We're losing our taste for bottled water with sales on the slide

Consumer group Which? believes the industry is on the slide amid concerns it is expensive, bad for the environment and has little, if any, taste advantage.

Half the population can't taste the difference between bottled and tap water, according to a study from Which?

Water of life: But bottled water comes as price and is losing popularity with the public

This Water blackcurrant flavour was criticised for sugar content

Almost one in five - 18 per cent - said they actually preferred the flavour of tap water.

'There's no contest when it comes to the cost,' said a Which? spokesman.

'At 0.22p a litre, tap is 141 times cheaper than the best-selling mineral water, Evian, which costs 31p a litre in a supermarket.'

The consumer group also highlighted a marketing push for expensive fruit-flavoured waters. But rather than being healthy, some contained up to seven teaspoons of sugar.

Researchers at the food and health group Sustain picked out This Water - formerly known as Innocent Juicy Water (pomegranate, lychees and blackcurrant flavour). It had the equivalent of seven level teaspoons of sugar per 420ml bottle.

Britons spent £1.68billion on 2.275billion litres of bottled water in 2006 but there are signs that our thirst is drying up. Nearly a quarter of those surveyed by Which? said they were drinking less bottled water than a year ago. According to one market research agency, sales dropped by 9 per cent last year.