​Let’s face it, reusable water bottles are amazing for many reasons, but they’re also great at hiding bacteria and germs.  So today, let's look at some bottles that have features designed specifically to make it easier to keep them clean.  In this post, I’m only going to cover dual wall vacuum insulated stainless steel bottles because they're some of the more popular bottle in today's market.

Here's the summary of the bottles.  Keep reading for more details about each one!

• Klean Kanteen's TKWides (easier threads to clean)
• YETI Rambler (internal threads on bottle)
• RevoMax (no threads)
• Takeya (pull tabs on seals)
• EcoVessel (pull tabs on seals)
• SmartKap (3rd party lid for YETIs that has a pull tab on the seal for the spout cap)

Before we dive into specific bottles, let's start with some general water bottle cleaning tips and guidelines.

Many bottle manufacturers state that their bottles and lids are dishwasher safe, which at first makes this seem like a great option.  Besides, why go through all the work of using a bottle brush and cleaning tablets when you can let the dishwasher do everything?

Different people will have different opinions, but here's ours.  For the most part, we do not recommend putting reusable bottles or accessories in dishwashers.

These bottles can be expensive, so we think it's better to take a hands-on approach to make sure your bottle is cleaned sufficiently while minimizing the chances that it could get damaged or chipped from knocking into something else while your dishwasher is running.  Also, you'll probably want to remove and hand-wash the seals anyways periodically because the dishwasher won't be able to get all around them.

And it's not always clear which products are really dishwasher safe.  For example, newer Hydro Flasks are dishwasher safe, but older ones are not.  For the average user, it can be confusing or difficult to really know, so we generally like to play it safe and recommend handwashing.

​Let’s move on to some bottles that have features designed specifically to make them easier to keep clean, and at the end I'll give my overall recommendation.

​There are a ton of filter bottles and accessories to choose from at this point, and while they don't help clean your bottle, they do help clean the water you'll drink so they are worth mentioning.  A few include Lifestraw, Simple Modern, and Brita.  I'm planning another post later this year where I'll compare different filter options, so I'll have much more info about this subgenre coming soon.

From an objective standpoint, it's hard to beat the LARQ bottle because UV light is proven to kill bacteria and viruses.  Of course that doesn't replace cleaning with a brush and bottle tablets, but it's an extra step to santize your water that the other bottles simply don't have.  But for over $100 for the 25oz bottle, it's understandably outside of most people's price point.

So for most people, Zulu Ace is probably the best choice.  Being able to take off both sides of the bottle makes it so much easier to make sure you're cleaning the bottle thoroughly, so we'll give the nod to this one for anyone who prioritizes cleaning your bottle over everything else.

​But ultimately, you can make any of these bottles work if you have a good brush kit, use cleaning tablets periodically, and develop a habit of cleaning your bottle often.  Now we just need someone to come out with a bottle that has a UV light, seals with pull tabs, easy-to-clean-threads, and a detachable bottom.

If you have not heard of microplastics in the past, the National Oceanic and Atmospheric Administration gives a quick recap here. (or just google "what are microplastics" and it should come up near the top of the list).

Essentially, microplastics are small pieces of plastics that are less than 5 millimeters long.  They are caused when small plastics are washed away or discarded, and they can also be created when larger plastics break down over time.  The widespread use of plastics combined with the difficult of filtering these small pieces has caused to them to become increasingly prevalent and widespread in our drinking water, lakes, and oceans.

And as you might expect, nanoplastics are similare but are even smaller.

Some microplastics with common examples include:

• polystyrene
  • foam-forms like in insulating coolers and cups, as well as packing peanuts
  • hard forms include items like some disposable razors and CD cases
• polyethylene (the most commonly produced plastic)
  • "HDPE" (high-density polyethylene) is used to make many common containers, like milk jugs and detergent bottles, as well as industrial-size products like municipal water lines
  • microbeads that are used as exfoliants in some health and beauty products, which were thankfully banned as part of the Microbead-Free Waters Act of 2015)
• polypropylene (2nd most commonly produced plastic)
  • found in many food-grade products (including many water bottle lids)
  • some clothing (though polyester has become a common replacement)

The experiment is titled "Drinking Boiled Tap Water Reduces Human Intake of Nanoplastics and Microplastics." According the the abstract, the authors claim to:

"present evidenence that polystyrene, polyethylene, and polypropylene NMPs can coprecipitate with calcium carbonate (CaCO3) incrustants in tap water upon boiling. Boiling hard water (>120 mg L–1 of CaCO3) can remove at least 80% of polystyrene, polyethylene, and polypropylene NMPs size between 0.1 and 150 μm. Elevated temperatures promote CaCO3 nucleation on NMPs, resulting in the encapsulation and aggregation of NMPs within CaCO3 incrustants."

Essentially, this means that boiling water causes the plastics to combine with calcium cabonate (aka the "hard" in "hard water" that is in most people's homes), then the combined particles then drop to the bottom, leaving a layer of cleaner water on top.

I do not have full access to the article, but I would expect two followup questions should be considered that weren't covered in the abstract.

1. Does the water need to be filtered after boiling (likely), and if so, what type of filter would be effective to remove the precipitate?
2. How does this compare to other filtration methods, such as reverse osmosis?

At BottlePro, we keep an eye out for hydration and water bottle news, then we summarize it and post it here.  Check back with us to stay in the loop!