Bottled water

Photo Courtesy: [Daniel Orth/Flickr] / CC BY-ND 2.0

Billions of gallons of bottled water are sold every year in the United States. Does it ever go bad or expire?

The United States is the world’s largest consumer of bottled water. In 2018, 13.85 billion gallons of bottled water were sold in the U.S and that’s a lot of H20. In fact, on a per-person basis, only three countries on Earth drank more bottled water: Italy, Thailand, and Mexico.

With this kind of consumption, there are a few questions that come up about the bottled water industry. Things like: Where does the water come from? Which brand is healthiest? What’s the difference between mineral water, spring water, and distilled water? But here’s a couple more: Does it ever go bad? Are the expiration dates on the packaging relevant? Let’s find out.

Why does bottled water have an expiration date?

The United States Food and Drug Administration (FDA) deems its bottled water has an “indefinite shelf life” as long as it is produced under its “current good manufacturing practice” guidelines and is stored in an unopened and properly sealed container. (Keep those words in mind. We’ll come back to them.) That distinction is important because water doesn’t go bad on its own but requires other biological materials like germs, bacteria, etc. to be present in order for spoilage to occur. On that basis, the FDA does not require that expiration dates be placed on bottled water.

In 1987, New Jersey’s state legislature passed a law requiring that expiration dates be placed on bottled water. A standard two-year expiration date was imposed. As it turned out, the legislature repealed that law in 2006, making New Jersey’s rules the same as the FDA’s. Having said that, some manufacturers have kept on putting date codes on their bottled water once they started doing it to satisfy New Jersey lawmakers. That’s one reason you see expiration dates on bottled and packaged water even though it’s not technically required. 

Who is using the expiration date?

Have you noticed dates on the packaging of your preferred brand of bottled water? The manufacturer may be continuing to put dates on their water voluntarily despite the repeal of New Jersey rules requiring it. For many manufacturer’s it’s become just the ordinary course of business even though it’s not particularly relevant to the product, or required by law. Any date that does appear may have nothing to do with the water per se.

An unopened and properly sealed bottle of water has an indefinite shelf life. Great news! But what good is an unopened and properly sealed bottle of water on the shelf indefinitely?

The International Bottled Water Association (IBWA) has explained that those date codes are often put on the packaging to help with inventory management. The codes help retailers to know when to rotate product, when to restock product, and how to ensure that they’re always presenting the most recent packaging.

It’s interesting to note that those dates and other data may also have actually been intended to show up on the packaging of soda or other products. Most water bottlers also package other beverages, and they often use the same machine systems for labeling and packaging various products.

Now, about those words “unopened and properly sealed container”

An unopened and properly sealed bottle of water has an indefinite shelf life. Great news! But once that bottle of water is open and you put it to your mouth — whole new ball game. That water, per se, won’t go bad. But it won’t indefinitely be good to drink.

An open bottle of water that has been even partially consumed is exposed to germs and food particles that could cause spoilage. Backwash is real, changes the equation when it comes to bottled water spoilage. An open bottle of water — exposed to contamination — is no longer good forever.

In 2018, 13.85 billion gallons of bottled water were sold in the U.S. This is a lot of H20. In fact, on a per-person basis, only three countries on Earth drank more bottled water: Italy, Thailand, and Mexico.

The IBWA recommends finishing that bottle of water in a single serving (well, of course, they would) and presumably grabbing another. Or, they suggest refrigerating that partially consumed bottle of water to slow down the growth of any bacteria. Bacteria do not reproduce as quickly in cooler temperatures.

Keep in mind also that an opened bottle of water sitting about is going to get flat (if it had been carbonated in the first place) or begin to taste stale after a few hours. Prolonged exposure to the air changes its pH level (exposure to air makes the water slightly more acidic) and its chlorine content, too. Exposure to dust and microbes drifting about the air will also affect that taste of the water. While the bad taste isn’t a sign of the water going bad, it is a sign that the water is no longer at its best.

Important notes about packaging and storage

There’s every reason to pay attention to the dates on the bottles of water. And, if you disregard the dates or aren’t aware of them, there are reasons to be worried. Single-use bottles of water are made of high-density polyethylene (HDPE) or polyethylene terephthalate (PET). HDPE is a slightly porous product that can absorb smells from its environment, which smells can be picked up by the water in the bottles. As Dr. Sam Beattie, a food safety specialist at Iowa State University told

I’m not aware of any issue that would make them nonconsumable. But just to be cautious, you probably shouldn’t store your bottled water near gasoline, paint, or other noxious chemicals.

Some transfer of chemicals from the plastic container into the water is also possible, though the FDA reports that the levels transferred are within safe margins. Having said that, those chemicals break down faster in heat, so bottled water should never be stored in direct sunlight or in your car on a summer day. 

Man selling water on the side of the roadMan selling water on the side of the road
Photo Courtesy: [Huseyin Akuzum/Unsplash]
There have been reports linking from bottles left in the sun (and presumably the release of chemicals from the plastic into the water) with breast cancer in women, and with other types of cancer in both men and women. 

In the August 2014 Time Magazine article entitled “You Asked: Can Water Go Bad?”, Dr, Kellogg Schwab of the Johns Hopkins University Water Institute said: “A chemical called bisphenol-A, or BPA, along with other things used to manufacture plastic can leach into your water if the bottle heats up or sits in the sun.” BPA is a hormone disruptor that research has tentatively linked to several health hazards, including heart disease and cancer.

The passage of time, though, does not seem to increase the risk. Reports indicate that exposure to leached chemicals is the same whether you drink from a freshly bottled bottle of water, or one stored for some time (hopefully not near any paint cans).

Eight tips for maximizing the healthy life of water

Water that is stored properly and kept from getting contaminated one way or the other will not go bad or expire. Having said that, water doesn’t always taste as fresh as it can be. How can we maximize the healthy life of water, and keep it as refreshing as possible? Here are nine tips.

  • If an uncovered glass or partially drunken bottle of water has been sitting out for a few hours or overnight, don’t consume it.
  • If you’re cleaning a water bottle to re-use it, let it dry completely — with the cap off — before using it again.
  • Do you use a refillable water bottle like those made by Nalgene? They should be washed at least once daily.
  • Don’t store your water — even if it’s sealed in its original bottles — in intense heat, direct sunlight, or near household chemicals.
  • Once you’ve opened and started drinking a bottle of water, refrigerate it if you want to finish it later.
  • Don’t re-use water bottles or even glasses without cleaning them first.
  • Consider glass, glass-lined and, stainless steel bottles if chemical leaching is a particular concern.
  • There are several brands of reusable water bottles with filters incorporated into them if tainted water is a particular concern.

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