- Toothbrush. You should replace your toothbrush every three to four months, and sooner if the brush appears to be frayed and worn out already. Always get a new brush after you've been sick, because the old one can harbor germs and re-infect you.
- Hydrogen peroxide. You need to replace hydrogen peroxide six months after opening it, but it will last for three years unopened. To test whether it is still effective, you can pour it in to the sink and see if it fizzes and bubbles. If it does, it's still good. Expired hydrogen peroxide is ineffective but not harmful.
- Insect repellent. Replace after two years unless there's an earlier expiration date on the bottle. Old insect repellent is not dangerous; it just won't work.
- Disposable razor. These razors need to be replaced every three shaves. After that, the blades can become nicked and can cut your skin. Bacteria also may develop, causing a rash or otherwise irritating the skin.
- Loofah & mesh puff. You need to get rid of a loofah after three or four weeks. Bacteria can build up in the crevices and infect open wounds or zits. A loofah also loses its ability to slough of dry skin after a few weeks. A mesh puff is more resistant to bacteria and will last up to eight weeks.
- Moisturizer. Replace after one year if opened, and after two years if unopened. Over time, bacteria can grow and cause a rash or an infection, especially with jars of moisturizer into which fingers can transfer bacteria. Moisturizers with added ingredients like alpha hydroxy acids can be even worse, because the additives can become more concentrated with age and irritate the skin.
- Sunscreen. Replace one year after opening, or on the expiration date. The danger is that as the ingredients become ineffective, and the sunscreen will not work to protect you from the damaging effects of the sun.
- Mascara. Replace mascara every three months. Bacteria that can cause conjunctivitis or pinkeye or styes can fester inside the tube.
- Sponge. Sponges should be replaced often, some say immediately after cleaning up spills. Try to use a paper towel instead, because sponges are breeding grounds for bacteria. Before us, you can heat a wet sponge in a microwave for a minute to reduce bacteria.
Many common household items do not last forever in our cabinets. Liz Vaccariello is the executive editor of Fitness magazine, the current issue of which includes an article that takes a look at the shelf life of certain household items and the health risks of keeping or using them beyond their shelf lives. She visits The Early Show Friday to share some information.
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