#24: Water Filtration – Prevents Mutation

The Question

ben Says:
March 1st, 2005 at 11:21 am

The water in the water cooler at work is from Nestle. It says that it’s been filtered through a “Reverse Osmosis” process. What does that mean, to me the consumer, and is this better than other filter methods? Should I prefer it over Brita filtered water?

The Answer

I can state this definitively: Reverse Osmosis is better than most other filtration methods.

In this answer, I will break down the most common water filtration methods, describing each, in order to prove that Reverse Osmosis filtration is better than the rest. The most common filtration methods are:

– Distillation
– Ion Exchange
– Carbon Adsorption
– Filtration
– Ultrafiltration
– Reverse Osmosis

Distillation is when you take your tainted water and evaporate it, directing the vapor towards some sort of condenser, where the water collects and drips into your drinking bucket (I assume you drink out of a bucket). This is okay, if you’ve got time to wait for your water to evaporate, condense, and drip, and you happen to have a really powerful source of energy to point at the water in order to make it evaporate or boil (like a death ray). It’s also okay if you want to drink bug killer, since that stays with the water when it evaporates.

Ion Exchange:
This is when you have a bucket of salt beads to push your water through, and your water has a lot of metal in it (like iron and manganese). What happens is that the dissolved metal ions in the water stick to the beads of salt and (somewhat like bartering) exchange sodium ions for your water’s more valuable iron or manganese. The beads will then take the metals and trade it in for a brand new moped, while you are left with “soft” water. The problem with this method is that it doesn’t remove chunks of badness from your water (this is called “particulates” by the faint of heart). Also, bacteria likes to live on the beads, which makes your water nasty.

Carbon Adsorption:
This is what a Brita does. Basically, your water flows through a block of “activated” carbon. “Activated” means that the carbon has been charged up by your death ray and that you have inserted the “Key of Horus” into it. It can also mean that the block of carbon was heat-treated in such a way that it has lots of tiny holes. These holes function as “jail cells” from which bad things cannot escape. These jail cells trap dissolved organics and chlorine effectively. This makes your water taste good, and it provides some measure of good feeling since you know that most of the bad organic stuff is now in jail. However, like any jail, the cells eventually fill up and you have to change your filter. This method also does not guarantee the removal of lead or coliforms from your water.

Filtration is when you force your water through something with very small holes (like one of those strainers that I sometimes use to create pulp-free lemonade). This is good for removing anything in suspension, but bad for removing anything that has been dissolved. Enough said.

Like filtration, but its taking the volume up to 11. You actually filter out molecules with one of these. Still not good for getting rid of stuff that’s dissolved in the water.

Reverse Osmosis:
This is the king of water purification methods. As you are most likely aware, regular osmosis occurs when two solutions of different concentrations are place next to each other, with a semi-permeable membrane between them. Water will leak through the membrane until the concentrations are equalized (because water is totally controlled by peer pressure and wants to be just like everyone else). Reverse osmosis occurs when you apply hydraulic pressure to the solution, forcing the pure water to go through the membrane the other way, into your pure water collection place. Practically nothing gets through the Reverse Osmosis membrane. But, because the membrane is so fine, it takes a long time for the pure water to come out. Luckily, if you are drinking water that has already been purified via Reverse Osmosis, you don’t have to wait for anything – it’s already there. Reverse osmosis is especially good for removing any dissolved radioactives, like plutonium. So you are less likely to mutate.

8 thoughts on “#24: Water Filtration – Prevents Mutation

  • 5/23/2005 at 4:09 am

    I was sad not to see an ultraviolot radiation method of filtration described. We use it mostly on ponds, and is totally impractical for small, personal use. However, it is still a major filtering method.

  • 5/23/2005 at 7:18 am

    Once again, your clever well researched answer has left me thirsty for more.

    THIRSTY. get it. ha ha ha.

  • 5/23/2005 at 8:12 am

    I disagree with your use of the word filtration. Filtration in my mind implies you are using some sort of filteror something. Distillation is a process and doesn’t in the most general sense involve filters, thusly I do not consider it a filtration process. Instead of saying The most common filtration methods are:” I think it would be more accurate to say “these are the most common water purification methods” b/c only a few of the methods listed are filtration, but all are purifcation processes. Just my two cents!

  • 5/23/2005 at 9:51 am

    Why does Nestle make water? Aren’t they all about chocolate chips?

  • 5/23/2005 at 10:04 am

    Bravo, shaun, bravo.

    And I’m with Jill on that one too, I always want the water to taste like chocolate, but i gues all the chocolate particles are still on the wrong side of the semi-permeable membrane!

    And, as a follow up, do you think nestle uses the water that power plants used for reactor moderation and then filter out the radiation? Would drinking heavy water kill me?

  • 5/23/2005 at 12:24 pm

    I enjoyed your “Key of Horus” comment. That made the whole description feasible.

  • 5/23/2005 at 12:49 pm

    To Mykal:

    Good catch! I should indeed have said “these are the most common water purification methods”. I will not correct it because then it would look like your comment is silly. We don’t want that.

    To Becky:

    Good catch! My research did indeed show ultraviolet as a water purification method. I chose not to include it because I knew you would be reading the post and wanted to encourage your input. Really. That’s why I didn’t include it. What, you don’t believe me? :-)

    To Jill:

    Good question! It turns out that Nestle has been in the water business since 1969, and “is established in 130 countries and markets about 70 different brands” and the water business “now represents 9%” of Nestle’s sales. (Source: See the Nestle web site for full details)

    To Ben: I am sure that Nestle does not use heavy water as a source for its bottled liquid goodness. Sorry, still no mutation in the works.

    To Kurt: I aim to please.

  • 5/23/2005 at 2:09 pm

    But it would lend to such awesome marketing!

    “D2O… the d is for double delicious!”


Leave a Reply

Your email address will not be published. Required fields are marked *