Welcome to Episode 1 of Water You Drinking?, the show that answers the question, “what’s in the water we’re drinking?”. In this episode, you’ll learn how to test water quality and get some background on water itself.
Sponsor: TrustInsights.ai
Water You Drinking? is sponsored by TrustInsights.ai. Imagine a world where your marketing strategies are supercharged by the most cutting-edge technology available – Generative AI. Generative AI has the potential to save you incredible amounts of time and money, and you have the opportunity to be at the forefront. Get up to speed on using generative AI in your business in a thoughtful way with Trust Insights' new offering, Generative AI for Marketers, which comes in two flavors, workshops and a course.
Workshops: Offer the Generative AI for Marketers half and full day workshops at your company. These hands-on sessions are packed with exercises, resources and practical tips that you can implement immediately.
👉 Click/tap here to book a workshop
Course: We’ve turned our most popular full-day workshop into a self-paced course. The Generative AI for Marketers online course is now available. Use discount code WATER for $50 off.
👉 Click/tap here to register for the course
Disclosure Statements
All product links provided are affiliate links. I receive a small percentage of anything you buy.
I am not a medical professional. I do not give healthcare advice. Consult your qualified healthcare provider before making changes that could potentially impact your health.
Tools Used
A/V Gear
Machine-Generated Transcript
Welcome to Water You Drinking, the show that tries to answer what's in the water that we all drink. My name is Chris. I am your water sommelier, a.k.a. mad scientist. And today we're going to talk about the basics of water quality testing at home.
Now, a couple of disclaimers up front. One, I am not a doctor. I am not a medical professional. I cannot give health care advice. Before you make any changes to pretty much anything you do in life, consult a qualified health care professional for your specific situation. Number two, I am not a lawyer. I am not an attorney. I cannot give legal advice. So if there's any kind of situation where you want to challenge something that's going on with your living circumstances or with a brand of water you're drinking or something, you need to talk to a real lawyer. I am certainly not that.
So let's talk about what you need to do to test water quality at home. Full disclosure, to specifically know exactly what's in your water, you need machinery most of us, myself included, can't afford to have at home, right? We're talking tools like gas chromatography and mass spectroscopy – big stuff, you know, the size of a refrigerator with a five or six-figure price tag.
However, there are some things you can measure at home with relatively inexpensive devices. That's what we're going through today – the tools I use to test water. Here's a philosophical perspective, because it impacts how I view water quality and how we should think about it without formal testing.
Obviously, if you have access to a lab for formal testing, you can make very specific judgments about what you do and don't want in your water. However, in general, I think of water as nothing more than H2O – two molecules of hydrogen, one molecule of oxygen – typically in liquid form. Anything in our water that isn't water is an added extra.
Sometimes those extras are good. Calcium, magnesium, and iron in your water can provide additional mineral supplementation. But other things, like arsenic, microplastics, or whatever, are bad. Without a lab, it's impossible to know exactly what's in your water.
So, the philosophy I approach water testing with for the average person like me and you is: the less stuff that's in water that isn't water, the better. Again, you may have specific medical needs that I'm not qualified to answer, but that's how I like to think about it.
There are plenty of devices you can get on Amazon. I have a "7 in 1 tester" by a company whose name I can't pronounce. And the way we do water quality testing is to take a water sample and a reference sample, then compare them – the numbers on them – to see how they turn out.
A big part of these tools, all tools actually, is calibration. That's one of the first things you have to do to make sure it's working and giving you real numbers. If you don't do that, you might be reporting on completely incorrect things.
So, what are the measures we look for in water quality? Well, there are seven of them.
Number one is called total dissolved solids (TDS). That's stuff that's in your water, you can't see it, but it's in there. If you were to take a cup of water and stir in a spoonful of sugar, the water remains clear, right? There's no visible difference. But now you know there's a whole bunch of sugar dissolved in there – that's a dissolved solid. Total dissolved solids is a measure of how much extra stuff is in the water that isn't water.
The second measure is called electrical conductivity (EC). It's measured in microsiemens per centimeter (µS/cm) and is essentially the number of dissolved ions in water. Now, if you don't remember high school chemistry, ions are simply chemicals – molecules or atoms actually – that are broken apart in the water. So, if you remember from high school chemistry, salt is sodium chloride (NaCl). When you dissolve it in water, it breaks apart into sodium ions and chlorine ions. Again, more stuff that's in water that isn't water, for the purposes of this explanation, is less good. So, electrical conductivity measures those ions and is especially good for measuring things that are metallic, because metals tend to be conductive.
Third is pH. This is a sort of acid-base indicator. The pH of pure water with nothing else in it, like distilled water, is 7.0. It goes from 1 to 14, with 1 being like the strongest acid on the planet that will eat through anything, and 14 being the strongest base that will eat through anything. So, things like vinegar would be an acid and have a low pH number below 7. Things like baking soda dissolved in water would have a high pH number like 9 or 10, on the base end. Again, we want that kind of like 7.0 or near 7, anywhere from 6 to 8 really is good, because it means there's not a lot of extra stuff throwing off the acid-base balance of the water.
Another measure is salinity, specifically, sodium and chloride within water. Your water generally shouldn't have salt in it, right? Some waters do if you have a water softener in your house. You've probably seen if you're in a home that has a water softener, it could be an apartment building, it could be a house, people are putting in large bags of salt. They are putting that in a water softener and that is what it does: it removes some types of ions like calcium and magnesium and substitutes them with sodium. Again, for some people, that's not a good thing for your health and in general, salt should not be in your water.
In recent news, there have been things like in Louisiana where seawater has entered freshwater aquifers and contaminated drinking water. Over a certain amount of salinity in the water, you can't actually get rid of the salt. This is why if you are trapped on a raft, you know, out at sea and you drink seawater, you will die because your body can't get rid of the salt fast enough compared to what you're taking in. So again, salinity, one of those things we don't want in our water.
There's a measure called specific gravity. Specific gravity is how much water weighs. Pure water is a 1.0. There's just water and nothing else. If you start adding in things like dissolved solids, chemicals, you name it, the water gets heavier in the same way that if you think about a maybe a bag full of cotton fibers, like cotton balls, and you start adding sand and stuff to it, that bag is just going to get heavier because there's more stuff in there. So specific gravity measures how much heavier the water is because there's more stuff in it.
Another measure, which is electrical-related, is oxidation reduction potential. It's called redox. And this is measured in millivolts. This is how much, how much electrical well, it measures how quickly water can essentially sanitize itself, right? High oxidation reduction potential would mean that a contaminant in it would be trapped by ions and sort of zapped out. A low oxidation reduction potential means water can't really do that. It does that through having stuff in your water with high ions, right? So even though it sounds good, it's not good for your health. Your oxidation reduction potential should be between 650 and 750 millivolts.
And finally, which is why we have the microscope here. There are some things that are inert in the sense of they're not electrically conductive. And a lot of these devices that we have at home, measure things that you can determine by essentially electricity. Some things like plastic are electrically non-conductive, right? A piece of plastic, you can stick a battery against it and nothing happens. However, it's still not good to have in your water. So the microscope is here. Because one of the things we test for is looking at the water under a microscope, and trying to determine how much extra stuff we see that shouldn't be there, little things floating around. So that's how we test for this.
Now let's go through some of the processes and procedures for home water testing. First thing, we need your water to be roughly at the same temperature. It can be any temperature you want, but things like pH change with changes in temperature. Now, the swings aren't huge, but they can be enough to throw off results if you're comparing two different bottled waters, one really cold and one room temperature.
I have here triple-distilled, triple-filtered reverse osmosis water. Reverse osmosis is a machine very similar to distilling water. It basically takes a bunch of stuff out, deionizes the water, filters it for bacteria and viruses, and dissolves solids and all that stuff. What you end up with is pretty close to distilled water. It's not exactly the same, but it's pretty close. You can use actual distilled water for this test if you want. Just go buy a jug at the supermarket. But for what we're doing here, reverse osmosis run through the machine three times is good enough.
Let's talk about calibration first, no matter what instrument you buy. If you're interested in the tools I'm using, there's a link in the description to them on Amazon. The first thing we want to do is calibrate. I'm going to move aside some stuff and put some of the reverse osmosis water in some of these metal bowls, just as cleaning bowls.
Now we have here all-purpose vinegar, this is white wine vinegar from Heinz. It doesn't really matter who makes it, what matters is the strength. It says this has been diluted with water to a cleaning strength of 6% acidity. Now, 6% acidity for white vinegar works out to a pH at roughly room temperature of about 2.3. So if you've got vinegar and a meter that can test it, you'll want to take the meter first, as always, and wash it off. Make sure there's nothing sticking to it that shouldn't be there. Use your cleanest water available to rinse it. Then stick it in the vinegar. What you should see is it should go to about 2.3. If it doesn't, or if it's off, then you want to calibrate if your meter allows it. You can calibrate it down to get it set to what it's supposed to be at. So we are at 2.2, 2.2, 2.3. Okay, there we are at 2.3. This is good. This means the meter is working as intended.
Alright, so we'll put our vinegar aside here. Again, after you do any kind of calibration, wash off the meter and then dump your washing fluid so you can pour new. So now we know our meter is working correctly.
The next thing we want to test is some tap water. I have some regular tap water from my house. I live in the metro Boston area, and most of the water in this area comes from the Massachusetts Water Authority. It all comes from one big system with disinfectant products and other things to make the water safe to drink.
One general truth about water treatment is that it uses chemicals to clean the water and remove things that can cause obvious sickness like bacteria, viruses, spores, and molds. This, in turn, can create byproducts in the water. Disinfectant byproducts can make water less healthy to drink. However, it's important to be clear: these byproducts are much, much less harmful than the bad things like E. coli. It's safer to drink water with byproducts than water contaminated with E. coli.
Disinfection is essential, but it still leaves things in the water that aren't ideal. So, if you have the resources, consider getting a water filter to remove that stuff if you prefer water with less in it.
Alright, we've got everything cleaned and ready. We'll take two containers. We'll start with the reverse osmosis water on the right and call out the measurements as we take them.
The pH of this water is 6.6. Why isn't it 7? Part of the reason is that during the reverse osmosis process, the water is exposed to air containing carbon dioxide. The more agitated the water, the more naturally acidic it becomes because it absorbs CO2 from the atmosphere and creates carbonic acid. This is why seltzer water is acidic – the CO2 makes it bubbly and fizzy.
So, our reverse osmosis water comes in at 6.5 for pH. Now let's check the micro Siemens per centimeter: 5. That's very good – there's very little in this water. Our total dissolved solids are 2 parts per million, which is also very good. There's very little in here. Salinity is zero, as expected. Specific gravity is 1.0. And our oxidation reduction potential is very low at 395. This water would be a bad idea for an aquarium because the low oxidation potential means algae and mold would grow quickly. Good for drinking, bad for an aquarium!
That's our reverse osmosis water. Let's put it aside and move on to the tap water.
Next, let's take our tap water at the same temperature.
Our first check is the pH. This tap water comes in at 8.1, which is a little more on the basic side. It's not bad, but it's more basic than the reverse osmosis water, likely due to disinfectant byproducts.
Our second measurement is electrical conductivity, measured in microsiemens per centimeter. We have 202, indicating a fair amount of dissolved solids in this water.
Total dissolved solids are 101 parts per million, more than 50 times the amount in the reverse osmosis water. Salinity is 0.01%, not much compared to seawater (3%), but there are some sodium ions present.
Specific gravity is 1.001, meaning there's something in here besides just water.
Interestingly, the oxidation reduction potential is lower, at 262 millivolts. I'm not sure why it's lower, but it's definitely different from the reverse osmosis water.
Let's clean off the probe and turn it off.
Our last test is for particles. We won't bother with the reverse osmosis water, as its filtration system removes dissolved solids and likely any particulates.
Remember high school biology or chemistry class? We're going to take a look at this under a microscope.
(cleans slide)
We'll use one coverslip and quickly visually inspect for anything unusual. Then, we'll take one drop of water from a clean pipette and place it on the slide with the coverslip. Now let's put it under the microscope.
We're looking for anything in the water, and we want to make sure we're centered.
(adjusts microscope)
I'll count the number of things within the field of view at 160x magnification, excluding water bubbles.
There should be zero, but at the very top, I see one, two, three, four, five, six, seven, eight... a large, noodle-shaped object! Nine, ten, eleven, twelve... about 20 different objects at this resolution. Some are very small, requiring closer examination to confirm they're not water bubbles, but some are quite large.
This one here is definitely a microplastic. It's a long, elongated object, like a clear french fry or a piece of fiber optic plastic. That's definitely not supposed to be there! There are other clear microplastics here, too, chunky pieces that don't look like bacteria or spores. They're not biological.
So, we found about 20 microplastics in this sample.
Remember, always calibrate your device, test your reference solution (the reverse osmosis water in this case), and then test your subject (the tap water). For this test, we used seven electrical-based measures plus the particulate measure to find out what's in the tap water.
When you're done, like we're doing here, enter your results in a spreadsheet. I'll put the spreadsheet in the show notes so you can see what we tested and track results over time.
I wanted to go through the basic testing process as a reference for future episodes, so you know what we're testing, why, and what the numbers mean.
Thanks for tuning in! We'll talk to you in the next one.
(music)
Yessssssssss! ~ Brooke
Great idea to do this show. The microplastics issue is so disturbing already. We are all consuming so much of it in what we drink, eat and breathe.
Would be good to see a comparison of quality between Tap Water and bottled water. I would imagine little difference though people would be freaked out by the microplastics in all water... Do you think a typical reverse osmosis filter will remove some % of microplastics?
https://insideclimatenews.org/news/10012024/plastic-in-food-and-bottled-water
https://www.onegreenplanet.org/human-interest/research-finds-that-90-of-burgers-steaks-chicken-and-plant-based-food-contain-microplastics
https://news.oilandgaswatch.org/post/plastics-boom-brings-flood-of-new-ethylene-cracker-chemical-plants-despite-frequent-environmental-violations
Thanks again for the interesting content. I always thought that once we all new that plastic was everywhere we would start to throttle the production of it.
Sadly not true at all - cracker plants growing like crazy still
Gary