My apologies for not being clearer in my prev. post.

I had an over 3page reply ready exploring a number of different assumptions and various avenues of logic, but who would read it? I didn't even want to proof read it myself!!!

Since i'm so bad with words, let me try numbers and let me take just one part of my never-to-be-published voluminous reply...

Let's go with 5 drops (each drop 1/20 of a ml) on the threads - perhaps(???) more realistic than 5 microliters (physical properties of water at work here, hence my choice of a drop vs. a ul). Let's talk bacteria here since that's what the other Poster had mentioned. Please note that the case is worse for protozoans even in treated water *IF* the water is highly contaminated.

Using the 1 per ul figure from the other Poster's post...

conc./ml, vol. in ml, total #, reduction factor, remaining #
treated: 1000 1000 1000000 0.000001 1(remaining)
untreated: 1000 0.25 250 1 250(remaining)

Add the 250 viable oraganisms back into the liter (as was suggested for the purposes of illustrating the statistics) and drink the liter of water. Has a sufficient disease causing "load" now been ingested? Depends upon a number of factors. This was part of my point on the use of statistics to play a statistical numbers game vs. using non-statistical sort of "real" numbers. My point on flawed logic was just a theoretical #'s game that seemed obvious to me upon reading the other Post that the other Poster posted.

Does this help to explain my difficulty in understanding the meaning of the other post? I'll admit that I'm not the sharpest tool in the shed. What am i missing?

Also, check CDC & FDA/BBB websites. #'s for Giardia & Crypto MUCH lower than quoted by another Poster.

Giardia: "Infectious Dose - Ingestion of one or more cysts may cause disease, as contrasted to most bacterial illnesses where hundreds to thousands of organisms must be consumed to produce illness." [taken fr/ FDA/BBB]

Crypto: "The infectious dose is low; ingestion of as few as 10--30 oocysts has been reported to cause infection in healthy persons" [taken fr/CDC]

Crypto: "Infectious dose--Less than 10 organisms and, presumably, one organism can initiate an infection." [taken fr/ FDA/BBB]



BOTTOM LINE (for me, personally): i'm going to continue to use my UV-C purifiers. I trust them.

Edited by pj on 03/23/2007 04:05:38 MDT.

Re: "How about wiping off the threads with an alcohol pad after drying with a cloth?." I like that idea. An even tastier option might be to use a little Jack Daniels. And when the little wifie complains about the 5th of whiskey you slipped into the bottom of her backpack, simply explain that it is a vital part of the water purification process.

I understand the benefit and efficacy of UV treatment to be the 'inactivation' of the bugs in the water. The UV radiation disrupts the replication DNA so that the nasties can't reproduce. Whatever 'living' bugs are ingested do not blossom into populations capable of causing disease.

This from a Canadian consumer site;

"The ultra-violet rays, similar to the sun’s UV but stronger, alter the nucleic acid (DNA) of viruses, bacteria, molds or parasites, so that they cannot reproduce and are considered inactivated. UV treatment does not alter the water chemically as nothing is added except energy. It should be noted that inactivated microorganisms are not removed from the water. UV treatment does not remove dirt and particles, metals such as lead or iron, or hard minerals such as calcium. Other devices are required to remove particles, metals and minerals..."

In bouncing around from reference to reference trying to understand the theory behind UV water treatment I find a lot of commentary about the "inactivation" of nasties but not a lot of use of the word,"kill." I have seen phrases such as, "...killed or rendered harmless." Perhaps the answer lies in one reference I found, "If the cell cannot reproduce, it is considered dead."

If the SteriPen gets a little smaller I'm gonna bite... :)

PJ,

Here is some more data to back up your conclusions. There has been a lot of studies conducted on water quality here in the Sierra Nevada and Yosemite.

Another report from Stanfurd states that the San Francisco PUC tests for Giardia in both source and treated water at least quarterly and has occasionally (about 23 percent
of the time) detected very low levels of Giardia in
the Hetch Hetchy, East Bay, and San Francisco
Peninsula source waters at an overall average
level of less than 12 Giardia/100 liters of water.

This would indicated that if you were in the Yosemite area, Hetch Hetchy, that you would have 0.000007 cysts in those 5 drops that you left on the threads.

Here is a quote from this web site:

http://www.yosemite.org/naturenotes/Giardia.htm

One conclusion of this paper is that you can indeed contract giardiasis on visits to the Sierra Nevada, but it won’t be from the water. So drink freely and confidently: Proper personal hygiene is far more important in avoiding giardiasis than treating the water.

First, an excerpt written by a highly regarded wilderness physician:

“In recent years, frantic alarms about the perils of giardiasis have aroused exaggerated concern about this infestation. Government agencies, particularly the United States Park Service and the National Forest Service, have filtered hundreds of gallons of water from wilderness streams, found one or two organisms (far less than enough to be infective), and erected garish signs proclaiming the water ‘hazardous."

Here is a picture of the nasty creatures:

Edited by Viktor on 03/21/2007 21:54:02 MDT.

Hi pj

> Giardia: "Infectious Dose - Ingestion of one or more cysts may cause disease, as contrasted to most bacterial illnesses where hundreds to thousands of organisms must be consumed to produce illness." [taken fr/ FDA/BBB]
Hum - the references I saw use a threshold of ten, not one. Ah well, just one log unit ... :-)

> Some viruses can multiply in the squamous epithelial cells lining the intestines, viz. so-called intestinal "flu" of viral origin. Who here in the Forums has never had a so-called 24-hr intestinal "grip"/"flu"? Please raise your hand. I learned in class that these are often of viral origin.
Yep, such things exist, but by the time you are a responsible adult you have probably developed *some* resistance or tolerance. And, as the name implies, after 24 hours your body has usually got on top of it - unlike some of the other bugs.

But, you know, there are hordes of walkers out there who never treat their drinking water at all - and they survive. One wonders, while staggering up the hill with all that heavy expensive water treatment gear on board, whether the risk is quite as great as the vendors of the same expensive water treatment gear claim... Dunno.
Me, I wash my hands with a little bit of soap and water every time, and before I prepare dinner.

Roger,

I'd have to agree with you. For decades my friends and i drank freely of water sources here in the NE. Sometimes we'd get some mild intestinal problems - often at home, or rarely on the trail. Was it from the water, or did we acquire it at home either b/f or aft. the trek? Probably no way to know without a stool examination.

Only started treating the water when i "learned" that i should treat it.

Even with water treatment methods "on board", so to speak, i still pass on still, stagnant, smelly, suspect sources *IF* at all possible. Just the smell and taste(???) alone (chemicals from either decomposition or agriculture) makes me want to pass - even if i could eliminate any and all biological threats.

I think that out this way with a greater farm density and lower elevations our water sources MAY have a chance of being more contaminated than high up in the mountains out west in the USofA.

Oh, BTW, i've removed some of my prev. comments. Don't know what i was thinking putting just that info there - very misleading and to a degree just plain wrong; as it didn't represent accurately the spectrum of lower intestinal ailments. That's why i checked in here, and found your reply, as it popped into my head what i wrote to you and it was very misleading, it's not really the direct reason one gets the runs - my apologies.

As far as "one" - check the quotes i excerpted and placed in the prev post. The words "presumably" are there assoc. w/"one". The indicates something good and possibly something bad. More good than bad perhaps. I guessing that what they're thinking of is a particularly virulent strain and a person who has poor resistance. Again, the theoretical is often what is expressed even if, practically speaking, the chances are extremely small that such would occur.

Victor,

you're right (and Roger is, again, certainly right - IMO).

protozoans usually have much lower concentrations than bacteria - some protozoans feed on bacteria - food chain stuff and what a food chain can support. in fact, even the 1 per ul is probably(???) higher for bacteria than one will usually find in the wild (i'm more familiar with potable well water than surface water where it's much lower - 1 per ml or less, typically).

while researching (finally starting to use the web more for this; thanks guys for teaching an "old dog" a new trick) i came across a study that found from many samples that 10 protozoans per liter were demonstrated in untreated water - pretty low numbers.

i know from ponds sometimes i've found at least one in every drop, or at least one in every two-to-several drops - much, much higher concentrations, but then i was selecting my sample in what i thought was a location that would be higher in conc. of the lil' buggers since i wanted to see which ones where there - not representative of what would be in the water source i would select, if at all possible, for drinking water while on a trek.

Oh,...the other thing i want to make clear is that wiping (and dipping a point of absorbent pac-towel, etc. into tighter places in the cap and allowing capillary action to draw up the water) the threads of bottle & cap and merely absorbing the hypothetical FIVE DROPS, leaving trace amounts, blows the numbers that i was expressing away. Essentially, very little and close to nil would be left.

i still y'all out west might have cleaner water (lower farm density and higher elevations) than we have in NE.

dbl-post.

past few days Forums have been extremely slow for me with 5-10 minutes elapsing (without timeouts) when displaying Forum pages or Posting.

Closing Browser window via the normal fashion (closes immediately indicating that Firefox is not "locked up") and opening another, sometimes shows that Posts have been posted, other times not.

Think problem is on BPL server end.

Edited by pj on 03/23/2007 05:12:04 MDT.

>past few days Forums have been extremely slow for me with 5-10 minutes elapsing (without timeouts) when displaying Forum pages or Posting.[...]Think problem is on BPL server end.


I haven't noticed that. Unlike normal, where I go through and read everything once every day or so, the last few days I've been 'working' so I sit here and refresh the Recent Posts list and read the new posts every hour or so. Haven't notice any performance problems with BPL at all, i.e., no more than 10 seconds to load a page at any time.

Sorry for going off-topic.


The discussion is, of course, interesting. But pragmatically, I'm not going to worry about it because the chances are extremely low that I'm going to get sick with any reasonable choice in water treatment, even if there are a few unsterilized drops. My spoon is probably a larger threat. I have a fair selection of water treatment options, but the number one reason I take the UV AquaStar (3.8 oz including batteries), except in winter, is that I can drink cool fresh stream water in the mountains as I did when I was a kid carrying only a plastic cup. I dip a liter of fresh stream water, zap it, and drink it. No flavor change, no chemicals, no wait. Depending on the location and time of year I might bring something to pre-filter the water, but most of the places I hike have clear streams. Just lucky, I guess. The AquaStar fits nicely on a 1L lexan Nalgene bottle (4.7 oz), but it also works on a Nalgene Cantene (1L: 2.1 oz including redundant lid) or a MSR Hydromedary (2L bag: 2.3 oz). This also reduces my total weight by nearly a kilo, as I don't have to carry the liter of water while it's being treated, as I do with Aqua Mira. The AquaStar doesn't weigh much more than the two full bottles of Aqua Mira (3.2 oz), either. In the winter I use Aqua Mira, since my water is either being boiled, or just melted and sitting overnight for use the next day. No sense trying to keep batteries warm when the chemical taste/smell of AM is totally gone by morning.

Come on now, you can't seriously be worried about a microliter of untreated water. This guy wasn't:
http://www.backpackinglight.com/cgi-bin/backpackinglight/sipping_water_drinking_untreated_backcountry_water.html

You have more of a chance of getting sick by not washing you hands when you grab some trail mix, poor personal hygiene and running your immune system down. More crypto cases are due to poor hand washing techniques than drinking tainted water.

agree with David on the hygiene being the main culprit to backcountry sickness.

Also Douglas is right on with his treatment style. I switched over to my Steripen and have not looked back since. Much, much better than chemicals!!!

I'm pleased to see this review and all the comments, and even more pleased that Miles is monitoring the discussion. Thank you.

I have to agree that the requirement of a wide-mouth container is forcing me to carry heavier and BULKIER containers thus reducing the weight advantage of the Steripen over my filter. Especially since I consider a pre-filter necessary too for use with the Steripen.

Recently I have moved to a ~1.6oz mayonaise jar (about 1L capacity) as an alternative to the ~3.5oz Nalgene bottle.

One contribution I can make regarding an area for improvement has to do with the location and/or brightness of the LED. When in bright light conditions I cannot easily see either the light from the pen nor the teeny LED. This is more than a moderate irritation, as you may imagine, and has probably resulted in multiple treatments of the same water.

Best regards,
Tim

Edited by ThinAir on 06/07/2007 15:03:53 MDT.

I reduce packweight by drinking all the protozoa and cysts I can! With each 50 gallons of unfiltered, untreated water consumed I gain as much as 1 gram in protein and can reduce my foodweight by an equal amount. I know that chemical and UV treatments don't remove these flavorful tid-bits but they do harm them, cruelly and inhumanly. I prefer my viruses and bacteria in a pure, fresh form. :}

But seriously, I was drawn to this stimulating thread because I'm trying to figure out which device to buy, Aquastar or Steripen. These's no clear comparisson presented here, but I think I'll go with the Aquastar. It's cheaper, can be used as a lamp, comes with a pre-filter and seems easier to operate (screw in and swirl, no need to stir). The drawback is that it requires a wide mouth container to screw into.

Can anyone who has experience with both devices comment about which one they prefer?

I hike in the Sierras alot and normally don't treat water at all. As you might guess, a few drops of "dirty" water on a bottle rim don't cause me much grief. I do use an in-line filter when I'm not happy with the water sources available but UV-C looks like a better way to go.

Sherpa Chris

>>"It may be very helpful to remember that, apart from the Energiser e2 lithiums, ALL the rest of the lithiums have a water-based electrolyte and, like alkalines, they all freeze up in the cold. They won't work below freezing!"

Roger, that statement has been bugging me for some time. Li reacts violently with water releasing hydrogen and oxygen gas, hence Li fires are self-fueling, IIRC (not a good thing to say the least). I don't believe any Li battery (primary or secondary for that matter) uses water. This is also why water is NOT used to put out a Li fire. I believe, if i have my Classes right, it must be a Class IV fire extinguisher, or a dry chemical (is that the same thing as a Class IV???) extinguisher that is used to put the fire out.

We recently had some Mg shavings in a large dumpster go up at work at ~0300 one morning - i was there to watch 4hrs of fireworks with flames over 100' in the air - looked 100x better than the scene from Raiders of the Lost Ark where the Nazi fuel dump goes up. The fire dept. hit it with water - BIG MISTAKE!!! - WHAT AN EXPLOSION. There after they tested it a few times by spraying a short burst of water up in the air, and letting it sprinkle down on the dumpsters (yes, multiple nearby ones ended up igniting). Yup, still burning!! Only stopped when all of the "fuel" was spent!!

This is why pieces started falling in place in my mind about what i had recalled reading in the Post to which i am replying.

Maybe i'm misunderstanding what you wrote. Please correct me. Many thanks, pj

Edited by pj on 07/23/2007 06:44:03 MDT.

Nice to have you back, pj.

Thank you, Dondo. i'm off from work the last couple of weeks temporarily on partial disability. So, when i'm feeling up to it, i'll check in evey once in a while. My trekkin' days, however, are undoubtedly o'er - even after surgery; at least that's what i'm told.

i'm still trying to figure out what to do with my gear - much of it unused or lightly used (some heavily used, but still looks nice - i'm very OCD about keeping my gear in good shape and not abusing it). i have a lot unused simply because, when i find a piece of gear i really like, i buy another one later on before it's no longer manufactured (this has happened to me in the past), and then store it unused.

i'm open to suggestions on how to divest myself of this gear at very low prices, to others who will put them to good use (both unused and very lightly used - i can't seem to mentally part with some of my "old friends" that have served me so well even if i'll never be able to use them again).

Edited by pj on 07/23/2007 06:52:30 MDT.

I'm sorry to hear that your trekkin' days are over, pj. That must be a tough adjustment.

As far as your gear is concerned, I'm sure the good people here will help you divest. :-D

PJ - I too missed your well researched and well written posts. What happened to cause your disability?

pj, sorry to hear your hiking prognosis. I hope you will be able to advise us with your wise gear research and entertain us with your dry wit for a long time to come. I was a newbie to forums, and of course this site when I started reading your posts, lo many months ago.. now people occasionally thank me for constructing a well-worded post; something I learned from you. This watering hole of gear knowledge has been just a little dry since your previous departure. Welcome back.

Hi, PJ. Welcome back! Don't totally be BPL Forum Poster Emeritus. :-)>