Bottled water is 3,500 times worse for the environment than tap water

The environmental impact of bottled water is 3,500 times higher than tap water, according to researchers at the Barcelona Institute for Global Health (ISGlobal).

The consumption of bottled water has been increased globally year on year. According to previous research, this trend can be partly explained by subjective factors like taste, lack of trust in water quality and marketing by bottled water qualities. 

In order to assess the impact that this trend is having on the environment, the researchers conducted a life cycle assessment to research the damage to ecosystems and resource availability as well as the indirect impact on human health derived from the production process.

Since tap water quality may differ between cities and countries, the research team focused on the city of Barcelona. 

The results showed that if the whole population of Barcelona shifted to bottled water, the production required would take a toll of 1.43 species lost per year and cost $83.9m per year due to the extraction of raw materials. 

This is approximately 1,400 times more of an impact on ecosystems and 3,500 times higher costs compared to the scenario where the whole population shifts to tap water.

Cristina Villanueva, ISGlobal researcher and first author of the study, said: ‘Tap water quality has increased substantially in Barcelona since the incorporation of advanced treatments over the last years.

‘However, this considerable improvement has not been mirrored by an increase in tap water consumption, which suggests that water consumption could be motivated by subjective factors other than quality.

‘One of the subjective factors is the perceived presence of chemical compounds in tap water. While it is true that tap water may contain trihalomethanes (THM) derived from the disinfection process and that THMs are associated with bladder cancer, our study shows that due to the high quality of the tap water in Barcelona, the risk for health is small, especially when we take into account the overall impacts of bottled water.

‘Our results show that considering both the environmental and the health effects, tap water is a better option than bottled water because bottled water generates a wider range of impacts.

‘The use of domestic filters, in addition to improving the taste and odour of tap water, can reduce substantially THMs levels in some cases. For this reason, filtered tap water is a good alternative. Even though we didn’t have enough data to measure its environmental impact fully, we know it is much lower than that of bottled water.’

Photo by Jonathan Chng