How Long Does Bottled Water Last?
Bottled water is a common household staple, favored for its convenience, portability, and reliability in emergencies. However, as with any consumable product, it’s important to know how long bottled water lasts and whether it is safe to consume past a certain date. Unlike many food products, bottled water doesn’t spoil in the traditional sense, but its quality and safety can be affected by the environment it’s stored in, the type of water, and its container.
Understanding Expiration Dates on Bottled Water
Many people are surprised to learn that bottled water typically has an expiration date printed on the label. This can be confusing because water itself doesn’t spoil. The expiration date, however, isn’t a reflection of the water’s quality but rather the packaging. Over time, plastic bottles can leach chemicals into the water or deteriorate, affecting the taste and potentially the safety of the water.
In most cases, the expiration date on bottled water is set by the manufacturer as a guideline for optimal taste and quality. The FDA does not require bottled water to have an expiration date, as water is a naturally occurring, non-perishable resource. However, the containers, especially plastic ones, may degrade over time, which is why a date is included.
The standard expiration period is usually two years from the date of bottling, but this doesn’t mean the water becomes unsafe to drink after that time. Rather, it’s an indication of when the manufacturer believes the product’s quality, including taste and appearance, will be best, but if kept in the right container or type of plastic, the water could be safe to drink for years after the expiration date.
Shelf Life of Different Types of Bottled Water
Not all bottled water is the same, and the type of water you buy can affect its shelf life. The main types of bottled water include:
Spring water
Purified water
Mineral water
Distilled water
Flavored or enhanced water
1. Spring Water
Spring water is sourced from natural springs, often from underground aquifers. Since it’s minimally processed, spring water can retain more natural minerals, which some consumers prefer for the taste and health benefits. In terms of shelf life, spring water in plastic bottles is subject to the same guidelines as other bottled waters. It can technically last indefinitely, but for optimal taste and quality, it’s best consumed within two years of bottling.
If stored improperly, spring water can absorb odors or chemicals from its surroundings, especially if the bottle is plastic. Therefore, storing it in a cool, dark place is crucial.
2. Purified Water
Purified water undergoes processes like distillation, deionization, or reverse osmosis to remove impurities. This type of water typically has a longer shelf life than minimally processed water, as most contaminants and minerals have been stripped from it. Like spring water, purified water can last indefinitely if stored in the right conditions, but for the best quality, it should be consumed within two years.
Purified water is less likely to change taste or appearance over time, but it is still important to keep it sealed and in an appropriate environment.
3. Mineral Water
Mineral water is sourced from mineral springs and contains a variety of dissolved minerals such as calcium, magnesium, and sodium. These minerals give the water its unique taste and can also contribute to its shelf life. The minerals in the water are stable and don’t break down, so mineral water can last indefinitely if stored properly.
However, it is still recommended to consume it within two years for the best quality. After the expiration date, the taste of mineral water may begin to change, and there’s a slight possibility of mineral precipitation, which is where the minerals can solidify in the container in a similar way to how limescale forms, though it remains safe to drink.
4. Distilled Water
Distilled water is created by boiling water and then condensing the steam back into a liquid, leaving impurities behind. It is often used in laboratories, for medical purposes, or in appliances like humidifiers due to its purity.
Because distilled water is free from minerals and other substances, it has an almost indefinite shelf life when properly stored. As with other types, the key factor is the bottle it’s stored in, as plastic can degrade over time. To maintain its purity and taste, distilled water should be consumed within two years, although it will remain safe for much longer.
5. Flavored or Enhanced Water
Flavored or enhanced waters contain additional ingredients, such as vitamins, electrolytes, or flavorings, which can significantly affect their shelf life. Unlike plain bottled water, these products can spoil because of the added components. Flavored waters generally have a much shorter shelf life than plain bottled water and should be consumed by the expiration date listed on the packaging. After this date, the added ingredients may break down, affecting both taste and safety.
(Take it from Jeremy the Camel, a water storage expert who wouldn’t risk drinking bottled water after its 2-year expiration date)
Factors That Affect the Shelf Life of Bottled Water
1. Storage Conditions
Proper storage is the most important factor in determining how long bottled water will last. Ideally, bottled water should be stored in a cool, dark place, away from direct sunlight, chemicals, and strong odors. Sunlight and heat can accelerate the breakdown of the plastic, potentially leading to the leaching of chemicals like antimony or bisphenol A (BPA) into the water.
Heat can also promote the growth of algae or bacteria if the bottle is not properly sealed or if it has been opened. Storing water in a place that’s free from strong odors is also important because plastic bottles can absorb and transfer these smells into the water, altering its taste.
2. Bottle Material
The type of material the bottle is made from will also affect how long the water can last. Most bottled water comes in plastic bottles made of polyethylene terephthalate (PET) or high-density polyethylene (HDPE). These plastics are lightweight and durable but can leach chemicals into the water over time, especially when exposed to heat.
Glass bottles offer an alternative, as they are impermeable and don’t react with the water, meaning the taste and safety of the water remain intact for much longer. However, glass bottles are heavier, more fragile, and less common for everyday bottled water.
3. Exposure to Sunlight
Sunlight can degrade plastic bottles over time, causing them to break down and potentially release chemicals into the water. Bottled water stored in direct sunlight may also become warmer, which can promote the growth of bacteria or algae, especially if the bottle has been opened.
For these reasons, bottled water should be stored in a cool, dark environment. If bottled water is left in a car or another hot area for an extended period, it may not taste as good and could pose a slight health risk due to the breakdown of the plastic.
4. Whether the Bottle Has Been Opened
Once a bottle of water has been opened, its shelf life is significantly reduced. Open bottles can become contaminated with bacteria from your mouth, hands, or the environment. After opening, it’s best to consume bottled water within a few days for optimal safety, especially if it’s stored at room temperature.
Refrigeration can help slow down the growth of bacteria, so keeping opened bottles in the fridge is a good practice. However, even refrigerated water should be consumed within a week to avoid the risk of bacterial growth.
The Impact of Plastic on Water Quality
Plastic bottles are convenient and cost-effective, but they do have drawbacks when it comes to long-term storage of water. One of the biggest concerns is the potential for chemicals like BPA or antimony to leach into the water. While most bottled water manufacturers have moved to BPA-free plastics, other chemicals in plastic can still leach into the water over time, particularly when exposed to heat or sunlight.
The longer water sits in a plastic bottle, the more likely it is that these chemicals will start to leach. This is one of the reasons why consuming bottled water within two years is generally recommended, even though the water itself doesn’t spoil.
For long-term water storage, it may be better to use glass bottles or specially designed plastic containers made for water storage. These containers are often thicker and made from plastics that are less likely to leach chemicals over time.
Best Practices for Storing Bottled Water
To ensure that your bottled water remains fresh and safe for as long as possible, follow these storage tips:
1. Store in a Cool, Dark Place
Keep bottled water away from direct sunlight, heat, and strong odors. A pantry, closet, or basement is a good option.
2. Use Glass for Long-Term Storage
If you’re planning to store water for emergencies or long-term use, consider using glass containers or specially designed water storage containers.
3. Keep Bottles Sealed
Unopened bottles have a much longer shelf life than opened bottles. Once you’ve opened a bottle, refrigerate it and aim to consume it within a few days.
4. Rotate Your Stock
If you store bottled water in bulk, especially for emergency preparedness, make sure to rotate your stock. Use the oldest bottles first and replace them with newer ones to ensure freshness.
5. Check for Changes in Appearance or Taste
If bottled water has been stored for an extended period, check for any changes in appearance, such as cloudiness or particles, or a strange taste. If the water seems off, it’s better to get rid of it instead of risking an illness.