What is the shelf life of water?

Pure water has no expiration date and can be stored indefinitely as long as it is kept sealed in a sterile container and not exposed to air. Microorganisms can't survive in pure water, so there's nothing to spoil or degrade over time.

However, water that's not pure or has been opened and exposed to air can have a limited shelf life due to the potential growth of bacteria and other microorganisms. The rate at which water can become contaminated depends on various factors such as temperature, exposure to light, and the initial microbial load.

For instance, distilled or deionized water stored in a sealed container at room temperature can typically remain safe to drink for several months. However, once the container is opened, the water becomes exposed to air and can become contaminated within days or weeks, depending on the storage conditions.

To ensure the safety of drinking water, it's recommended to follow these general guidelines:

1. Use clean containers: Store water in clean, sanitized bottles or containers made from materials like glass or food-grade plastic.

2. Refrigeration: Refrigerating water can help slow down the growth of microorganisms. Keep opened containers or containers of perishable liquids like milk in the refrigerator.

3. Avoid sunlight: Store water in a cool, dark place to minimize the exposure to light and heat. Direct sunlight can promote the growth of certain bacteria.

4. Monitor appearance: Regularly inspect water for any changes in color, taste, or smell. If you notice any unusual characteristics, discard the water.

5. Follow instructions for perishable liquids: Some liquids, such as unpasteurized milk, may have a specific shelf life and should be consumed within a specified time frame.

Remember, the presence of microorganisms in water can lead to health risks, especially for vulnerable individuals with compromised immune systems. If you have concerns about the safety of your water, consider filtering it, boiling it, or using a water purification system to remove potential contaminants.