Does distilled water go bad?

You’ve heard about distilled water. It’s often recommended over tap water for use in home appliances and household cleaners and even medical devices such as CPAP machines. But what is distilled water and does it go bad? This article will tell you all there is to know about using distilled water including why it goes bad and how you can prevent it.

Does distilled water go bad?

Distilled water, which comes in tight-lidded containers, has an indefinite shelf-life. It can last several years maintaining the best quality. But the purity can be compromised after that and earlier if it is not stored properly. Distilled water lasts if you keep it in a dark place away from sunlight and close the cap up tightly after any use to prevent germ infestation. 

What is distilled water?

Distilled water is a type of purified water that has been stripped of all its basic salts and nutrients such as calcium, magnesium, sodium, and any impurities. 

The distillation process involves boiling water until it becomes condensation. Unwanted minerals and such as left behind. The condensation cools and returns to water form but is now in its purest form.

Because of its ultra-pure nature, distilled water can be used for drinking, laboratory testing, cleaning medical tools, medical procedures, and cosmetics.

What is the shelf life of distilled water?

Bottled distilled water will come with a production date or expiration date printed on the bottle. Unopened distilled water will last 3 or more years after production if stored in a dark cool place and handled with good care.

Once a distilled water container is opened, it’s best to drink it within a week and store it properly during that time. If you’re using it for household appliances such as a steam iron, it can keep for another 1-2 years also if stored properly.

How to tell if distilled water has gone bad

While distilled water has a long shelf life and is unlikely to go bad, it can happen. How do you know if distilled water is no longer suitable for drinking or other use?

Distilled water that has gone bad may not be obvious. The water may taste flat because it doesn’t have any minerals in it, but that doesn’t mean it’s gone bad.

Here are some signs to look for indicating that your distilled water has gone bad:

1. Cloudy color – Distilled water should have a clear appearance. If the water looks cloudy on first appearance, it is likely contaminated with bacteria and you should not drink it. If you don’t want to throw the water away, it may still be used for household purposes that don’t need distilled water. However, it’s not advised to use it.
   
2. Pungent odor – Distilled water does not have a specific smell. Distilled water should smell like nothing, just normal mineral water. If the water smells off, then it has likely been contaminated.
   If you’re not sure whether you’re just smelling the plastic bottle or if the water actually has gone bad, pour a glass of it into any container and smell it. If it still smells odd, you can suspect that it has gone bad.
   
3. Chemical taste – Pure distilled water does not have an odor or taste, since all the minerals in it have been removed. If the distilled water has a chemical taste to it, it means the water is contaminated, and it is time to either boil it or discard it. 
   
4. Growing algae – Although algae only grow in nutrient-rich water, if you leave your distilled water out in the sunlight or open for too long, it may become the perfect environment for algae to grow and thrive in. Algae infestation is blue-green sediments floating on the surface of the water, so if you notice that growing in water, discard it without ingesting or using it.

What are the hazards of drinking expired distilled water?

Expired food is injurious to health and can give you a myriad of disorders such as having bad digestion and stomach problems. Expired distilled water is no different.

Although distilled water is normally not recommended for drinking considering its low nutrient content, consuming expired distilled water is even more hazardous for your body and can cause health problems such as stomach pains, nausea and vomiting, and diarrhea.

How to store distilled water

Here’s the best way to properly store distilled water.

1 | Keep the water in dark, cold places and avoid direct sunlight – It’s best to store the water somewhere dark such as in a cabinet to prevent algae growth. It’s also important to store it somewhere cold as bacteria grows quicker in warmer conditions.

Most distilled water today comes in plastic containers. Keeping them in the sun can warm up the plastic, making it emit chemicals that may get infused into the distilled water.

2 | Store water away from chemicals and cleaning supplies – Plastic bottles are partially permeable, so it’s best to store them away from any chemicals or cleaning supplies that have a high chemical content. This also prevents the distilled water from smelling bad.

3 | Use glass containers instead of plastic ones – Plastic is non-biodegradable and omits chemicals if used for long periods of time. If you have a choice, it’s better to use a glass container or glass bottles than plastic ones.

If you can change plastic containers, it’s recommended to use high-density polyethylene (HDPE) containers as an alternative to normal plastic containers.

HDPE tanks are made to keep your distilled water purer for longer compared to normal plastic containers. They also keep the water cooler. They are not susceptible to rusting and do not break easily upon damage. 

4 | Seal containers tightly – Once opened, seal containers tightly to prevent an infestation of algae, pathogens, or bacteria into the water. While it’s not necessary to keep opened distilled water containers, in the refrigerator, it can limit light exposure, prevent the infestation of bacteria, and taste good.

Final thoughts

Distilled water has a long shelf life of over 3 years if stored properly in a cool, dark place. This makes it a good choice to have on hand for household use and in case of an emergency.