THE city's consumer rights protection watchdog is reminding people to disinfect drinking water dispensers more regularly after it found over 80 percent of 30 machines tested were contaminated with excessive bacteria.
A total of 25 water dispensers were found to contain excessive level of CFU (colony-forming units), 20 at alarming levels, the Shanghai Consumer Rights Protection Commission warned yesterday.
The amount of bacterial colonies found in these 20 machines reached more than 300 CFU (colony-forming units) per milliliter, far exceeding the national limit of 20 per milliliter. The machine samples were collected at an office building in Shanghai.
Experts said machines' liners are the most likely spot for bacterial contamination due to their structure.
Air enters bottles every time the drinking water flows out because of atmospheric pressure. If the air is not clean, the water inside the bottles will be tainted, leading to rapid bacterial growth. A little water may be left in the inner tank of machines, where bacteria such as dangerous E. coli can adhere.
There is no standard on the sterilization of drinking water dispensers, and the problem is commonly ignored by administrative staff members of companies and residents.
Eileen Zhu, who works for a public relations company in Xuhui District, said the water dispensers at her company are cleaned every six months, which should be once every three months.
"I feel concerned over sanitation problems as the inner tank of the machines are dipped in water for a long time, which certainly leads to bacteria," Zhu said.
Chen Jie, secretary general of the Shanghai Beverage Association, said people should become more aware of the need to disinfect the machines. They can call drinking water delivery companies to clean them.
The consumer rights protection commission reminded people to clean water dispensers every three months, and consume water in a new bottle within one week.
It is also recommended that water be heated before drinking as hot water can kill bacteria, and the remaining water inside the machine should be emptied before bottles are changed.
A total of 25 water dispensers were found to contain excessive level of CFU (colony-forming units), 20 at alarming levels, the Shanghai Consumer Rights Protection Commission warned yesterday.
The amount of bacterial colonies found in these 20 machines reached more than 300 CFU (colony-forming units) per milliliter, far exceeding the national limit of 20 per milliliter. The machine samples were collected at an office building in Shanghai.
Experts said machines' liners are the most likely spot for bacterial contamination due to their structure.
Air enters bottles every time the drinking water flows out because of atmospheric pressure. If the air is not clean, the water inside the bottles will be tainted, leading to rapid bacterial growth. A little water may be left in the inner tank of machines, where bacteria such as dangerous E. coli can adhere.
There is no standard on the sterilization of drinking water dispensers, and the problem is commonly ignored by administrative staff members of companies and residents.
Eileen Zhu, who works for a public relations company in Xuhui District, said the water dispensers at her company are cleaned every six months, which should be once every three months.
"I feel concerned over sanitation problems as the inner tank of the machines are dipped in water for a long time, which certainly leads to bacteria," Zhu said.
Chen Jie, secretary general of the Shanghai Beverage Association, said people should become more aware of the need to disinfect the machines. They can call drinking water delivery companies to clean them.
The consumer rights protection commission reminded people to clean water dispensers every three months, and consume water in a new bottle within one week.
It is also recommended that water be heated before drinking as hot water can kill bacteria, and the remaining water inside the machine should be emptied before bottles are changed.