Noticed a strange smell in your bottled water? There are several possible causes – some normal, and some more concerning.
In this guide, we’ve discussed the 5 most likely causes of bad-smelling bottled water. We’ve also shared the factors affecting bottled water smell, whether or not smelly water is dangerous, and what to do about bad-smelling bottled water.
📌 Key Takeaways:
- Your bottled water might smell like plastic, mildew, metals, chlorine, or rotten eggs.
- The main reasons why your bottled water might smell are contamination from plastic bottles, poor cleaning or storage, chemical disinfection, and heavy metals contamination.
- You can avoid these smells by buying water in glass bottles, switching to a reusable water bottle and cleaning the bottle regularly, and filtering your tap water at home.
Table of Contents
📋 Factors Affecting Bottled Water Smell
There are a few different factors that may affect the small of your bottled water:
- Water source. The water source determines the impurities and contaminants it contains. Some of these impurities, like iron and sulfur, may have an unwanted effect on the water smell.
- Water treatment. The method of water treatment will also affect the water smell. Certain chemical disinfectants, like chlorine and chloramine, give water a swimming pool-like smell.
- Cleaning frequency. If you use a reusable bottle, your cleaning frequency will affect the water smell. Your bottle will eventually release a foul odor if you leave stagnant water sitting at the bottom and don’t clean it for weeks on end.
- Additives & flavorings. Some water products are treated with flavorings and additives that give them a sweet or fruity smell.
👃 Why Does My Bottled Water Smell Bad? 5 Likely Causes
Here are the 5 reasons why your bottled water is likely to smell bad.
Mildew Smell: Poor Cleaning Or Storage
A moldy or mildew smell from your water bottle is likely down to poor cleaning or storage.
Reusable plastic water bottles will accumulate mildew and are susceptible to mold growth over time. After all, they’re used to store water, and the damp conditions in the bottle are favorable for microbial growth.
The way that you store bottled water may also be responsible for its weird smell. Storing water in a damp, hot location, or in a location that gets direct sunlight, may encourage the growth of microorganisms, leading to an unpleasant smell.
Plastic Smell: Plastic Water Bottles
A plastic water bottle smell comes from the bottle that the water is stored in.
Most single-use water bottles, and many reusable water bottles, are made from plastic. You might notice a plastic smell in your water if you have a new reusable bottle that you haven’t washed properly. Or, you might be able to taste and smell plastic in water stored in a single-use bottle.
Regardless of the bottle type, the plastic used in the bottle is to blame. Plastic bottles leach harmful chemicals like BPA into the water, giving it a weird taste and a plastic-y smell.
Chlorine Smell: Disinfection With Chemicals
A chlorine odor in your bottled water is usually caused by chemical disinfection during the water treatment process.
You might get a whiff of chlorine when you open the bottle because a small amount of chlorine has dissipated into the bottle air, which is released when you unscrew the lid.
Chlorine is safe in water and reduces the risk of contamination from microorganisms, but it has a smell and taste that most people find unpleasant.
Metallic Smell: Heavy Metals Contamination
If your bottled water smells metallic, it’s most likely due to minerals or heavy metals contamination.
Some bottled waters come from groundwater sources, where heavy metals like iron and zinc are naturally present. If you have sensitive taste buds, you might be able to taste even traces of these metals in your water.
Your water might also have been contaminated with metals in the manufacturing process, giving a more distinct metallic smell.
Rotten Egg Smell: Hydrogen Sulfide
Finally, the smell of rotten eggs in your water is caused by hydrogen sulfide in the source water.
Again, groundwater is most likely to be contaminated with hydrogen sulfide because this mineral is present in rocks and soils.
Most bottled water brands filter their water to remove this bad smell, but you may still be able to detect very low concentrations of hydrogen sulfide in the end product.
⚠️ Is Bad-Smelling Bottled Water Dangerous To Drink?
Bad-smelling water is typically not dangerous to drink – but the answer to this question depends on the cause of the smell.
For instance, if you can detect a mild chlorine odor, your water should be safe to drink, even if the smell is unpleasant.
But if you can smell plastic, mildew, or wet dog, your water may be contaminated with plastic chemicals or microorganisms, and may be unsafe to drink. Certain plastic chemicals have several long-term health effects, while microorganisms can make you sick.
Can’t put your finger on the cause of the bad smell? It’s best to throw out your water just in case. If you’re using a reusable water bottle, take a few minutes to properly clean the bottle, let it air dry, then taste-test the water again.
🤔 What To Do About Bad-Smelling Bottled Water
There are a few different things you can do about bottled drinking water that smells bad, including:
Buy Water In Glass Bottles Or Aluminum Cans
If you prefer to buy your water in bottles rather than drinking tap water, you can avoid plastic smells by buying water sold in glass bottles or aluminum cans.
Glass is an ideal material for storing water because it doesn’t leach anything into the water and won’t affect its smell, ensuring it retains its quality and cleanliness right up until you open the lid.
Aluminum cans are a cheaper alternative to glass. They may give water a slight metallic odor, but they’re still better than plastic bottles.
Store Bottled Water Correctly
You probably have a stash of water in plastic bottles that you can grab whenever you’re thirsty.
It’s fine to bulk-buy your water, but make sure you rotate your stock regularly according to date labels, and avoid storing your water in locations that are exposed to hot temperatures, damp conditions, or direct sunlight.
Ideally, store your water in a cool pantry and transfer it to the fridge as soon as possible. This should reduce the risk of mildew or bacteria growth that could lead to unwanted tastes and smells.
Switch To A Reusable Water Bottle
The best way to avoid a plastic smell in your water is to switch from single-use to reusable water bottles.
Ideally, avoid plastic altogether. Stainless steel water bottles are better than any form of plastic, and won’t leach any dangerous chemicals into your water.
Clean Your Water Bottle Regularly
If your reusable water bottle smells bad, you might not be cleaning it properly or regularly enough.
You can avoid drinking from a smelly water bottle by simply washing the bottle daily in warm water and dish soap. Use a bottle brush to clean the bottle all the way down to the bottom. If the smell persists, try adding a teaspoon of baking soda to the cleaning water.
Turn the bottle upside-down to air dry, so it doesn’t end up with a puddle of stagnant water that might start to smell bad.
Avoid Chlorinated Water
Some bottled waters are disinfected with chlorine. If you want to avoid any unpleasant chemical whiffs in your water, choose a water product that hasn’t been treated with chlorine disinfection.
Depending on the source, a water product may not need to be disinfected at all. Some waters are disinfected with chemical-free alternatives, like UV purification, which don’t add anything into the water and don’t affect its smell.
Filter Your Water At Home
We think the best way to avoid bad smells in your bottled water is to stop drinking this water altogether.
Instead, use a water filtration system to improve your tap water quality and remove chlorine, heavy metals, and anything else that might contribute to poor smells and tastes.
Filtering your own water supply is more cost-effective, doesn’t contribute to plastic waste, and gives you more control over exactly what your water contains.
You can choose to go all-in and remove all dissolved solids with a reverse osmosis purification system, or choose a more budget-friendly carbon-based filter to remove the most common sources of bad smells, like chlorine.
You can then take your filtered water on the go in a reusable water bottle.
📑 Final Word
An unpleasant smell in bottled water might be caused by chemicals from plastic bottles, chlorine, heavy metals, or even microorganisms.
If you notice a particularly foul smell in your water, don’t drink it. You know when something isn’t right, and it’s not worth the risk of getting sick.
Ideally, filter your water at home, and if you use a reusable water bottle, make sure it’s cleaned regularly to prevent unpleasant wet dog smells.
Why do plastic water bottles smell?
Plastic water bottles smell due to the chemicals that are used to create the plastics. BPA, BPS, and other bisphenols give plastic bottles the characteristic plastic smell. If you have a reusable plastic water bottle, this may start to smell if you don’t clean it properly and it accumulates mildew or mold, giving off a damp, wet dog smell.
Is it OK to drink water that smells like mildew?
You probably won’t get seriously ill as a result of drinking water that smells like mildew, so if you’re desperate for a drink and simply can’t wait, then you should be fine. However, we strongly recommend throwing out water that has a mildew taste because it suggests that the water is “off” or that the water bottle needs cleaning.
Why does my bottled water smell moldy?
Your bottled water probably smells moldy if you’re using a reusable water bottle that you haven’t cleaned properly or you don’t clean regularly enough. Regular cleaning with warm, soapy water should prevent your water from taking on any unpleasant odors from the bottle.
How do you keep plastic water bottles from smelling?
The best way to keep plastic water bottles from smelling is to clean them regularly. If you have a single-use plastic bottle, it’s best to throw this out and buy a reusable bottle, ideally made from stainless steel (which is less likely to smell).