Canadian study into bottled water and the results of poor regulation relative to the strict controls on tap water.
Bottled water contains more bacteria than tapwater, with some brands found to harbour levels 100 times above permitted limits, according to new research. article from the Telegraph
A team of scientists found that 70 per cent of popular bottled water brands available in shops had high levels of bacteria.
The researchers from Ccrest Laboratories in Canada found that tap water had less bacteria than bottled water. She said: "Heterotrophic bacteria counts in some of the bottles were found to be in revolting figures of one hundred times more than the permitted limit."
Dr Azam said tighter controls needed to be put on bottled water manufacturers.
"Bottled water is not expected to be free from microorganisms but the [level] observed in this study is surprisingly very high," she said.
Dr Azam said there was no need to drink bottled water if tap water was of a good quality.
"Unsurprisingly, the consumer assumes that since bottled water carries a price tag, it is purer and safer than most tap water," she added.
Dr Azam said that the bacteria in bottled water is unlikely to cause disease.
"But the high levels of bacteria in bottled water could pose a risk for vulnerable populations such as pregnant women, infants, immunocompromised patients and the elderly," she said.
Nutritionist Dr Chris Fenn said there was no need to drink bottled water in the UK because tap water was so good.
"We're lucky in this country to have good quality tap water, there are problems with the amount of bacteria found in bottled water," she said.
"And there is a huge environmental cost to all the plastic used to make the bottles which then sit in the heat."
Dr Fenn said people should drink tap water as much as possible.
"But if you are thirsty, you might be out and not near a tap so it's worth buying bottled water," she said.
"Two litres a day is the general figure but it is quite variable between people.
"Some people could be the same age and the same weight and do the same amount of exercise but still need different amounts of water to be hydrated.
"One person might drink one litre and be fine while the other person needs three litres."