Chlorine Dioxide Tablets for Crypto? NOPE!

Chlorine Dioxide Tablets for Crypto? NOPE!
HERE

So I am still good by boiling the water for tea?

Boiling and UV devices (For the PSK or BOB, I only know of the SteriPen; HERE ) are the only viable ways to be maximally safe from all waterborne micro-organisms.

It seems fine filtration can never be too fine; viruses WILL get through. Iodine can kill some pathogens, but usually takes quite a while, and can only merely reduce the numbers of other pathogen species.

Fine filtration AND iodine or chlorine dioxide can be effective, at least in theory. But if one organism is known to be resistant to iodine, it is logical to assume so might be another, perhaps one not yet discovered or not yet fully understood. Also, what we now know about certain microrganisms is not necessarily definitive and universal knowledge, as individual populations of microorganisms might for whatever reason (i.e. global warming; pollution having an unnatural nutritional or hormonal effect; genetic manipulation and release into the environment) mutate and experience accelerated evolutionary changes making them more chem-resistant, smaller, and/or more able to conform/deform during filtration. Survival of the fittest, Baby!

I am fond of my little bottle of Polar Pure as it is so self-contained and perpetual. Too bad it must be replaced.

I am not so sure I would give too much credibility to a single report such as this given that Chlorine Dioxide tabs have passed the extremely stringent EPA tests. Note also the date and it seems this has suddenly turned up all over after being publicized by placement on the Steri-Pen site. In any case, I'm researching this further.

I agree about not trusting one report much less one that is posted on the Steripen site. I will say this (even though I am a strong supporter of steripen) that UV light has been extremely effective through many of my industrial career paths using ultra high pure water systems including (Lucent Technologies) and Nasa and that was another one of my decisions over the Miox.

On the other defense MSR and katadyn are very well established companies and I think that their products would work providing you wait the 4 hours. I have some micropurs as back up for the steripen but I haven't had any failures on mine and this last trip I went on ran up some good lamp time on the unit. I will be anxious to see what Doug pulls up with more updated accurate reports. One thing I know is I've never gotten sick off a steripen yet. As long as the lamp and circuit is good, I can run it with or without batteries in daylight for an indefinite amount of time. No need to carry salt,wood and tinder or tons of tablets. But tablets have there advantages as well too.

Chlorine dioxide is not 100% effective against crypto
Comparing the efficacy of chlorine, ch...outhern Brazil.

Ozone is effective and acts 3200 times faster than Chlorine dioxide Ozone Food Sanitation

But I don't know about "portable" Ozone generators... New market for somebody?

UV is effective against crypto
Pulsed-UV light inactivation of Cryptosporidium parvum.
Inactivation credit of UV radiation for ...ater: a review.

Ozone is readily generated by electric arc in the atmosphere. Collecting and concentrating it not quite as easy.

UV may not be as effective in water with significant turbidity. If light can't pass through it so well, neither will the UV.

I will be interested in what Doug finds out.
In the mean time I will keep drinking tea when I camp.

If I was where I had no way to treat the water and risked dying of thirst, I would drink the water and risk just getting sick instead of dying.

Even if the bleach tablets do not kill all the Crypto it takes care of almost everything else, and I would rather have a treatable case of Crypto than be dead.

Note that Crypto usually takes a week and a half to hit you and usually only lasts a couple of weeks.
(It is harder on kids, the old, and aids victims.)

I would worry more about stuff like Tularemia, Dysentery and Cholera.

I think we all know nothing is always 100% effective when it comes to sanitation. Fortunately, mere exposure to these organisms isn't always clinically significant. It generally takes more than a single cyst or bacterium entering your gut to make you sick. It may take hundreds, or more, and even then you may still not get sick. The object here is to reduce your odds as much as you can.

General sanitation also plays a part. A large percentage of supposed back-country gastrointestinal "waterborne illness" is most likely fecal-oral or other types of infection by routes involving the hands, cook wear, water bottles, clothing, foodstuffs, etc., and not the water supply.

I either don't worry about it overmuch, and trust my luck and iodine crystals or filter, or I double up and use both when I am feeling doubtful about my water source. I also try to let the iodine work overnight, for maximum contact time, then filter it. I have a large "dirty water" bag for this, then I filter it directly into my water bladder and bottles.

For anyone who is interested in really safe water, here is what our DMAT team uses:

Jeff

You need to read those studies VERY carefully.

The first one listed by Troglodyte007 gives a detailed description of the methodology used. The second study is only an abstract, so we don't know what the methodology was. There is a 3rd study out there that some tru to use to prove that chlorine dioxide and MIOX are ineffective, but there is a catch.

In the studies they take a water sample with a relatively high concentration of "bugs", add one dose of MSR MIOX solution, stir, wait 4 hours, and then test for the number of bugs still viable. The problem is, that is NOT the method recommended in the MRS Miox User Manual.

In short, the user manual tells you to use test strips to check the MIOX dosed water for sufficient residual (left-over) chlorine before you let the treated water sit for the prescribed period of time. The idea is to put enough MIOX solution in until at least a little residual chlorine is left over after killing the bugs. The MSR Miox protects users by using those purple test strips to make sure at least 4 PPM of residual chlorine remains.

If you treat water with a high concentration of organics (bugs) with just one dose of MIOX solution, and don't use the test strips, the chlorine gets used up before it kills all the bugs, thus it is not effective. Its not rocket science.

The author of the article adds just one dose into sewer water and that's it. No checking for residual chlorine. Of course it won't work.

By the way, the MSR MIOX instructions say that if you don't want to use the test strips you should add 4 doses of solution to be safe. They also suggest that you can use the test strips just the first time you use water from a particular source, than then you may not need to use them after that. Still, they warn to either use the test strips for each new water source, OR use 4X dosage. Lots of folks who are using "familiar" water sources just add a 2X dosage to be safe.

BTW, I've been told that someone once went all over the country gathering ambient Giardia and/or Crypto conentrations from natural lakes and streams all over the U.S. I'l love to see that. The point is that it takes more than one of these oocysts to cause an issue. If the efficiveness in 10 minutes is, say, only 90%. If you start with a solution with only maybe 20 oocysts, that means, the odds are that teh purification will be completely sufficient. I think Doug mentions that in his discussion of the MIOX at equipped.org.

Ken K.

I'm no scientist, but I play with them at work. We host the country's only NIH bacterial pathogen bioinformatics resource center, and have close ties with the other BRCs, including the parasite folks. I'll make a few inquiries when I get back from vacation.

On first glance, this article looks like an industry plant. MB Lee, according to PubMed (THE source for bio-med research), has exactly this one article to his (?) credit, which screams grad student to me, and not a very good one either. The grad students in my building all have multiple pubs. It is hard to tell, of course, because of the multitude of M. Lees that could also be him/her.

Vetech looks like an Agri-biz that makes poultry vaccines. Why would a top-flight parasitologist be making chicken shots?

Something smells, here.

The line that really jumped out at me is the one, near the end, where they admit that they use conditions that no one is likely to encounter. Basically, they are using a sample full of a strong lab strain of cysts, at a level that simply does not occur in nature.

Bull**it. In more ways than one.

Making an ozone generator is not that hard. Glass, stainless mesh, wire, hot glue, high voltage transformer from neon sign. Making one that works on water... not to sure about that

I`ll stick to boiling.

The EPA’s own study on the effectiveness of chlorine dioxide can be found in the Alternative Disinfectants and Oxidants Guidance Manual (EPA 815-R-99-014, April 1999). The pertinent section will be found at the bottom of the (virtual) page 19, which is (document) page 4-19, section 4.4.3.2.

If someone knows the dosage measurement in grams of the Micropur MP1 tablets, a comparison to the EPA published results can be made.

Maybe I am mistaken (I skimmed hastily through those pages), but I see the report says that chlorine dioxide only reduces crypto efficacy, and then after 30 minutes contact time. Dosage shmosage, chlorine dioxide isn't 100% effective. But all is well, because fire (boiling) is 100% effective at killing ALL microorganisms.

And it takes only 1 oocyst to cause infection.

I interpreted the report differently. The sentence you are referring to:

“Although some Cryptosporidium oocysts remained viable, one group of researchers found that a 30-minute contact time with 0.22 mg/L chlorine dioxide could significantly reduce oocyst infectivity (Peeters et al., 1989).”

… is immediately followed by:

“In contrast, other researchers have found that CT values in the range of 60 to 80 mg·min/L were necessary to provide 1- to 1.5-log inactivation (Korich et al., 1990; Ransome et al., 1993). Finch et al. (1995) reported that the CT values for 1-log inactivation was in the range of 27 to 30 mg·min/L. For 2-log inactivation, the CT value was approximately 40 mg·min/L, and 70 mg·min/L for 3-log inactivation. Finch et al. (1997) found 3-log inactivation of Cryptosporidium oocysts with initial chlorine dioxide residual concentrations of 2.7 and 3.3 mg/L for contact times of 120 minutes, at pH of 8.0 and a temperature of 22°C.”

The “in contrast” the second part seems to refer to the contract between reducing the Cryptosporidium infectivity and the actual complete, measureable inactivation of the Cryptosporidium oocysts.


You are correct. Chlorine dioxide is not 100% effective. This paper simply lays out the dosages and contact times as well as their effectiveness for both Giardia and Cryptosporidium. It shows the difference in difference in resistance between Giardia and Cryptosporidium, but it lists methods of obtaining the same level of disinfection (3-log, i.e., 99.9% I believe) of both. The report lays out the reality pretty well in one sentence:

“Both studies concluded that chlorine dioxide is an excellent disinfectant against cysts and that chlorine dioxide is better than or equal to chlorine in terms of inactivation. Chlorine dioxide was found to be superior to chlorine at higher pHs.”

Now, for credibility, that sentence applies directly to the disinfection of Naegleria gruberi, however it seems to be true for Cryptosporidium as well when looking at the EPA results on regular chlorine (Alternative Disinfectants and Oxidants Guidance Manual (EPA 815-R-99-014, April 1999): Chapter 2 — Page 37 (2-37), Section 2.7.4.3):

“Chlorine has little impact on the viability of Cryptosporidium oocysts when used at the relatively low doses encountered in water treatment (e.g., 5 mg/L). Approximately 40 percent removals (0.2 log) of Cryptosporidium were achieved at CT values of both 30 and 3,600 mg·min/L (Finch et al., 1994). Another study determined that “no practical inactivation was observed” when oocysts were exposed to free chlorine concentrations ranging from 5 to 80 mg/L at pH 8, a temperature of 22°C, and contact times of 48 to 245 minutes (Gyürék et al., 1996). CT values ranging from 3,000 to 4,000 mg·min/L were required to achieve 1-log of Cryptosporidium inactivation at pH 6.0 and temperature of 22°C. During this study, one trial in which oocysts were exposed to 80 mg/L of free chlorine for 120 minutes was found to produce greater than 3-logs of inactivation.”

And it is easily verified that chlorine dioxide is significantly more effective against Cryptosporidium than iodine.


This is presumed true, and the statement deserves qualification, despite its being presumed technically true.

http://www.foodsafety.gov/~mow/chap24.html
“Infectious dose--Less than 10 organisms and, presumably, one organism can initiate an infection.”

One can be infected due to only one viable Cryptosporidium oocyst. That does not mean that you will be infected if there is even one viable Cryptosporidium oocyst in the water you drink.

The basic point is this: Does chlorine dioxide eliminate any chance of being infected by wild ground water? No, it does not. Neither does any other treatment. Even the effective time for boiling is debated, and even distillation does not remove 100% of everything, and I have not even mentioned how difficult it is to carry your firewood in a pocket. There really is no such thing as the elimination of the chance.

So, take chlorine dioxide for what it is. It is a self-contained, portable solution for significantly reducing your chances of infection as long as it is used correctly. It is meant to replace regular chlorine and iodine, which have shown to be ineffective at inactivating Cryptosporidium at dosages safe for human consumption. It is not meant to replace filters or boiling or even UV treatment; it is meant only to be the next generation of self-contained chemical treatments.

You cannot view this issue with a black and white monitor, and you will be severely handicapped even with 256 shades of gray. You have to switch into the 16 million color range for this, because there are multiple different categories of water treatment, and each item in each category has a different effectiveness. You cannot just measure one item against another when the items are a different beast altogether.

And on a side note, for anyone who is interested, one of the better no-fluff breakdowns of all the different methods of water treatment can be found at http://zenbackpacking.net/WaterFilterPurifierTreatment.htm. Can anyone find an updated link to the Army’s chart on the different treatments and their ratings? It looks like the Army moved or removed the page and did not supply a redirect.

From what I've read that simply is not true. I've found articles that say 2-10 oocysts can cause illness in animals (not sure how that related to humans), but the health of the person has a lot to do with it.

Here is a really good article on these nasty bugs in the wild (and other places):

http://www.webcitation.org/5bd7Yos7y

Another data point is that the hardcore folks who run BackPackingLight.com have used AquaMira (chlorine dioxide) in water taken from places like livestock animal watering troughs multiple times and fared well. No, this is not 100% scientific proof, it is admittedly anecdotal and who knows if crypto was even in that water. But, I wonder how much field water M.B. Lee has drank for real.