I've just noticed something about a lot of our PSKs that concerns me - the water bags included are not sized correctly for the kind of water treatment that is included.
For example, if you have repackaged some Potable Aqua and are planning to use a Gerber breast milk bag as your water container, you have a problem: Potable Aqua is formulated to work with one quart of water at a time, or 32 ounces. The Gerber bag holds 10 ounces at the most. You could use 1 Potable Aqua tablet, but that's still giving you way too much iodine for the amount of water you have.
If you're using Aquaclear or something similar, it calls for 1 tablet per liter (0.94 quarts, so they're roughly equal). If your water bag only holds 10-12 ounces, that is way more chlorine that you need.
I don't have any experience with Aquaclear tablets, but I know the Potable Aqua tablets are very small and would be almost impossible to divide without crumbling the whole thing to dust. I also don't know what health effects, if any, would result from using too high a concentration of water purification, but I'm sure that's a complication you don't need if you're already in a survival situation.

Yeah - I've been thinking about the same thing. For my larger kits, no problem: I've included a Camelback bag, roasting bags for backup, and so on.

In my PSK, I ended up wrapping everything in a 1-quart ziploc bag, which besides keeping my "modules" further protected and together, provides a mixer bag for the water purification. I have two Gerber bags in the kit that seem like they'd be sturdier and easier to carry in pockets, and which I'd fill from the ziploc bag.

Barring that, I figured I'd cut or chop up a tablet and eyeball a pinch equivalent to 1/3 of the tablet and dump it into the Gerber bag with untreated water. Even half a tablet in each of the two Gerber bags is probably fine. Might not taste great, but wouldn't hurt anyone.

Options; prepare the tabs by carefull division before packing. You can scribe a tablet carefully with a small blade to form a fracture line. a messier alternative would be to prepowder the whole supply and carry a tiny measuring device. Another alternative is to carry a larger bag on your person, such as a ziplock in one quart size.

And there's the goldfish bag solution. Plastic bags of sturdy millage that are about a quart but fold up really small. (About as small as a roasting bag.)

I have a case of a thousand, and will still send ten to anyone for the price of a SASE. Email me for the mailing address.

Bear

Your response highlights my main concern - I noticed this problem in some of the commercial kits, including some of those reviewed on ETS. You and I have thought this problem through, but what about the people who just buy the kit and figure they're set? It may not kill them to overdose on iodine or chlorine, but ... if you're using the kit, you're usually not in a good situation to begin with. I hope the kit makers will think this issue through a little better before just tossing any old size of plastic bag in and figuring that they're done.

i use 2 1L zip-loc bags in mine PSK, in mine opinion the best solution.

From a practical perspective for short term use it just isn't an issue. I have spoken with all the manufacturers and a number of independent authorities and all have said don't worry about it. Obviously, taste may be an issue for some, but there are no negative health concerns for short term use. Use those levels for a month or two and you might possible have some issues, maybe. Need to find something else to fret about. <img src="images/graemlins/smile.gif" alt="" />

Doug,

Have you checked with any medical doctors about this? It seems to me that same chlorine or iodine that will kill bacteria and microorganisms in the water will do the same thing in your digestive tract. I would think that this could lead to stomach cramps, gas, or diarrhea. Speaking of which, is everyone packing Pepto Bismol and Immodium in their first aid kits and T.P. in their survival kits?

Some of the specialists I have discussed this with are docs as well as being specialists in water treatment. Your assumption is not correct. Chlorine and chlorinated compounds are the most widely used disinfectant in municipal water systems the world over. Iodine based water disinfection has been used globally for water disinfection for decades. There is tons of information on this topic on the Web or at your local library and most of the authoritative wilderness medical texts also cover the subject.

Doug,

I agree with you about chlorine and iodine being used to disinfect water, but surely there are concentrations beyond which the water becomes unsafe to drink.

Potable Aqua, for example, has a dosage of 2 tablets per quart of water, or 1 tablet per pint (sandwich bag amount). If you were to try to disinfect half a pint with a single tablet, you would have twice the required concentration of iodine. Is there not a point at which the concentration becomes toxic, or affects your digestive system as I described earlier?

There are no doubt concentrations beyond which some sort of health issues manifest themselves, but apparently not till you reach far higher concentrations than we are talking about here according to those with which I have consulted. You can die from too much pure water as well. <img src="images/graemlins/grin.gif" alt="" /> This is simply what I have discovered in my research on this subject over the years and the answers I received I find satisfactory for my purposes WRT survival use. I have used many of these products in such manner without adverse effect. YMMV and far be it from me to try and convince you otherwise. You can always use alternate methods, larger containers or cut the tablets or amounts to maintain the original ratios, or die of dehydration if you so choose. <img src="images/graemlins/crazy.gif" alt="" />

This where that condom comes into its own. It might not be as resiliant as some plastic bags, but it will hold the amount of water!

Well, this discussion has answered some of my concerns, which is why I asked the question in the first place. Again, this is one of the major highlights of the Survival Forum, this exchange of information, opinions, etc.

Maggot and Tackdriver303,

The concerns you both have about Potable Aqua iodine tablets are not an issue for me or any other experienced climber or hiker, even if you ingest 2 or 3 ounces of pure iodine crystals the most that could happen to you is that you could possible get sick and possible die.

But if you but if you eat something afterwards you might not,
but if you are allergic to iodine you probably will.

Discuss it with your Doctor if you doubt the validity of the information.

The Potable Aqua iodine tablets are save even in the amounts you outlined.

What Doug is telling you is the best information available on the subject!!!!!!! I have been hiking and climbing for 20 years, this site has first class information.

Hi Maggot,
Interesting discussion. Thanks for bringing it up.
For those who still may have reservations regarding this matter...
My first thought is to have three breast milk bags. Dissolve one Potable Aqua tablet in one, then divide the contents evenly into the three and fill them all. This approximates the correct dilution. If you don't have three breast milk bags, dissolve one tablet into one bag, pour two-thirds of it out and fill it full again. It's wasteful, but better if you (or someone else) was really concerned about concentration.
My second thought is that I really need to go try to split a Potable Aqua tablet into parts with my Micra to see how hard it really is.
My third thought is that David's fish bags (or oven bags) might be the better solution for kits that have room for them.
Stay safe,
J.T.

Let me throw in my 2 cents for what it is worth. Our lab is responsible for monitoring the health status of research animals. One common practice is to treat water with either chorine or acid to reduce microbiological contamination. Water is treated with chlorine to achieve 8-12 ppm of available chorine. At these levels the water does have bacterial static effects on intestinal organisms. Pseudomonas aruginosa is one indicator organism for which we monitor, being both an opportunistic pathogen as well a common fecal contaminate. Chorine levels are affected by light, organic materials (bedding, feces, etc.) and dissipation. Generally within 24 hrs, original chlorine levels of 8-12ppm are below 0.5ppm. When monitoring for Pseudomonas aruginosa levels (from feces), during the first 24 hrs, levels of the organism are below detectable levels, as the available chlorine levels are decreased (24hrs+), there is a rise in the detectable levels in Pseudomonas aeruginosa isolated from feces. It is general practice to change chlorinated water bottles every 2-3 days. Acidified water, reduced to a pH of around 3.0-4.0 is stable from both a chemical and bacterial static point of view for 5-7 days. The water for both mythologies is generally not palatable to humans. Pete