Water usage in the lab: we cannot do without this precious blue resource – but we can do a lot better

Washing and rising of items in the lab - What you can do better!

Water is essential to life on Planet Earth and therefore, an extremely precious resource. Sadly, water scarcity affects every continent and according to the UN, an estimated 1.42 billion people – including 450 million children – live in areas of high, or extremely high, water vulnerability. That’s both heartbreaking and scary!

This is why it’s important to use water wisely – especially in the lab: research labs are extremely water-intensive and you’re most likely consuming much more water in the lab than you are at home.

My name is Nikoline Borgermann, I work as an independent green lab consultant, and here’s what you can do to reduce water consumption in your lab.

 

Two devices that consume loads of water, but can easily be replaced

One of the processes that can contribute heavily to the water consumption of labs is condensation. Conventional condensers are water condensers, and these promote condensation of vapors and gasses by passing cold water around them. That’s quite an efficient mechanism – but really not ideal in terms of water consumption and water accidents …

Water condensers typically consume 30 liters of water per hour – and since condensation can take a while, condensation reactions can run for several hours or even overnight. This means that 1) enormous amounts of water are poured down the drain and 2) water leaks can result in serious flooding and damage to the lab.

That was the bad news. The good news is that you can get waterless condensers! Such condensers are twisted and turned in a way that promotes condensation of vapors and gasses by the surrounding air. Brilliant, right?

By using waterless condensers, you are not only drastically reducing water consumption – you are also mitigating the risk of water leaks and floods damaging your lab. So without promising too much, I think your facility manager will love you!

 

Another lab apparatus that consumes massive amounts of water is the water aspirator.

Water aspirators are connected to sink faucets and create vacuum as water flows through a narrowing tube. And while these tiny devices may be cheap to buy, they come with a massive water bill! A water aspirator needs at least 4 liters per minute to do its thing – and probably uses double. If a water aspirator is used on average, for just one hour per day, this adds up to a minimum of around 90,000 liters per year. That’s more or less the same amount of water contained in a water tank that measures 7 meters high and 8 meters in diameter (!).

Luckily, an alternative is available for this too: instead of a water aspirator, you can use a vacuum pump. So, in the name of water conservation you might wish to consider getting yourself such a pump for your suction and filtration work.

In addition to condensation and vacuum creation, there’s another process that deserves mentioning, and that’s autoclaving! Autoclaving is used to sterilize reagents, utensils and waste – and it’s indispensable for bioscience research. Unfortunately, autoclaving too consumes massive amounts of water (and energy)! You can read more about autoclaves and how to reduce their environmental footprint in our previous article: Energy Consumption

 

Ultrapure water is unfortunately not only pure, it’s also wasteful

Water comes in different flavors – also in the lab. Some of the different types of water used in a lab are tap water, deionized water, and ultrapure water. These water types have different purities in terms of minerals and microorganisms and therefore serve different purposes. Certain procedures in the lab need ultrapure water, while others don’t.

The use of deionized water can compromise one experiment, but not the other. So why is this important? Why don’t we use ultrapure water for all activities in a lab, just to be on the safe side? Well, if the environmental impact and price of the different water types was the same, maybe we would all use ultrapure water for everything in the lab. But that’s not the case; with a higher purity of water comes a higher price, and a much higher environmental impact!

I used to think that when 1 liter of tap water entered an ultrapure water purification system, 1 liter of ultrapure water would come out.

Boy, was I wrong: Depending on the purification technique of the system, it may take up to 5 liters of tap water to produce 1 liter of ultrapure water! So basically, that means that you’re pouring 8 liters of tap water directly down the drain every time you fill up a 2-liter blue cap bottle with ultrapure water. Yes, eight liters!

This is why it’s important to consider which kind of water is needed in your lab work. Are you using ultrapure water where it isn’t needed? And are you using a little too much nuclease-free water? This will not only have been processed, it has also been bottled in plastic and transported to your lab!

Using the right purity of water makes a huge difference in terms of water consumption, and there may very well be great green (or blue) potentials in your habits.

An example: when you are making running buffers, wet transfer buffers and blocking buffers for western blotting, the odds are that deionized water will do the job for you. It certainly did in my previous lab! The same goes for phosphate-buffered saline (PBS) and the like, when rinsing coverslips and harvesting and washing cells for most biochemical assays.

So consider if you could use less ultrapure water in your experiments – and remember to take good care of your ultrapure water purification system to prolong its life time!

 

The washing and rinsing of items in the lab: we cannot do without, but most of us can do better

It’s simple, but it’s true: reducing the amount of water when rinsing and washing utensils in the lab can make a huge difference. In a normal day in the lab, I would turn on the tap many, many more times than I would at home. And not only that, I also had to double rinse things. First, I would rinse in tap water (which is loaded with minerals in Denmark!), and then I would do a quick rinse in deionized water to prevent calcium deposits. And while this double-rinsing procedure is absolutely needed in many – if not all – labs, it clearly shows the great potentials of reducing the flow rate of the water and/or the duration of rinsing. Think about it: How many times do you rinse utensils or other lab items in one day? What if you used 10% less water every time? What if your lab mates did the same? It all adds up to an incredible amount of our most precious blue resource!

 

It isn’t rocket science to reduce water consumption – but it sure can be tricky

So, you can appreciate that it really isn’t rocket science to reduce water consumption in the lab.

By switching to waterless condensers and vacuum pumps, for example, you have already done a lot.

Unfortunately, purchases and technological hacks cannot do all the work for us. If we want to drastically reduce the water consumption of labs, we must change some habits too.

And while changing habits is definitely possible, it isn’t always easy. It takes time and effort to switch to other purities of water in experiments, and to reduce the amount of water used for rinsing your items. But once you have nailed it, you will be automatically – and effortlessly – taking impactful, green and blue actions on a daily basis.