Reuse of water bottles

Reusing water bottles is the practice of refilling and reuse of plastic water bottles designed for one use, with tap water for multiple uses.

Reusing single-use bottles is a common domestic practice. Typically the bottle is washed out with warm soapy water after each use. Periodically a bleach solution may be employed to kill bacteria. Washing and re-using bottles cuts down on waste and landfill, and drinking tap water is much less resource-intensive than buying commercially bottled water.

Health risks from reuse by elementary school students
In 2002, a study by researchers under Cathy Ryan, a University of Calgary associate professor, appeared in the Canadian Journal of Public Health. The study was conducted on the contents of 76 water bottles obtained from students at Calgary Elementary School in Canada.

Thirteen per cent of 75 bottles contained bacteria exceeding the Canadian Drinking Water Quality Guidelines, and nearly nine per cent had fecal coliforms. Overall, more than 64% of the samples exceeded the drinking water criteria for heterotropic bacteria.

Samples of available drinking water sources showed that they were below the detection limits for these bacteria, and the researchers concluded that the contamination in the bottles probably arose from students not washing their hands, and that the students may be better off drinking from water fountains at the school.

DEHA and Diethylhydroxylamine chain letter
In 2003, a chain email was widely circulated making claims about the leaching of chemicals from plastic bottles from repeated washing, rinsing or heating. The email mentioned the chemical DEHA, which is also known as di(2-ethylhexyl) adipate. The letter was based on media reporting of a student's thesis, which was later found to be inaccurate.

Note: PET or PETE refers only to bottles with a "1" plastic recycling code.