What Are the Dangers of Refilling Plastic Water Bottles?

The use of bottled water has skyrocketed in recent years with almost 30 billion bottles sold between 2002 and 2005, according to the Container Recycling Institute. In an effort to save money and help conserve resources, you may be tempted to reuse your plastic water bottle. Don't do it unless you're willing to take certain risks related to the reuse and refilling of the bottles.

Plastic water bottles are often hard to clean, reports the University of Nebraska. This can make them prime areas for bacterial growth. The University of California states that bacteria will often "thrive" in the bottles. Also, microbiologists say water bottles can transmit dangerous diseases like the norovirus.

Plastic bottles may leak chemicals into the water when reused, especially if cleaned in a high-heat environment like your dishwasher. Most plastic water bottles are marked with a "1" signifying they're made from polyethylene terephthalate, which Harvard University says may contain antimony, a chemical that may cause cancer. More rigid bottles, like the type which contain water or fruit juice, are marked with a "3", which signifies they're made from polyvinyl chloride. Such bottles contain phthalates, which may be linked to reproductive health problems.

Although people often reuse water bottles to get the most out of the container and lower contributions to landfills, this may be counterproductive. The act of washing the water bottle for reuse eats up natural resources and puts soap and detergent into municipal water supplies. This may be just as bad as sending the bottle to a landfill, according to Columbia University's Health Services.

Many water bottles are relatively flimsy and not intended for continuous use. A refilled water bottle may break unexpectedly, leading to potential damage to clothing, electronics or anything else on which it breaks.