MSR Aquatabs Water Purification Tablets

I've not used this MSR product, but I chatted with an REI employee about this today. The Aquatabs generate 2.6 ppm of CHLORINE per tab (in 2 liters of water). Both Katadyne's MicroPur and Potable Aqua's Chlorine Dioxide tablets generate 4 ppm of CHLORINE DIOXIDE (per 1 liter). The CDC feels that chlorine dioxide is a bit more effective than chlorine at neutralizing spores (both will quickly wipe out viruses and bacteria). Chemically, these are two different things.

The REI buddy sent out a radio message to his colleagues throughout the store, asking them why REI chose to no longer carry chlorine dioxide, and nobody knew. We do know that Katadyne had production problems last spring when they relocated to a new facility. Whether or not they have now resumed production is not known. Apparently REI had carried the Potable Aqua version of chlorine dioxide this summer, but they no longer do so.

I think I'll do a google to see if the CDC had determined chlorine dioxide was evil while I was up in Yellowstone being bear/bison bait.

Edit: I can't spell
Edit: Bob is right, the MSR tabs yield 2.6 ppm of chlorine not 2.4 ppm; I can't do numbers either, but luckily I have Bob covering me this week.

Coincidentally, I just returned from a trip to the REI store to buy some water treatment tablets of some sort. I had in my mind that I was looking for Chlorine Dioxide, because I had used the two-part liquid form. I purchased the only thing that they had, which was MSR Aquatabs. Its label says that one tablet will produce a 2.6ppm available Chlorine solution when dissolved in two quarts of water.

Like you say, Chlorine is different from Chlorine Dioxide.

Geez, if I knew that all I was getting was Chlorine, I could have just packed up some household bleach. It would have cost about 2% as much.

–B.G.–

I didn't notice that one MRS tab treats TWO liters of water. I did an edit to my previous post to indicate that (after checking out the product on REI's web page). Seems kind of inconvenient, if you only need a single liter treated while hiking. Bob, are those tablets scored, so that you can break them in half for a single liter (but then what do you do with the extra half)?

Gary, the MSR tablets are quite different from MRS.

One package holds 30 tablets, arranged into three foil strips of 10 tablets each. I have not unsealed any of the foil strips, but I tried to shine a bright light through the foil to see what they held. The tablets appear to be teeny tiny pills, each about 5mm across. The expiration date is about five years out.

–B.G.–

MSR, MRS, SMR, SRM, RMS, RSM? They are all the same to an apparent dyslexic like me…

Also, Clorox is actually sodium hypochlorite, which is yet again another chemical, which is different than chlorine or chlorine dioxide.

This all gets pretty confusing, no? They all kill cooties, but some are more effective than others. Pick your poison, which in fact they all kind of are, but not very significant in the doses we use.

"Clorox is actually sodium hypochlorite"

Yes, but it makes chlorine when in solution, just like other stuff.

Chlorine can be an effective water treatment for some kinds of bugs, but not for everything.

Pick your poison, huh? It seems that chlorine gas was used for that in WWI.

–B.G.–

Like others have mentioned, it seems that chlorine dioxide tablets have been pulled from most shelves! (Still available on eBay and other sources if you search hard for it.) Haven't been able to discover why. Last year I used Aqua Mira chlorine dioxide tabs, this year they're unavailable in any brick-mortar store I look. Aqua Mira tabs have been suspiciously "out of stock" for some time from the mfgr's own website. Purchased the MSR Sodium Dichloroisocyanurate tabs instead. Notice the package gives TWO different potency mixes, one for water with organic contamination (6.5 ppm) and one without (at 2.6 ppm). It appears that 1 tab per liter splits the difference between the two concentrations (1 tab per .75 liter and 1 tab per 1.9 liter) somewhat.

It appears that chlorine is less desirable than chlorine dioxide (CD) in a number of different ways: "It is more effective as a disinfectant than chlorine in most circumstances against water borne pathogenic microbes such as viruses,[20] bacteria and protozoa – including the cysts of Giardia and the oocysts of Cryptosporidium." (Wikipedia.) Why CD is gone, I don't know. Sure, it's deadly in concentrated form–the CDC has known that since 1958 when they killed rats by repeatedly exposing them to 10 ppm of CD. But that's very old news.

Remember: Sola dosis facit venenum — it's the dose that makes the poison. Pretty much anything is poisonous if you ingest too much of it.

All I can find is a 2010 warning by the FDA against a homeopathic remedy that created large amounts of CD. Why it has been dropped by Amazon, Sport Chalet, REI, and even the manufacturer, I have no idea. In situations like this, one suspects some fool killed himself with an overdose of CD and the nanny state now punishes everyone.

I'll look for the thread, but someone mentioned somewhere else that they talked to a distributor and found out that all CD is produced in a factory in Germany. That factory had a fire which means no more cd worldwide until the new factory is up and running. Apparently the new factory has been built as is being checked out. People expect CD back on the shelve in Sept.

*edit: found it: http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=78573

second post by Gary Dunkel.

I was getting tired of mixing Aquamira solution, went looking for the CD tabs and didn't find them anywhere in the stores. Ended up with Aquatabs, they are pain to split into half if I want to treat water sitting in a Gatorade bottle. I also read they can't kill Cryptospordium, Now I am thinking about going back to Aquamira drops.

Incidentally, yesterday I was walking through a small mom&pop outdoor equipment store, and I spotted this item:

Coleman Chlorine Dioxide Water Purification Tablets, 20 tablets, $12. Each tablet treats one quart of raw water. However, the recommended contact time is four hours.

The package says that it generates 4ppm of chlorine dioxide, and that it kills giardia cysts, crypto, bacteria, and everything else.

–B.G.–

You should jump on those, Bob, as they're likely the last of those German-made ClO2 tablets that we'll see for awhile.

I don't think anybody wants to wait for 4 full hours to drink water.

Gary, I would not have the text off the packaging unless I had it sitting here right beside my computer.

So, I have a package of the chlorine tablets that I got a couple of weeks ago, and then I have a package of the chlorine dioxide tablets from yesterday. Then I have new bottle of iodine pills. Finally I have a small vial of bleach, enough to treat a gallon or so of water.

I guess I am stocked up for now.

–B.G.–

"I don't think anybody wants to wait for 4 full hours to drink water."

Right. It kind of depends on where you are, how hot and dry you are, and what kinds of bugs you are trying to kill.

In other words, with some chemicals you can increase the concentration which decreases the time to kill the toughest bugs.

Often times I will set up a 2L Platypus of water with a very low dosage of chemicals, and then leave it overnight.

–B.G.–

If these companies are using the same chemical why does Aquamira tells to leave the tablet for 30 mins and Coleman suggests 4 hr treatment time.

It kind of depends on where you are, how hot and dry you are, and what kinds of bugs you are trying to kill. It depends on the chemical concentration in the water and how far out on a limb the marketing department of the vendor wants to go.

–B.G.–

hmmm

if you have to wait 4 hours, then you have to carry an extra 1/2 liter of water which weighs 1 pound

if you used a Squeeze, that only weighs 3 ounces

I have Sawyer Squeeze but for some reason, I find its not there either on the ease of use or a full fledged water pump kind filter, also store the wet plastic bag, making sure to drain all the water from the filter makes it very unattractive option to me. I ended up using Aquamira drops and now MSR tabs.

"…makes it very unattractive option to me…"

use soda or water bottle rather than collapsable bag.

after you remove Squeeze, shake it out vigorously. Swing it at arms length about 10 times. Then put in plastic bag to contain the few remaining drips.

or just leave it on bottle and put into pocket on pack.

of course nothing works for everyone. There are some techniques to figure out to make it more "attractive"

From what I remember, for any (edit: probably not for aquatabs) of these tabs it's 4 hours to kill crypto and 30 minutes if you only care about the other stuff. The brand is largely irrelevant and the maker will list whichever of the two times they want, with appropriate disclaimers if they choose the shorter.

wow that's one tough germ.

MSR aqua tabs don't kill Crypto, any idea where these nasty tough germs are found? only place I remember reading that Crypto was present was Olympic national park in Washington, but I didn't know I had to wait 4 hrs to kill them, I waited 30 mins and drank the water ;-)

30 minutes will kill most bacteria and parasites with the tabs. It takes 4 hours to kill Cryptosporidium, some directions account for this.

Looks like Aquatabs are Sodium Dichloroisocyanurate, which releases plain chlorine as opposed to chlorine dioxide. Chlorine is much less effective than chlorine dioxide, so I'd only consider the "4 hour" time as applying to the chlorine dioxide tabs.

"Chlorine is much less effective than chlorine dioxide, so I'd only consider the "4 hour" time as applying to the chlorine dioxide tabs."

Is that what you meant?

If Chlorine Dioxide contact time is 4 hours, and if Chlorine is less effective, then its contact time must be even longer. This conflicts with the labels.

–B.G.–