During the hot days of summer, a lot of people try to find ways to stay hydrated. Some people use reusable water bottles. Others buy water in disposable bottles.

While buying bottled water may seem safer than drinking tap water, there are certain health issues related to each kind of water. There are also issues that need to be considered when buying a water bottle.

Dr. Mike Iosia, assistant professor of exercise physiology, said that the problem with bottles designed for one time use is that people often reuse these multiple times without washing the bottle. This can lead to bacteria and fungus growing in the water bottle, of which there’s a “small potential,” according to Iosia.

Another possible problem with bottled water and water bottles is leaching of Bisphenol A. This happens when the chemical Bisphenol A is released into the water from the plastic.

“The FDA has said there was no threat,” Iosia said.

He said that this release is usually caused by heating the bottle but affirmed that this could not be caused by leaving a water bottle out in the sun while exercising.

There is also a guideline people should use when purchasing a reusable water bottle. It’s based on a number system, ranging from one to seven. This number can be found on the bottom of the water bottle inside a triangle that looks like a recycle symbol.

“Try to use plastic bottles one or five,” Iosia said, “Seven is where people aren’t sure [about the safety].”

The issue with bottled water is more about the environment than the health factor. Plastic bottles take an extremely long time to decompose in a land fill. Also buying bottled water every week is more expensive than using a reusable water bottle. However, bottled water is good in an emergency such as a hurricane, tornado or if there are harmful chemicals in the water supply.

Using a water bottle with a one or five is considered safe. However, some people may be worried about the health of Cleveland tap water.

“The tap water here is really good,” Iosia said. “You don’t need a …filter.”

According to Iosia, the EPA does more testing on tap water than the FDA does on bottled water. Those interested in learning more about the safety of tap water can check the yearly report on the Cleveland Utilities Web site: http://www.clevelandutilities.com/PDF/WQData2007.pdf. Those interested in more information about FDA regulations on bottled water can go to http://www.cfsan.fda.gov/~dms/ffbotwat.html.