According to the owners of CupDepot.com, a site that sells eco-friendly products, you should reuse plastic cups. That is because it can take up to 50 years for a plastic cup to decompose in a landfill. The less cups used, the less the demand, and the less plastic will sit in landfills taking up space.

On the Other: Think of the Purpose

The main purpose of using plastic cups is to eliminate the need to wash dishes. So using this logic, the plastic cup should be kept for just one use and then thrown away. There is also a health concern related to using the same plastic cup repeatedly. Plastic cups that are classified as plastic number six (see "Which Plastics Are Safe?" in References for more information) are produced using benzene, a carcinogen that can cause illness. This chemical can "leach" or seep into the contents of the cup over time, especially in the case of warm or hot drinks.

Bottom Line

Check to see if your plastic cups are made of benzene (number six plastic). If so, it is not advisable to use the cup more than once or twice. Do not heat up the cup or place hot liquids inside it. If you don't mind washing your cups as thoroughly as you would a regular cup and you are concerned about the environment, you may want to use and wash the cup two or three times, then toss it away. If you are very concerned about the environment, avoid buying and using plastic cups altogether.

Source:

CupDepot.com; Help Save the Environment, Reuse Plastic Cups; Aug 2009

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