelashes naturally have bacteria on them. As soon as you use a makeup brush on the eyelash or eyelid, the brush is contaminated, according to experts.

Over time, the infected brush leads to a buildup of bacteria in the cosmetics container. This increases the chance for an eye infection or an allergic reaction with each use of the product.

Pieces of makeup can land in the eyes and cause redness and irritation. More serious infections that threaten sight can result if the surface of the eye is scratched with an infected brush or makeup pencil.

Most cosmetics have long shelf lives. But since they can be infected with bacteria after only one use, it is a good idea to keep track of how long you have been using products like mascara and eyeliners. Although there are no guidelines for cosmetics use, risk of infection can be reduced if you change them every 3 to 4 months, experts suggest.

Also, don't share cosmetics. Cross contamination happens when two or more people use the same brushes or eyeliners. The main danger with sharing makeup is passing on an infection like viral conjunctivitis, also known as pink eye. Exposure to even a small amount of virus can lead to a very uncomfortable infection.

If you have signs of a viral infection, make an appointment with your eye doctor. Signs include:

• Discharge
• Swelling of the eyelids
• Inflammation of the white of the eye

The FDA offers the following tips for the correct use of eye cosmetics:

• Immediately stop using eye products that cause irritation. If irritation persists, see a doctor.
• Wash your hands before applying eye cosmetics. If you don't, the bacteria on your hands could cause an infection.
• Make sure that any cosmetic tool you place near the eye is clean.
• Don't allow cosmetics to become covered with dust or infected with dirt or soil. Wipe off the container with a damp cloth if you can see dust or dirt.
• Don't use old containers. If you haven't used the product for several months, it's better to throw it out and buy a new one.
• Don't spit into eye cosmetics. The bacteria in your mouth may grow in the cosmetic and later use may cause an eye infection.
• Don't share your cosmetics. Another person's bacteria in your cosmetic can be harmful to you. Don't use "testers" in retail stores where others are sampling the same product unless you are sure they have been tested with single use applicators.
• Don't store cosmetics at temperatures above 85°F (29°C). Cosmetics held for long periods in hot cars, for example, are more at risk of causing infection due to the preservative becoming weak.
• Don't use eye cosmetics if you have an eye infection or the skin around the eye is red. Wait until the area is healed.
• Take extra care in using eye cosmetics if you have any allergies.
• When applying or removing eye cosmetics, be careful not to scratch the eye.
• Don't apply eye makeup while in the car or bus. If you come to a sudden stop or bump there is a risk of injury to your eye.
• Don't use glitter, metallic, or sparkle makeup. Flakes can fall into the eye and cause irritation or infection.
• If you wear eyelash extensions, have a professional in a sanitary setting apply them. That means an experienced aesthetician who uses chemicals that are safe for your skin.