Water purification tabs as a disinfectant?

Posted by: Tirec

Water purification tabs as a disinfectant? - 10/02/07 09:45 PM

In my kits I carry Potable Aqua. According to the manufacturer, it's "a proprietary compound called TGHP (Tetraglycine Hydroperiodide). Each tablet contains 20 milligrams of TGHP, which liberates 8 milligrams (ppm) of titratable iodine." The recommend 2 tablets per quart or liter when disinfecting water.

My questions for the chemist/medical types are, when mixed with water, can this be used for other purposes like a tincture of iodine in disinfecting wounds? If so, how much water should it be mixed with for disinfecting as opposed to water purification?

If able, this could eliminate one thing in the kit, since multiple uses of kit items is desirable.

Thoughts?
Thanks
Posted by: eric_2003

Re: Water purification tabs as a disinfectant? - 10/02/07 10:06 PM

To get a 1% iodine solution, you'd need 10 mg of iodine per ml. So that's 100 mg for a 10 ml disinfection solution.

Which is about 10 tablets into 10 mls to get just under 1% iodine, but perhaps 5 tablets could be used to get a more dilute solution that is less irritating.

I don't know if that many tablets would dissolve into the small amount of water, but I take the reverse approach. I EDC a small vial of poviodine for wound disinfection and water purification, even though poviodine doesn't allow for very accurate calculation of iodine release, as the iodine is stuck to a polymer. I also carry a vial of tincture of iodine (one that has ethanol as a diluent) in my BOB as well.

There is lots of new research with chlorine dioxide being used as a disinfectant, but I haven't had the chance to look at the concentrations used on wounds yet.
Posted by: JIM

Re: Water purification tabs as a disinfectant? - 10/03/07 01:38 PM

You can just use the tabs as you would do for drinking water:
2 Potable Aqua tabs per 1l of water (1 tab per 1l for the other brands) and use it for the irrigation (flushing)of wounds if your water-supply is contaminated/unrelyable.
I don't think you can use it to make a antiseptic for wounds though. Just for the water..
Posted by: ironraven

Re: Water purification tabs as a disinfectant? - 10/04/07 04:44 AM

I seem to recall reading that it was one PA tablet dissolved in an ounce of water. But this was quite a while ago, and the book had some *cough* interesting procedures in it.

For what it is worth. I have no idea what concentration of iodine that would be, or even if it is the right kind of iodine solution.
Posted by: Leigh_Ratcliffe

Re: Water purification tabs as a disinfectant? - 10/04/07 07:47 PM

The issue here is contact time. If your trying to sterilise a wound you might do better to put a sterile dressing over it and then slowly soak the dressing. It should retain enough iodine to have an effect.

Of course, he who does not carry a decent antiseptic in his kit is begging for trouble.
Posted by: Arney

Re: Water purification tabs as a disinfectant? - 10/04/07 08:56 PM

Originally Posted By: eric_2003
To get a 1% iodine solution, you'd need 10 mg of iodine per ml. So that's 100 mg for a 10 ml disinfection solution.

It's been ages since I've taken general chem, but Eric, are you sure of these concentration calculations?

I was doing a little searching on Google and I found this webpage. According to this page, one tablet in a quart/liter canteen gives you an approximately 5% solution. That should be a decent antiseptic strength without the iodine becoming too irritating to the wound.
Posted by: eric_2003

Re: Water purification tabs as a disinfectant? - 10/04/07 11:56 PM

From the web-page quoted above:

One Portable Aqua tablet per quart of water gives you a concentration of 5.3mg/liter.

Using that concentration:

5.3 mg/liter = 5.3 mg/1000 ml = 0.0053 mg/ml

Considering that 10 mg/ml = 1%,

0.0053 mg/ml divided by 10mg/ml gives you 0.00053 %

That last percentage is great for drinking but not for disinfection.

For the response to the original question, as long as the quoted amount of iodine per tablet was correct, the concentrations should be right too...

I still like carrying a vial of free iodine better. Just look for 1 or 2% iodine tincture that uses ethanol, not isopropryl alcohol as the diluent.

Eric
Posted by: asfried1

Re: Water purification tabs as a disinfectant? - 10/06/07 03:47 AM

Originally Posted By: Tirec
In my kits I carry Potable Aqua. According to the manufacturer, it's "a proprietary compound called TGHP (Tetraglycine Hydroperiodide). Each tablet contains 20 milligrams of TGHP, which liberates 8 milligrams (ppm) of titratable iodine." The recommend 2 tablets per quart or liter when disinfecting water.

My questions for the chemist/medical types are, when mixed with water, can this be used for other purposes like a tincture of iodine in disinfecting wounds? If so, how much water should it be mixed with for disinfecting as opposed to water purification?

If able, this could eliminate one thing in the kit, since multiple uses of kit items is desirable.

Thoughts?
Thanks


In a word, "yes". Per the consensus of the wilderness medical community, any water that is safe to drink is appropriate for wound cleansing. As far as how to use your disinfectant tabs, use the exact same formula as you would to make your drinking water safe. There is lots of data to support the concept that wound cleansing does not require sterile water - just drinkably clean water.
Posted by: eric_2003

Re: Water purification tabs as a disinfectant? - 10/06/07 12:59 PM

Water that is safe to drink usually is no problem at all for irrigating superficial wounds. As for disinfection though, separate from cleaning, you'd need something a bit stronger.
Posted by: asfried1

Re: Water purification tabs as a disinfectant? - 10/11/07 02:31 PM

Originally Posted By: eric_2003
Water that is safe to drink usually is no problem at all for irrigating superficial wounds. As for disinfection though, separate from cleaning, you'd need something a bit stronger.


No medical support for that. There is some pretty good evidence that "stronger" stuff will cause tissue injury and result in an increase in infection rates. Good data from major trauma centers speaks to the fact that tap water or safe drinking water is appropriate (even better) than anything else for any wound whatsoever - even deep wounds that require extensive closure or open fractures.

A good reference text for this stuff is Wilderness Medicine by Paul Auerbach (one of the founding fathers of Wilderness Medicine as a discipline):

http://www.amazon.com/Wilderness-Medicin...8247853-3328460
Posted by: JCWohlschlag

Re: Water purification tabs as a disinfectant? - 10/11/07 03:13 PM

I think we need to be careful about the terms we are using. “Disinfection” usually refers to the killing of microbes on or in an inanimate object. “Antiseptic” usually refers to the killing of microbes on skin (unless you specify something like “skin disinfectant”).

While “disinfectants” and “antiseptics” are the same chemical in many cases, “disinfectants” are a much stronger concentration since safety of living tissue is usually not a concern.

For cleaning an open wound, regular (safe, drinkable) water is recommended for pressure irrigation. It has been shown to do just as effective a job while not causing tissue damage, stunting healing, or promoting scar tissue. You can use water purification products to create or ensure safe irrigation water, but remember that your objective is to kill the germs in the water, not to kill the germs in the wound. Don’t go crazy with the chemicals. Irrigation with sufficient pressure is all you need to clean the wound.
Posted by: Anonymous

Re: Water purification tabs as a disinfectant? - 10/11/07 03:17 PM

I've always gone with the belief that the best thing to clean out wounds to prevent or calm an infection is a salt water solution. I have an MSR MIOX Pen so I always have a supply of salt in addition to purification tablets.
Posted by: asfried1

Re: Water purification tabs as a disinfectant? - 10/11/07 09:59 PM

Originally Posted By: Hacksaw
I've always gone with the belief that the best thing to clean out wounds to prevent or calm an infection is a salt water solution. I have an MSR MIOX Pen so I always have a supply of salt in addition to purification tablets.


Again, the studies that have been done support the use of plain old drinkable water. There is no advantage to a salt solution - even a completely sterile normal saline irrigation solution. In fact, the evidence suggests that the use of tap water for wound irrigation may be associated with fewer infections than sterile saline.
Posted by: eric_2003

Re: Water purification tabs as a disinfectant? - 10/12/07 02:51 AM

I am swapping out my benzalkonium chloride wipes in the first aid kit for chlorhexidine wipes. Chlorhexidine gives a more persistent disinfection (whoops - antisepsis) that would be beneficial in preventing infection. Asfried1 is right on how tap water is usually adequate for irrigation, but if my FAK had to be used in a non-urban, or a setting without the comforts of home (and hygiene), then persistent activity against microbials would be useful since you can't count on 1) a clean environment, 2) your barrier dressing holding up.
J Hosp Infect 1984 showed that chlorhexidine prevented non-infected wounds from becoming infected, better than saline - this is useful in non-urban settings.

Regarding the miox, also electrolysed oxidized water was shown to be markedly superior to water or saline in serious wounds such as burns. It was superior in preventing local and systemic infection. I have no idea how the miox unit would convert in terms of getting the right concentration, but I remember I investigated this a while back and the marketing rep had told me a solution of 2.5% was made (standardized to chlorine though, and it didn't take into account the other more potent oxidants that miox generates).

Eric
Posted by: Anonymous

Re: Water purification tabs as a disinfectant? - 10/12/07 05:08 AM

I did some digging and found an amazing study.

The study compares just about every irrigation solution and techniques...even the pressure of the irrigation...the results surprised me.

The article ends with some great advice on what to use, when, and how.