Consuming water from community vending machines can increase the likelihood of cardiovascular diseases and weaken a child's bones, a health expert has warned.

Zhao Feihong, from the Beijing Research Institute of Drinking Water and Public Health, said water emitted from a vending machine is purified through reverse osmosis, which lowers its conductivity limit and defines it as soft water.

A report released by the World Health Organization in 2006 said drinking soft and purified water over just several weeks could damage a body. After the water is purified, there is an increased risk of developing cardiovascular diseases due to a low intake of magnesium, as well as potential damage to children's growing bones from a lack of calcium, Beijing Times said.

However, despite the surfacing problem, Tuanjiehu Zhonglunan community's vending machines remain popular.

"Six machines have been installed in the Tuanjiehu area and about 300 households, of 2,078 families living in the neighborhood, use the service regularly," said Yan, a sales manager from Kang Ji, a leading vending machine company.

A man surnamed Yang, who has lived in the community for more than 10 years, said water from the vending machine is better than tap water because it doesn't contain incrustations.

"Water with dissolved mineral deposits can cause kidney stones, so I don't drink tap water. However, though water from a vending machine is much better, I still don't drink it without boiling it first," he said.

Jin Shumin, who works in Tuanjiehu Zhonglunan committee, said she buys water from the machine every day.

"It costs only 1 yuan for five liters," Jin said. "I am never concerned about the quality because it has been purified eight times and the machine is checked by a water company inspector every week."

Wei Xiangdong, director of the emergency response management department with Beijing health supervision bureau, said the Ministry of Health supervises all the community machines.

"The filters and pumps are maintained and changed regularly, so residents should feel safe about the quality of the water," Wei said.