Bottled water might taste nicer than tap water, but the cost to the environment is so great it's not worth using it exclusively, a new study has found. 

The environmental impact of extracting it would be 1400 times worse, researchers at the Barcelona Institute for Global Health said, and cost 3500 times more. 

Barcelona's water is safe to drink, but reportedly doesn't taste the greatest because of its high concentration of calcium and magnesium, and the chlorine added to keep it clean. For this reason, bottled water has become increasingly popular in the seaside city, one of the world's most popular tourist destinations.

Scientists analysed a few different scenarios, including if everyone in the city started drinking bottled water, or stuck to tap water, whether straight out of the tap or filtered. 

"Health reasons don't justify the wide use of bottled water," lead researcher Cristina Villanueva told the Guardian. "Yes, strictly speaking, drinking tap water is worse for local health, but when you weigh both, what you gain from drinking bottled water is minimal. It's quite obvious the environmental impacts of bottled water are higher compared to tap water."

 READ MORE

• Govt to phase out single-use plastic items from late 2022
• David Seymour slams Labour Party's policy to phase out single-use plastics
• Kerbside recycling collection could be standardised nationally
• Plastic straws, stirrers, tableware and single-use produce bags to be phased out by 2025

The health impacts of drinking straight tap water were so minimal, the average life lost per Barcelona resident would just be two hours. Using filtered tap water would reduce that to about a quarter of an hour. 

"Our results support the argument that bottled water consumption should be reduced in settings where public drinking water is safe," the study, published in journal Science of The Total Environment, said. "Our findings suggest the sustainability gain from consuming water from public supply relative to bottled water far exceeds the human health gain from consuming bottled water in Barcelona."

Dr Villanueva said people trust bottled water more because "advertisers have done a good job of convincing people it's a good option" when for the environment, it isn't. 

Previous research has found "ubiquitous" levels of microplastics in bottled water, the long-term health effects of which remain unclear.