There are many students and pupils who bring dinking water, such as water and tea which are bottled in their own water bottle at home, to the school. Since its hygiene was concerned, our last research was carried on the situation of the bacterial contaminations of those bottled waters. Then it has been found that there were serious bacterial contamination situations of those bottled water, which had made us continue the research to get more certain findings.
The results of this continuous research could make it more certain that the high level of the bacterial contamination in those bottled waters does exist. To compare to the drinking water quality standards of the water supply, more than 90% of those bottled waters were found to be incongruent, besides the contamination with Escherichia coli. The levels of the bacterial contamination found were higher in the raining season than the fall.
In this research, to investigate the cause of the bacterial contamination, some of the dinking water before bottled were collected separately to sterilized containers at the same time they were poured into the water bottle at home. As a result, the levels of the bacterial contamination of the bottled water were higher than the water which were collected separately, and it was suggested that the bacterial contamination was likely be generated by putting in the water bottle.
