In my classes, in the halls, on the T, at the movies: Wherever I go, I see bottled water being consumed. Here are my top four reasons to go reusable and take a stand against bottled water. But these are only the facts; it’s your responsibility to make the decision.

Plastic Statistics

An estimated 165 million tons of plastic is circulating our ocean, and each year this number increases by 8 million. As for just one example of plastic’s pervasiveness in wildlife, plastic has been found in 60% of all seabirds’ digestive systems. Don’t just skim that number—think about it.

The Harm of Plastic Production

Each year, 340 million gallons of gasoline are used to manufacture plastic water bottles alone. To put this in perspective, the average American uses 500 gallons of gasoline per year for their car.

Take Your Health into Your Own Hands

Unlike tap water, bottled water is not required to adhere to government standards, and doesn’t have to disclose water testing results to the public. Harmful bacteria, chemical byproducts, and even prescription medication has been found by the Environmental Working Group* in samples of popular water brands. We don’t live in Flint, Michigan—we live in Cambridge Massachusetts, which falls well within federal and state guidelines for safe and healthy drinking water.

Money

On average, a one-liter bottle of water costs about $1, plus the Massachusetts Bottle Bill fee (yes, this is a thing), for a total of $1.05. The math comes out to $384 each year if you buy one every day. But, an 18-ounce basic Kleen Kanteen water bottle costs $18.95. This means that you can save $365 each year by going reusable! If you still aren’t convinced, let me put it another way. According to the Environmental Protection Agency (EPA), bottled water costs $1.22 per gallon. By contrast, tap water costs $0.002 per gallon, meaning that bottled water is 2,000 times more expensive than tap water.

Resources: Good Brands, Good Bottles

Avoid plastic, even in reusable water bottles! BPA-free isn’t actually safe, and so-called “reusable” plastic still breaks down over time.

• Kleen Kanteen 18oz: $18.95
• Hydroflask (insulated) 18oz: $29.95
• Sigg, Mira, Swell, Miir: similar prices

* If you are truly concerned about water safety, you can use the EWG tap water database to get the full work-up of Cambridge water, learn about the best water filters, and the best materials for reusable water bottles.

This piece also appears in our November 2018 print edition.