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Comment by datascienced | Hacker News Reader

RO is cheap enough for middle class or above (order of magnitude is ~ what you might spend on uniforms and excursions for a kid in a state primary school). Assuming a self install. So it is a good option if you can afford it. Maybe RO becoming part of the standard set of things you buy (washing machine, vacuum cleaner etc.) is the way. You have to keep up to date with filter changes though.

RO typically needs a post filter. Hopefully that doesn’t add any bad chemicals. But you need it as pure water is desperate to bind, so you can either bind it to something you choose, or bind it to whatever pipe work / tanks are beyond the filter. Also you might want a higher ph.

Maybe some disruption to make a nice looking, compact and cheap and zero install RO unit would be good and some subsidy for people without the means to buy one who live in risk areas. Plus subsidy for maintenance.

If the design is like a printer where you pull out and push in new cartridges and have warning lights it will make maintenance easy.

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A recent study (made it to HN) used a novel sensor to count microplastics in bottled water. The numbers were 10x higher than expected, but the real surprise was that 50% were shed from the plant filtration system.

I’m guessing RO is similarly bad (the membrane is made from one of the plastics in question).

I have been buying 5gal water jugs from a local Seattle company until recently, with the articles on all the microplastics shedding from the bottles into the water inside.

I did buy no-plastics Aarke glass/steel carbon filter pitcher for my drinking water.

It's hard to find water filtration without plastic involved, hopefully other options will come to the market, but their offering is pretty good so far.

>It's hard to find water filtration without plastic involved, hopefully other options will come to the market, but their offering is pretty good so far.

What about distillation as a filtration method?

Are the micro/nano plastics filtered by distillation?

Interesting what method of filtration the chip factories use, as they need 100% pure water for the cpu making process.

I've been drinking distilled water for a few years now, and the quality and peace of mind have been great. I documented it in https://www.nayuki.io/page/drinking-distilled-water .

Its not that interesting. Distillation works but its not healthy to consume. You could distill the water without plastics involved but then you need to add back minerals before drinking.

Debunked urban legend. Likely retcon from various mythology involving the chemistry lab's "deionized water" bottle which every chemistry teacher has to make up convincing reasons for the class not to drink from.

Maybe my thinking has been wrong. I always thought you would need to supplement for some of the minerals you might be getting from the water. I could be totally wrong here then, will need to do more reading.

Any water you drink is already very much hypotonic relative to your bodily fluids. Your minerals mostly come from your food, not your water.

I’m no expert on biology (I’m a chemist), but I drank quite a bit of DI water in grad school because the tap water was so gross.

Also, heavy water (D2O) tastes sweet. And it also won’t kill you when consumed, contrary to urban legend (at least not in quantities you can reasonably afford).

> Any water you drink is already very much hypotonic relative to your bodily fluids.

True. The saline solution used for blood injections has 9000 ppm of dissolved solids. Whereas tap water above even ~200 ppm tastes disgusting to me.

> I drank quite a bit of DI water in grad school

Nice... but I wonder if it's considered food-grade, and if there are any non-ionic / non-polar impurities in it.

> Also, heavy water (D2O) tastes sweet.

I find that plain distilled water tastes sweet too. I can't afford heavy water, but this YouTuber did: https://www.youtube.com/watch?v=MXHVqId0MQc .

> it also won’t kill you when consumed

Deuterium oxide will kill you only after deuterium replaces a significant portion of all your body's hydrogen atoms, like maybe 50+%. https://www.youtube.com/watch?v=fyK6kPi8k78

Isn't reverse osmosis also filtering out minerals?

Yes, and as another poster pointed out my thinking that the importance of those minerals might be incorrect. I always thought you needed to supplement on top of distilled water.

For RO, a lot of the systems include a mineral cartridge.

It’s for taste. Distilled water tastes like crap. I don’t know the science behind it, but “good” water (eg coming from hetch hetchy) tastes amazing in comparison.

100% pure water sucks the salts and electrolytes out of your body though, so you'd need to dope it again with some minerals

It's not a legend, it's just chemistry.

It's mythological biochemistry. It does not reflect empirical evidence.

Exercising in hot weather requires drinking electrolyte water to avoid hyponatremia. Drinking large amounts of soft or distilled water (around 6 liters) can lead to death.

Water is hardly the worst of it. Most people I know microwave food in plastic on a regular basis, and have been doing so for decades.

If you wonder about the crazy rise in colon cancer, I'd say doing that plus keeping a cellphone next to your ass 16 hours a day would definitely be more than enough in an animal model.

Cell phones use a variety of wavelengths to communicate, topping out in the gigahertz range for things like Wifi. It's impossible for light in that range cannot to cause cancer. It's literally less possible for it to cause cancer than visible light. (Which is in the terahertz range)

I think you’re underestimating the myriad biological pathways which can all contribute to cancer, and also the unusual chemistry that can be induced when you tickle molecules at the right vibrational modes. There’s a whole body of literature describing so-called “microwave chemistry”, and these methods can greatly accelerate certain reactions – far more than simple heating with the same amount of energy can do.

With that said, I still put my cellphone in the front pocket every day, for most of the day.

Curse the time limit on editing. Impossible for it to cause cancer. Not "cannot to cause". Ugh. Why does HN have that dumb time limit anyways?

IDK about the cell phone radiation but given the trickle/torrent of bad indicators about our biology and plastic, my rule is no plastic near food, at least at home where I can control it. Definitely no freezing, heating, or microwaving plastic near food. Feels like one of the many accepted facets of space-age modern life that is too convenient to examine closely for most people, and I think it retrospect it will be viewed somewhat as we view lead in paint and fuel, asbestos in buildings, smoking in public, etc.

One thing I am sad about where I'm exposed to a lot of plastic but have little choice is that I wear a dental guard at night. This probably more than makes up for all the plastic food contamination I avoid in other ways. But after shattering three teeth from grinding in my sleep (waking up to a loud crack and an exposed nerve), I've decided it's the lesser of two evils.

Funny you say that because I have an appointment with my orthodontist this week to discuss whether or not I can have a permanent retainer so I can stop wearing the plastic one they gave me. If the answer is no, I’ll just forgo the retainer and deal with crooked teeth. I don’t want to sleep with plastic in my mouth every night.

We use a distiller now that is all stainless into a glass carafe. It has a small paper/charcoal filter that sits in a porcelain housing just before it drips. What is left over is gross. Not what it looks like, that is just minerals. But it smells like things I shouldn't be smelling. I'd like to build a glass only solar still to save all that power, and to avoid the high temps that I suspect are causing some reactions that release VOCs. Not all of which might be getting caught by the charcoal.

Do you have a link to the product? Interested in something similar.

https://www.amazon.com/s?k=water+distiller , for example https://www.amazon.com/CO-Z-Distiller-Stainless-Distilling-C... for $116 USD.

https://www.h2olabs.com/p-54-white-baked-enamel-model-300-wa...

It's become impossible to find a coffee maker where water doesn't come into contact with plastic. There used to be a pretty decent one: Gourmia GCM4900. It had some subtle design flaws, and only lasted 5 years. (If I can buy another one, I probably can somewhat mitigate that and make it last longer)

I use a moka pot. No plastic, no filters to replace. Great coffee. Takes a little bit longer but it's worth it.

This comes close to no plastic:

https://flairespresso.com/products/espresso-makers/flair-cla...

There's a silicon gasket, and they offer a stainless steel plunger upgrade. There is some plastic in the portafilter that coffee will touch (unless you run in bottomless mode).

The bigger problem with most espresso makers (but not the model I linked) is that they use brass for the heating block / boiler and that leaches lead into the water.

This matters less in coffee shops (where they use up the water in the boiler in a few hours or maybe a day), but a lot more at home (where you might only refill the boiler once a week or even once a month).

What do you use for freezing food if not plastic containers? Heating and microwaving, okay, I can work around the plastic containers/plates, but the freezer I have no idea how I'd do that. Especially that the freezer's casing is still plastic

Glass containers work fine and come in the same shapes as plastic containers do. They are heavier and take a little more space due to being thicker, but it's a small difference.

They do have plastic lids most often, but the lid doesn't have to touch food.

Yup, the IKEA one’s are more than good enough. And they’re borosilicate so you can even use them in the oven.

The plastic issue is also why I think people doing sous-vide are insane. You’re vacuum sealing meat into plastic and then giving it a nice long leeching in hot water. Sometimes with acidic foodstuffs!

Cheers, thanks for the info! So as long as the plastic does not touch the food, I'm basically good to go?

Aluminium trays, like that: https://www.emballagefute.com/img/plat-a-four-alu-sertissabl.... Yes, it’s non-reusable, pick your poison :/.

which study was that? anyone got the link? thanks!

Simply putting the comment text in Perplexity [1] leads to the following result:

https://www.pbs.org/newshour/science/scientists-find-about-a...

[1] https://www.perplexity.ai/

RO has some very easy to maintain, and user install options, which I've done.

( https://www.geappliances.com/ge/water-filtration-systems.htm )

However RO is not water efficient, in the sense that only a fraction of water run over the RO membrane system is filtered, and otherwise inbound water goes on into the drain. You can hear this happening, and it's documented by GE, for example, as how the systems work. That makes me wonder if there are other systems with the characteristic that a higher % of ingested water ends up filtered as well as RO can.

A permeate pump can typically reduce water waste in reverse osmosis systems by up to 80%. In general, permeate pumps can achieve a waste water reduction of around 50% to 80%. This means that for every gallon of purified water produced, only around 20% to 50% is wasted as reject water. This is achieved by utilizing the energy from the brine flow to enhance the pressure applied to the feed water, leading to increased permeate production and reduced reject water volume. Typically, these pumps range from $50 to $200 and they do not use electricity.

The elevated pressure allows for more effective filtration and higher water recovery rates. By boosting the pressure, permeate pumps facilitate a greater volume of water passing through the semi-permeable membrane, resulting in increased production of purified water (permeate) and reduced reject water (brine). The heightened pressure helps overcome osmotic pressure and allows for a more thorough extraction of purified water from the feed stream.

The domestic RO systems put pressure on the clean water output and don't have recovery systems for brine pressure? What? My only experience with RO systems are on sailboats, where a brine pressure recovery system is the only way to get the power down, and the water trickles into the tank under low pressure from where it is pumped out.

The linked system above just sends the unfiltered tap water down the drain. I have had two iterations of the GE system and it says so in the manual, for instance. I am not sure about other brands and their systems.

Most in-home systems sold today drain to waste without any attempt at recovery to keep manufacturing costs low.

They don't boost the feed pressure, just isolate the output permeate line from the back pressure of the storage tank. Instead of the membrane output pushing against the increasing pressure of tank as it fills (decreasing output) it produces into a void in pump body which the pump periodically pushes into the tank from spring mechanism wound by the output waste water.

They work pretty well to reduce waste but do add complexity to what is already a somewhat complicated device under the sink. They will also create bad TDS creep if used without an auto-shutoff valve installed in the RO.

It seems like it would be mostly irrelevant that it’s not efficient?

What percentage of residential water goes to drinking water? I think of all water use in aggregate, in many places it’s already 90% is agriculture and 10% residential. And of residential you probably waste more water in a single toilet flush than you drink in an entire day.

Anyone considered just sending the brine to the yard as gray water?

Premiere H2O has a system that dumped the water into the hot water line, similar to a hot water loop, but in reverse. There’s a lot of caveats with that arrangement (doesn’t really work with a tankless water heater, for example).

Wait, they push the waste/brine into the hot water line? Wouldn't that defeat the purpose of filtration?

I was thinking more of using it typical gray water usage like watering plants.

> Wait, they push the waste/brine into the hot water line? Wouldn't that defeat the purpose of filtration?

Hot water is for external use only.

You still absorb an astounding amount of chemicals through your skin.

... you’ve never used hot water to fill up, say, a pot of water for cooking?

it's gross. Don't do that.

I imagine despite the term brine it is still incredibly clean water

When you say brine is that in seawater desalination RO or are you using that to include non-seawater RO reject water?

You could definitely use it as gray water but if you are filtering for contaminants, that water would have a higher concentration and if you were pushing it out as gray water, would those areas of the yard have higher levels potentially of contaminants?

Yeah my dad has an RO system at their house but it goes to a special tap next to the main one that is used only for drinking water, due to the waste associated. Maybe it isn’t needed for hand washing, showers, etc as long as there are good standards at the water distribution facility.

Thats how I use it. In theory the waste could be used for irrigation or mixed into shower water but that requires more plumbing to deal with an external cost (in areas where water is limited).

Well, if you live somewhere with a municipal water supply, the water just gets recycled anyway. I suppose if you’re on septic it’s still going right back into the ground it came from.

Drinking water is probably such a small percent of overall water use that wasting even a multiple of it doesn’t amount to much anyway.

So filter away! I’ll worry about my r/o waste when people stop diverting rivers to grow almonds in the desert and not a second before.

A big issue is returning it to the ground doesn't mean it reenters the aquafer you might be drawing from if you're on a well system. It happens all over the place and especially in California, the aquafers aren't replenished well by ground water (and the extreme pumping causes the aquafer to compress permanently losing water capacity).

But again that’s entirely because of agricultural and industrial use. There’s plenty of water for homes, there’s not plenty of water for homes and mass farming in a desert.

This is the exact line of thought the people who use the water want to encourage. They want you to worry about your water use so you don’t worry about theirs.

I think the point is that we should not as a general rule recommend people do RO for their entire house. Toilets, showers, and washing machines don’t need RO water and if a lot of people did a whole home RO system we would start to see waste add up.

We live in a water supply area with water one order of magnitude harder than anywhere else in our county.

I'm putting an RO unit in our kitchen to serve drinking and dishwasher needs. Our dishwasher needs descaling after a couple of months of normal use. Other uses (shower, toilets) aren't impacted by our super-hard water, so no RO for the whole house, mainly because of the water waste you note.

Oh. Sure. That will always be so cumbersome we don't have to worry about it. That would be a huge RO system. They don't have a lot of throughput so you'd need a big storage tank or a very large set of filters and a pump I'd think. I'm not at all concerned whole home RO will every be common.

Only places I’ve seen it are places like China where people just don’t trust the water at all.

A friend of mine in Brazil had a whole home filtration system (not RO) that even had a UV sterilizer at the end!

I have an RO system, which seemed great until I realized the nicely filtered water runs through plastic tubing before coming out the faucet.

Maybe RO becoming part of the standard set of things you buy (washing machine, vacuum cleaner etc.) is the way.

It just seems really sad that society is moving away from "let's fix it for everyone" toward just giving up and saying "the only solution is everyone for themselves." Like, surely it would be much more efficient and cost-effective to improve water filtration at the municipal level rather than expecting everyone to buy and maintain their own individual filtration systems....

It might be more efficient (and effective) for the filtering to happen closest to where the water is drank. If it happens at the treatment plant, then you end up filtering lots of water that is used to water lawns, shower, etc. Only a small percentage is used for drinking.

I don't think it's good to have toxins on our lawns (where our pets roll around) or in our shower water either though?

This is correct. Pollution absorption though the shower is a thing

Agree, you also need chlorine in the water to treat the distribution system of pipes to your home. So you need to filter chlorine at point of use anyways.

I think this stems from the fact that the government takes years to do anything and mostly caters to special interests. If we could get them to actually take action on things then this kind of thing wouldn't be necessary but I feel like, more often than not, we're all left waiting on them to decide how to best make sure their industry/corporate friends aren't harmed before they decide to do what's best for the public.

Like the article says, Joe Biden is doing something about this, catering to all Americans. It's hard for me to see how you're offering a negative spin in light of this story. If you like this, vote in more people with the similar policies. Call your reps and potential reps and tell them you like this and you want to see more of this. Donate to their campaigns if you have the cash. This is how you give positive feedback. Don't vote for people who run on policies about deregulation.

This is the kind of annoying "more cynical than thou" comment which sounds insightful and meant to grasp at upvotes, but is really a self-fulfilling defeatist prophecy that leads us to a place nobody wants to be. We can and should expect better, but we also have to work for it instead of shrugging and giving up.

This is the kinf of annoying "holier than thou" comment which sounds insightful, but which is utterly divorced from the reality of our crumbling and dysfunctional government.

Just look at how Flint, MI was handled. It took years of nationwide outrage for the government to even admit that there was a problem.

Facts are that the US government is (now) intentionally and explicitly designed to remove all power from the people and give it to lobbyists and special interest groups. All levels of government explicitly ignore majority decisions and do whatever the fuck they want. Even votes barely matter when districts are gerrymandered so hard that all elections are predetermined. When that's not enough, we just go straight for bald faced voter suppression.

Things are not sunshine and roses. The US government is actively working against you.

Yes. If other readers are passionate about this, too, take note that a lot of issues like this, including water quality, are a policy choice. We should remember the politicians who are working to improve infrastructure that benefits us (in this case Joe Biden's administration) in the voting booth. We should not reward politicians who would have us fend for ourselves vs entities that already have every advantage.

Most of water I spend during the day is not drinking water.

I don't have a child, and don't know how much a child's uniform or excursion costs. Why not price it in dollars?

Maybe it would have been simpler if GP said it cost about 7-12 axolotls from Petco.

200-1000 plus installation, googling Home Depot.

Check out Waterdrop. The cartridges do just pop out and in, and it’s not zero install but it is very easy. If you can install a faucet you can install that.

I got over 99% reduction according to a cheap TDS meter at my condo in Phoenix with the 2 filter one. I can replace cartridges in seconds. I love that thing.

Zero install would probably suck as you’d have to fill tanks frequently (it rejects a good amount of water) and it would take up counter space but they do make em.

Honestly in most places you can buy the stuff for 25 cents a gallon from a machine, which is what I would do if I did not feel like installing

I've been a fan of the APEC countertop units; https://www.freedrinkingwater.com/products/reverse-osmosis-c...

Been using them for a few years, water tastes great.

That is a nice looking unit. I think as usual USA has more options! Might import something like this!

If it did cold water too would be awesome.

We are the best at having things to buy.

That countertop unit looks great.

Question - how do you deal with countertops that have storage tanks made out of plastic?

Are there no concerns with microplastics at all with these units? I know the plastic is not the Polypropylene stuff, but still.

the unit I have has no storage tank. The water comes out a tube that needs to fill something. We have a regular daily pitcher that gets filled several times through the day. I also fill up larger storage emergency water camping tanks. I guess those are made out of some kind of plastic.

I heard some RO filters could pass microplastics. I think it would be cool to see if any of that pics up in a microscope. What size particles are people zeroing in on exactly?

Zero install to me means “a renter can use it”. It could hijack your faucet outlet with a valve but allow your faucet to work anyway. This would require usually no tools or at worse a screwdriver to tighten a clip.

Well, the only real change that’s not easily reversible one might make when installing most of these units is if you don’t already have a hole to mount the faucet in. A renter definitely shouldn’t drill a hole in a countertop and most r/o units would require one. Any house built in the last few decades would probably have a built in dish soap dispenser you could pop out, but if not, no luck.

Other than that just basic hand tools are involved. I would have no problem installing one in a rental but I’m also comfortable with plumbing. It’s definitely a job that seems a lot more intimidating than it is.

> Any house built in the last few decades would probably have a built in dish soap dispenser you could pop out, but if not, no luck

Is this common? I’m not sure I’ve ever come across this idea but it sounds pretty convenient.

Not really sure why the informative sibling reply to my question is dead (and thus can't be replied to), but I wonder if that hole is what the air switch for my garbage disposal is mounted in...

I’ve found that landlords are usually completely fine if you tell them you’ll install it and they get to keep it when you move out.

Can be worthwhile depending on how long you plan to live in your apartment

RO doesn't really solve for filtering the water naturally inside of crops or meat. If you have a huge increase in groundwater pollution in a country, if your food supply isn't also in a closed system where only filtered water comes in, then you've only reduced your contaminant consumption not eliminated it.

Some RO systems like mine come with an alkalizing stage that adds Ca/K/Mg ions back: excellent flavor improvement to have it, too.

I feel like safe, clean water is the job of the municipal system that we pay so much for. Even the poors should have the same cleanliness as the middle class, but that's rather beside the point.

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