In the latest food scare to hit China, authorities in Beijing have halted the sale of 31 brands of bottled water after they failed safety tests, the government reported.
Random market inspections found bacteria colonies in the water, the Beijing Administration for Industry and Commerce said on its website, citing a joint study with the capital's product quality bureau.
"In order to prevent these substandard products from entering the distribution chain, the product quality bureau has taken measures to halt sales," the administration said in a statement Wednesday.
Tests on one brand of bottled water -- Yiqun -- found that bacteria levels were 9,000 times above safety standards, while those in Tianxing Special Water were 560 times higher, a report in the state-run Beijing Times said.
The tests were carried out on large barrels of water and did not include the smaller bottles of water normally bought in supermarkets, the report said.
Drinking the tainted water could lead to bouts of diarrhoea, dizziness and vomiting, it added.
Part of the problems stemmed from quality controls at factories, including the failure to clean and sterilise water pipes and replace and disinfect filters, the paper said.
China is regularly hit by food scares. In 2008, authorities found that milk tainted with melamine killed at least six babies and left more than 300,000 sick with kidney stones, in a scandal that caused huge outrage.
Tainted pork, toxic milk, dyed buns, melons laden with chemicals and others have also surfaced in recent months, highlighting a lack of oversight in China's huge food industry.
In May, China's top court ordered capital punishment for food safety crimes that result in fatalities, as the government metes out harsher penalties amid rising social discontent over tainted foodstuffs.