Picture of How To Purify Water Using Iodine Tincture
When you're in the wilderness, you need clean water to drink -- but water sources in the wilderness can carry bacteria such as giardia. You don't want giardia, trust me, and trying to carry a few jugs of Poland Spring would be extremely heavy and inefficient. Luckily, there are a number of ways to purify water, and one of the simplest, cheapest, and most effective ways is to use iodine tincture.

Step 1: Supplies

Picture of Supplies
To complete this task, you'll need the following:

--Water bottle: A Nalgene (what I use here) or a metal water bottle will work best, but all you really need is any container that will hold water.

--Iodine Tincture Solution: You want Iodine Tincture with 2% Iodine and about 47% alcohol. Bottles of this solution should be available at your local drugstore and a 2 oz. bottle is usually $3 or less.

--An eyedropper: Counting the number of drops is the easiest way to keep track of how much you're using.

--A good water source: This can be a lake, a river, a stream, etc. If you have a choice of water sources, consider these two tips:

Clear water is better than cloudy water.
Flowing water is better than still water.

Remember, though, that even if the water looks extremely pure and clean, it should still be purified before drinking. Looks can be deceiving!
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RodyK1 hour ago

Iodine loses his quality when used with aluminium pots or bottles, it reacts with direct contact with aluminium. Boilling is another option, just get a rolling boil. Active coal only removes certain chemicals (low and medium complex chemicals) no virusses or bacteria. Home made active coal is not exactly the same as from a manuafacturer. Active carbon is made from treated coconut shells. (gives the best result). Be careful for iodine intolerance (pregnant women).

Effective water purification could also be done by using dried Moringa seeds if available. http://miracletrees.org/moringa_water_purification...

medbnet10 hours ago

Read up on how to make activated charcoal. If you burn hardwoods in your fireplace like oak or ash, you can shift through ashes after everything as has cooled down and you will probably find little pebble sized pieces of charcoal that can easily be made into activated charcoal (see y-o-u toob). I have 2 large coffe cans full of the aforementioned from last winter. Along with some sand and some stones and a piece off fabric you can "purify" quite a bit of water. Also, you can add 7 drops of bleach per gallon.

I save all of our fireplace ash. It's a great moss killer. Also, if it is hardwood ash, you can use it to make soap, and use it for many other "Little House on the Prairie" apps.

How many drops per gallon of Lugol's should you use?

Lastly, always boil afterwards if possible.

I was a paramedic when being a paramedic was a new thing. One of the top items in a first aid kit used to be activated charcoal. Whenever a kid ate a bunch of pills, or the depressed housewife tossed back a pile of pills, we would first give them ipecac to make them vomit. Then we would give them activated charcoal mixed with a fast acting liquid laxative. That would assure that most of the poison was absorbed and evacuated from the body out of one hole or another. Anyway, my dog ate about 20-25 toadstools yesterday. Nature took it's own course, and she vomited 6 times, making sure all of her stomach contents were totally evacuated. I went over to Walgreens to get some activated charcoal, to make sure everything was absorbed, and they don't even sell it anymore! I think it is a good thing to have in a first aid kit so it is still there if someone - or their pet - ingests something poisonous. So being able to make your own might be the only way to get some.

Activated charcoal and sorbitol (Actidose) is still quite popular in emergency medicine for toxic ingestions of all descriptions. The combo isn't available OTC, but activated charcoal in capsule form is. Look for it in the supplements aisle of your more naturopath-inclined health food stores and pharmacies.

As for using activated charcoal as a water filtering tool, keep in mind that activated charcoal is a chemical adsorbent agent - it'll bind out lots of small molecules (halogens and compounds thereof, some toxic aromatic compounds, etc), but it doesn't do anything for toxic alcohols, heavier hydrocarbons or for microbiological hazards. It's most useful as an adjunct for taste improvement after sanitization with the free halogen of your choice (chlorine, iodine...), and only if you can ensure that your water source isn't contaminated with petroleum products or whatnot.

Get activated charcoal from the filter section of the fish filter section of the pet section of your local store.

Roger That!

Iodine and iodine tablets are effective but I've never liked the taste. I use to use it a lot when I went camping as a kid before portable filters were affordable. Besides the taste, the other big drawback (which is kinda cool) is that if you boil pasta in iodine water, it will turn purple! It doesn't affect the taste but purple mac'n cheese takes a bit of getting use to.

Iodine forms a complex with starch. In your case, the iodide is formed from the iodine diatomic molecule itself. I'm guessing the purple was quite pale?


Yeah.... that's exactly right. We had a outdoor club in high school where we did a lot of camping and other outdoor activities. That was one of our "ah ha!" moments when we learned about that reaction in chemistry class and put together why our pasta always turned purple on our camping trips when we used treated water.
StephenS177 hours ago

iodine crystals being one of the main ingredients in methamphetamines, you might find it harder to find these days.

mellowdog7 hours ago

mint works too xxx

namora8 hours ago

Iodine is sold as an antibacterial for beer making but not since I was in the Boy Scouts sixty years ago have I heard of using it for water purification. I still remember my response to the taste.

There is a cornucopia of purifiers on the market today that seem to be a pretty good investment. DIY only makes sense when the product works well.

smilesfromnowhere made it!8 hours ago

I've used an MSR water filter for a couple of decades now and still haven't had to change the filter (200 gallon limit). The bottom of the filter unit screws right on to a Nalgene bottle for convenience. This filter will provide clean, decent tasting water from a swamp or mud puddle if necessary, which to me justifies the extra weight and expense over just iodine, which always tastes funky.

MSR Miniworks Water Purifier.jpg
scook98 hours ago

You're not "purifying" the water, you're sanitizing it. Purify is a word that has no official definition with regard to total dissolved solids of contaminants, or levels of pathogens in the water.

While iodine used in the proper concentrations can achieve a certain level of reduction in pathogens like fecal coliform bacteria, when you get into parasites, like amoebas, or cysts, like Giardia or Cryptosporidum, you're running risks simply relying on a sanitizing agent such as iodine.

The only effective method for treating water is either to boil it for a set period of time to make sure you're eliminating all pathogens, or to use an absolute filtration system, such as an activated carbon block, a ceramic candle, or a combination of absolute filters (such as a 5 micron pre-filter, a 1 micron absolute filter, and then a post filter at .2 microns, and maybe a UV lamp thrown in for good measure).

People with weak or compromised immune systems are highly susceptible to water-born pathogens, and as such, couldn't safely rely on a method like this.

J2SARET9 hours ago

I worked with a guy who got giardia. It was no fun for him and took him a long time to recover. He had been in the same martial arts/wilderness survival group as I was although at different times so he knew a lot about clean water in the wilderness, but he still got infected. So purify no matter how pure you think your source is. An off taste is better than the alternative. One suggestion: your local camping/mil surplus store can sell you purification pills for a few dollars.

daddio5310 hours ago

Perhaps easiest is not necessarily the best method. After drinking lots of water "purified" using iodine tincture while in the Army, the one thing I can tell for a fact is, the iodine tincture makes the water taste horrible. Therefor, in an emergency situation where you are more concerned with quick water and not good tasting water, then using iodine would be fine. In any other case however, find a "better" way.

Shanball10 hours ago

Good basic instructible for using iodine as one method for purifying water of bacteria/protozoa/parasites. Always a good reminder not to drink water in the wild just cause it's clear (though sometimes straight from a spring is ohhhh soooo good).

That said, WOW the comments are amazing! Ignoring the flaming arguing, there's actually lots of good info between the discussions about the merits of various purifying tactics, and the chemical nature of those methods. Just gotta read through some personal attacking. And cool to see this thread is 7 years old. Still relevant!

tedsan4 years ago
tincture is poisonous, Lugols solution is not. Use Lugols. All of the other halogens, flourine, chlorine, and bromine are also poisonous and replace iodine (which is a necessary nutrient) in the body.
I agree. You may want to simply change Iodine Tincture Solution to 2.2% Lugol's solution. Otherwise, you may have someone who is deathly afraid of Iodine, flag your post and then keep posting over and over about how your instructable "may" kill someone or "may" cause monkeys to fly out of their butt.

Unless you have a very rare case of being allergic to Iodine, Lugol's is not only safe, but actually good for you when taken is reasonable amounts.

Using Lugol's is much healthier for you than chlorine is.

""For many years physicians used potassium iodide in doses starting at 1.5 to 3 gm and up to more than 10 GRAMS (not milligrams) a day, on and off, to treat bronchial asthma and chronic obstructive pulmonary disease with good results and surprisingly few side effects."" !!!

Please read the article yourself:


I sure am glad that the "deadly poisonous, and super duper highly toxic iodine" fear mongering is over now.
dude's before stating that something is poisonous how bout actually looking to see if it is.

Now i AM a chemist and looking up the MSDS it states the ld50 of Lugol's iodine AND tincture of iodine is 30 mg/kg! Why?? Because both Lugol's and tincture are just different ways of solubilising elemental iodine, which is poisonous but your body can hack a bit of it, same as chlorine.

Elemental iodine is very insoluble in water so it needs something to help it dissolve. Lugol's solutions uses a salt "KBr", while tincture uses ethanol and a lot less KBr, or NaBr. Your body can hack alot more ethanol than it can iodine.

This method that has been shown is technically sound, Just don't use two much iodine so you don't kill your liver.

MarkB82 paliaspip10 hours ago
Agreed! I perfer boiling, then add a few drops of lemon flavor. I really don't like iodine flavored ANYTHING. Small block of solid fuel does wonders quickly boiling water!

If you have a choice between Lugol's formula and some xyz brand pushing tainted Iodine, what are you reaching for? and yes, Alcohol is POISON to the body - elementary knowledge. So what if everyone chooses it to subdue their lives - what's that old folk name they call it .. choose your poison..referring to ALCOHOL. Do you know the function of mixing Iodine with Alcohol? Again, why use inferior when you can choose the best. And the body does not 'hack' iodine, it utilizes it. You are a bit mixed up with your logic.

It can't use elemental iodine, at all, actually.


If you're replying to my post, maybe you should read it again. It's called irony.

I should have been more specific though because they're may be a few people around here who are actually dumb enough to put 10 GRAMS of Iodine in their bottle of water. You only need to use the recommended amount to purify water kids, no need to dump the entire bottle in there...
I was actually making a general statement considering all the different posts.
Potassium iodide isn't Lugol's though, just making a differentiation. Potassium iodide is used as a iodine supplement with an ld50 of 2g/kg. Not Lugols! Lugols is KBr + I2 dissolved in water and shouldn't be used as a supplement due to the free iodine, which is toxic
There is nothing toxic about lugols. Don't take my word for anything though. GOOGLE it. It would be illegal to sell lugols as an oral supplement if there was anything poisonous about it.

The same goes for vitamins. You should take one a day. They're good for you. If you try to eat the whole bottle in one sitting though, then YES, vitamins are poisonous.
So, trying to be constructive here, Lugol's has been used as an oral supplement in the past. The reason why it should not be anymore is because IT IS TOXIC. All tests on LD50 that you will find are shown for rats who have a very high tolerance, about 2 g/kg.

However they have done recent human studies and found as I mentioned before a LD50 of 30 mg/kg! Which is a heck of alot less than rats, and why they don't want people to use it, even though you are having a very diluted amount. Any lugol's MSDS within the last few years will state these values.

It is dangerous to say that something is not toxic just because you can buy it of the shelf. Warfarin (rat poison) can be bought as a blood thinner, even though it is extremely deadly. Likewise Lugols IS TOXIC, but can be used at low levels

LD50 studies are NOT performed on humans. What kind of chemist are you, again?

"Lugol's has been used as an oral supplement in the past. The reason why it should not be anymore is because IT IS TOXIC."

And it STILL IS used as an oral supplement. If it were found to be "ToXiC" by any kind of REPUTABLE and CONCLUSIVE source then it would be ILLEGAL to SELL IT as an ORAL SUPPLEMENT.

"Lugols IS TOXIC, but can be used at low levels"

Everything IS TOXIC, but can be used at low levels.

And again (sighs) ANYTHING is TOXIC when used in large enough amounts.

I heard of this guy who went swimming IN PERFECTLY CLEAN WATER and he DIED of water poisoning! He drank SO MUCH of it (here it comes)... it KILLED HIM DEAD!

No more water for me! That stuff is ToXiC!

Here's some more links to different web sites ALL saying that it's perfectly FINE to use Lugol's solution to purify water.




So, what is the name of the guy who was "poisoned" by Lugol's solution? Exactly who is the "they" that you are referring to who conducted these tests? How many controlled tests did they conduct? WHO FUNDED THEIR RESEARCH? How much money is "the human" suing the company for, who tried to poison him with Lugol's solution?

And the best question of all... WHAT HAPPENED TO THAT DARNED RAT? Did he get a tummy ache? Maybe it made him turn into a pumpkin? Exactly what irreversible TOXIC reaction occurred which was so horrifying that it made "they" say:

"The reason why it should not be (used) anymore is because IT IS TOXIC."

Lugol's solution turned that poor rat into a ZOMBIE!!!

I've posted links to numerous places which ALL STATE that it is PERFECTLY SAFE TO USE LUGOL'S SOLUTION TO PURIFY WATER.


Except for the time some guy, in some lab (who probably worked for Pfizer or Bayer) PROVED that Lugol's solution is "toxic" by a test he preformed on ONE rat ...(who was also dying of terminal cancer and AIDS at the time of the test).

paliaspip sounds like he works for the medical white coat industry. Perhaps just brainwashed by it.

I'll just add this-- I have heard of poisoning by tincture of iodine... when someone used the high potency solution instead of the low (It's about 4x stronger) and even then it was for an extended period of time.

Using even 4% tincture of iodine or lugols iodine is perfectly safe for a reasonable period of time as long as the person taking it isn't a complete moron and if they are a complete moron that is a self solving situation.

Chill out everyone, tincture or lugols both work fine and are both safe so long as you don't get stupid or try to live on it extended periods of time.

Given a choice between the two I would use Lugols 1% solution. That being said chlorine is a better solution than either for killing of cryptosporidium or giardia consistently and rapidly.

You use what you can in a pinch and most first aid kits have tincture of iodine in them for wound treatment so it's important to understand how to use it, because you'll likely have access to it even if fairly unprepared.

Lugol's could be very well toxic if used in dose that is non-sense. But in the logical method, it's a life saver and a healer. Your metaphor is amusing but is rather like a smoke screen and I'm not sure if you're just playing dumb or plain dumb. I have used Lugol's for 5 years every day at various doses with only positive effects that I have proof of . It's not a miracle cure, it's a sensible addition to human life.

Something is not necessarily toxic in low levels because it it toxic in high levels. The LD50 of vitamin C is 12 g/kg. Does that mean that vitamin C is toxic? No! The dose determines weather something is toxic or not. Even pure water is toxic when drunk in too large amounts in a short time. If you drink 8 liters of water within an hour you will die because of water intoxication.

Hi Paliaspip. Not questioning whether you are a chemist or not, but I do need to set the record straight. Lugol's does NOT contain KBr and I2. Lugol's contains KI and I2.

The history of Lugol's is that it was invented by a French physician, Dr Jean Lugol in the 1820's for a variety of uses, includin as a dietary iodine supplement. Potassium Iodide (KI) is now considered to be safer than Lugol's. Sure, elemental iodine is poisonous in large doses, for example 2 to 3g is considered dangerous to life.

Consider: in a 50ml bottle of Tincture of Iodine, with 2% elemental iodine, half of which is I2 and half of which is KI, then (ignoring the weight of the K for this exercise) we have around 1.3% K2, or about 15 mg - around 1/200 of the lower of the dangerous doses. The lowest lethal dose (LDL) is 28mg per kg of body weight. Not 28mg - 28mg PER KILO of body weight.

If you were to drink 200 x 50ml bottles of tincture of iodine, then yes, you would be poisoned. As this article is about using 5 to 10 drops of this solution, the only possible danger would be to somebody with an iodine allergy.

I take an 'over the counter' tablet from Wells Pharmaceuticals called Cydiodine Buccal tablets for sore throats. Each tablet contains 1.5mg of elemental iodine, with the advice that not more than 5 tablets to be taken in one day.

The lowest lethal dose (LDL) is 28mg per kg of body weight.

The sky may well be falling, but I'll take my chances with the iodine, and not with the microorganisms!
I use iodine as my main method of purifying water. I rate iodine as the best method for hikers etc.
I stand corrected with KI, my bad for the slip up. Truth be told it will take a bit to kill yourself with iodine. The reason I try to get people to exercise caution with how much iodine they add is because that it takes a big tole on you kidneys. In the "Australian Air force Survival School" they only allow the use of iodine for purification for three days only. After that, it takes to much of a toll on your kidneys.
Excess iodine is not advisable.

Slight correction to that - probaly a typo: Lugol's uses KI, not KBr. Other than that, totally agree with you! Too many panic merchants out there wanting to tell everybody that everything is dangerous!! Tincture and Lugol's both contain elemental Iodine and Potassium Iodide:

USP Tincture of Iodine is defined in the U.S. National Formulary
(NF) as containing in each 100 mL, 1.8 to 2.2 grams of elemental iodine,
and 2.1 to 2.6 grams of sodium iodide. Alcohol is 50 ml and the balance
is purified water.

The 5% solution consists of 5% (wt/v) elemental iodine and 10% (wt/v) potassium iodide mixed in distilled water and has a total iodine content of 126.5 mg/mL.

hinge paliaspip4 years ago
@paliaspip I always thought that Lugol's solution involved NaJ possibly KJ(sodium/potassium iodides).Maybe there's some other Lugol's composition I'm not aware of
sorry Mr.chemist i happen to be a bio-tech engineer not complaining abut any thing but giardia is no bacteria its a deadly parasitic protozoa and it is not really sensitive to to iodine compounds not that much that it will get killed so try simply boiling the water or using chloride water disinfection tablets its much effective than that i guess always peace out
Again.......do your research.

Iodine does inactivate giardia. However it does not inactivate Cryptosporidium cysts, same with chlorine. As far as chlorine goes, it is less favorable to use mainly because of its usable lifespan, 3 days compared with 3 months for iodine, which is the main consideration out bush. But it is faster at killing certain organisms (E. coli). Boiling is more effective than both.

Below is a scientific article that you can look at.

"Efficacy of iodine water purification tablets against Cryptosporidium oocysts and Giardia cysts"

Also for those who use Vitamin C to remove the taste of iodine. Your breakdown product is Hydrogen iodide which has a ld50 of 30 mg/kg, which is just as toxic as the iodine. So still be careful with how much iodine you add!

Doctor Chemist
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