Bottled Water Is 3,500 Times More Harmful Than Tap Water

H2-No! New research spotlights how detrimental single-use plastic water bottles are.

water bottles

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The human body is up to 60% water. These days, however, consumers have to ask themselves a very important question: What kind of water do I want my body to be made of? Although there are myriad choices—sparkling water, flavored water, and even vitamin-infused water—the two most common choices are plain-old tap water and regular bottled water. Consumers tend to believe the former is better for the environment, the latter is better for one’s health but a new study puts those assumptions to the test.

Led by researchers at the Barcelona Institute of Global Health (ISGlobal) and published in the journal Science of the Total Environment, the study compares the health and environmental benefits of three kinds of water—bottled water, tap water, and filtered tap water—in the city of Barcelona, where bottled water is becoming more popular despite recent investments in water treatment that have made the local tap water more drinkable.

The results were indisputable: Tap water is better than bottled water—both for people and for the planet.

A lot better, researchers assert. If the whole population of Barcelona decided to drink bottled water instead of tap water, they suggest, it would cost $83.9 million per year to extract the raw materials needed for bottles, production of which would cause the destruction of 1.43 species per year. Compared to tap water, that’s 3,500 times the cost of resource extraction and 1,400 times the impact on ecosystems.

The researchers note:

The higher environmental impact of bottled water was attributed to the high input of materials (i.e. packaging) and energy needed for bottled water production as compared to tap water. Indeed, raw materials and energy required for bottle manufacturing accounted for the majority of the impact of bottled water use (up to 90% of the impact in all indicators), consistent with previous studies.

But what of health? Although consumers perceive bottled water as being healthier than tap water, the scientific data don’t necessarily bear that out.

“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,” said Cathryn Tonne, ISGlobal researcher and co-author of the study with Villanueva. “The use of domestic filters, in addition to improving the taste and odor of tap water, in some cases can substantially reduce THM levels. For this reason, filtered tap water is a good alternative. Even though we didn’t have enough data to measure its environmental impactfully, we know it is much lower than that of bottled water.”

Although they hope their study will persuade some people to switch to tap water, the researchers say much larger public information efforts are necessary in order to move the needle away from the bottle and toward the tap.

The findings of the study spotlight the impact plastic water bottles have worldwide. Globally, more than 1 million plastic bottles are sold every minute. Not only does it take 2,000 times the energy to produce bottled water than tap water, but anywhere between 5 million to 13 million tons of plastic makes its way to the oceans each year. According to the Ellen MacArthur Foundation, the ocean will contain more plastic (by weight) than fish by 2050.

In the United States, in particular, more than 17 million barrels of oil are required to meet the nation's annual demand for bottled water, with 86% of plastic water bottles becoming garbage or litter.

View Article Sources
  1. Villanueva, Cristina M., et al. "Health and Environmental Impacts of Drinking Water Choices in Barcelona, Spain: A Modelling Study." Science of the Total Environment, vol. 795, 2021, p. 148884., doi:10.1016/j.scitotenv.2021.148884

  2. "The New Plastics Economy." Ellen MacArthur Foundation.

  3. "Reasons to Avoid Bottled Water." Harvard University.