Researchers from the Barcelona Institute for Global Health (ISGlobal) studied the numbers to find how badly bottled water can impact the environment. The study focused on Barcelona, Spain, which is home to around 1.35 million people, about 60 percent of whom consume bottled water.
The scientists used a "life cycle assessment" which estimated the environmental impact of an item in its entire life span. This includes the extraction of raw materials, manufacturing, transportation, distribution, use and disposal.
The study found that if every resident in Barcelona switched to bottled water, extracting raw materials would cost over €60 million ($70.6 million). It could also lead to the loss of 1.43 animal species every year. That would be 3,500 times higher cost to the environment for resources than if the whole city were to drink tap water instead.
The researchers also found that the impact of bottled water on ecosystems is 1,400 times higher than tap water. They said that the reduction in environmental impacts should more than offset the small risk of bladder cancer that is associated with drinking tap water.
Treating drinking water generates low levels of trihalomethanes (THM), which is associated with a higher risk of bladder cancer. THM levels in drinking water are regulated in the European Union.
Cristina Villanueva, the lead author of the study, said that health reasons don't justify the wide use of bottled water. "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 that the environmental impacts of bottled water are higher compared to tap water," she said. (Related: The True Cost of Drinking Bottled Water.)
In the U.S., around 17 million barrels of oil are needed to produce plastic to meet the annual bottled water demand. In the U.K., bottled water is at least 500 times more expensive than tap water. Villanueva said that the study could help reduce bottled water consumption, but added that there should be more active policies to change the mindset that bottled water is safer.
"For example, in Barcelona, we could have more education campaigns to make the public aware that the health gains from drinking bottled water are minor compared to the environmental impacts," she said. "We need to improve access to public water, to public fountains, to public buildings where you can bring your own bottle and don’t need to buy one. We need to facilitate access to public water in public streets."
The use of bottled water has risen in the last few years because of the lack of faith in the quality of tap water. However, there have been substantial improvements in the quality of tap water in Barcelona in the last few years.
Producing plastic bottles uses about 17 million barrels of oil a year, and it takes about thrice the amount of water to make these bottles than it does to fill them.
Because plastic water bottles are made from a petroleum product called polyethylene terephthalate (PET), it takes a lot of fossil fuels to make and transport them. It also takes about 2,000 times the energy to manufacture a bottle of water than it does to produce tap water.
The negative impact of bottled water does not stop there. People in the U.S. throw away over 60 million plastic water bottles per day, or 35 billion empty water bottles per year, most of which end up as litter on the streets, parks, waterways and landfills. Of these, only 12 percent are recycled.
Plastic water bottles are not the only things that contribute to pollution in land or water. Read more about this global issue at Pollution.news.