SteriPEN Adventurer Water Purifier REVIEW

>>"Now a microliter is 1 milionth of a liter – so, if you were to take a liter of stream water, and treat it with the steriPEN you could expect to have destroyed in excess of 99.9999% of the bacteria present. And you could consider this the same as destroying all the bacteria in 999,999 microliters of that liter – with the 1 remaining microliter not purified.

Following this line of thinking, lets say you treat the water with the SteriPEN and then neglect to dry off 5 microliters of droplets on the threads. In this case the effective SteriPEN treatment would indeed have been reduced but it is worth noting that the reduction would be from +99.9999% to about 99.9994%."

I believe this line of "thinking" and application of statistics is severely flawed. If you somehow(???) consume the untreated water, then the effectiveness, as far as the untreated water goes, of any UV-C purifier is 0% (ZERO percent)!!!

The reductions mentioned, which i accept without reservation or question, apply to TREATED water, NOT UNTREATED water. There is no guarentee that a "clump" or bunch of organisms is NOT present at much higher levels than would be indicated by the reduction observed in treated water. Again, the reductions apply only to treated water. One would need to do an entirely different survey/study to determine how many organisms per microliter of untreated water for the probability of consuming sufficient numbers of pathogenic organisms to produce disease (ONE cyst is sufficient in the case of Crypto is the current thinking of some working in this field, though other organsims are generally required in higher numbers to produce disease just as the original Poster indicated).

Those LOG reductions for treated water simply DO NOT APPLY to untreated water and are NO BASIS in which to place one's trust for untreated water left to contaminate bottle/cap threads.

Just for the purposes of visualization (though this number is by no means fixed and inviolate – it depends upon several factors), 20 drops from a typical laboratory pipette is approx. one milliliter. Think about how larger or small (depending upon one's perspective) this is. A microliter would of course be 1/50th as small as this somewhat typical drop. In well water (which in many homes is not treated with any chems or UV-C light), over 100 non-pathogenic organisms per milliliter can be found (i worked one Spring through Fall in an environmental soil & water testing lab a long time ago [deleted unecessary info that added no value to Post – was just typing what went through my head at the moment, i.e. memories, at the time w/o giving much thought; my apologies.]).

This is just to give a frame of reference for how tiny these little buggers are and how many may be found in untreated water. Depending upon conditions, above ground water may have more or less than untreated well water. Now if the water is contaminated, the numbers of pathogens could be high also. This is to further illustrate the flaw in the above "thinking".

Don't get me wrong, i own both the SteriPen and AquaStarPlus – trust them both to do the job. They are both very fine units, IMO, when used properly.

Please delete the duplicate posts leaving only the latest/most-recent one.

Many thanks,
pj

In case Admin is interested, here's what transpired:

1)clicked "Post Message" – Firefox "throbber" showed activity – never stopped.
2) opened new Firefox window & searched Forums – my Post was NOT present.
3) pasted text of Post into new reply and clicked "Post Message" with same result.

Repeated the above sequence several times, with the attendant result.

No Worries, PJ!

sorry double post

I have used the original Steri-pen with the pre-filter for about a year now with no major issues. There is a learning curve with all new gear, but this one is fairly easy to master. I'm not a fan of chemicals and the field maintenance of mechanical filtration can be a pain. As far as batteries are concerned, I would buy the best available. Why squabble about a few $ when you just spent > $100 on the pen. A couple of well spent $$ are still cheaper than the medication needed to treat the diseases you may get.

> > How can you treat the threads with the AquaStar?
> I pour sterilized water over the threads the same way and hope that washes the nasties off.

I agree.

It is important to understand that you do NOT have to eliminate every single bug in the water you drink. Your body can cope with a certain amount all the time: if you couldn't then you would be like one of those kids who have to live their whole life inside a sterile plastic tent.

In fact, current medical thinking is that the increasing amount of asthma seen in kids in affluent society these days is due to them being brought up in a TOO sterile environment. You need exposure to a low level of bugs to keep your immune system working.

What is important is to REDUCE the number of bugs you get at any one time. Think of it in terms of salty water. You have a bottle of salty water – too salty to drink. You wave your magic salt remover over the bottle and remove all the salt from inside it – but there are a few drops of salty water left on the threads. Then you pour the bottle into a drinking cup, and some of the salty water on the threads gets picked up along the way. Will you taste the salt in those few drops? Most unlikely.
EXACTLY the same argument applies in the case of bugs.

Of course, if the initial concentration of bugs in the water was a million times higher than the lethal dose, things would be different. But we just don't get those sorts of concentrations in the wild. Bio-warfare lab beaker maybe …

I admit to vast ignorance on this matter, but I question the correctness of using a phrase like a "lethal dose," and I question the wisdom of comparing a living, growing organism to the concentration of a non-living substance like salt. Letting into the body a little salt won't lead to more salt being generated. Letting in a few virii against which the body has no anti-bodies, say HIV, seems to me to run the risk of letting those virii begin to grow and multiply and multiply and multiply. I know HIV is not a threat in water. But what about those virii that are? My question, and I do NOT know the answer, is, why could not just a tiny few start to grow, and grow, and multiply and multiply?

I got my SteriPEN today and have been playing with it around the house. I'll have to fool with it a bit but it will require some changes in my gear… most notably I'll have to go to a wide-mouth collapsible water container rather than the 1l Platys I have used for years. That's a huge bummer because the SteriPEN was already suffering a weight penalty and now I have to carry heavier water bottles. I wish there was an attachment for the UV bulb for the Platy bottles… probably easily enough built but then I would have to find a way to defeat the safety interlock that detects if the unit is submerged in water.

The batteries that come with the unit are OK to play with but I will test the unit with SureFire batteries (I use these with my testing of the MIOX and they are outstanding batteries in my experience).

My son is fascinated with the thing. I have a lot of SUPER STERILE city water now. :)

Hi PJ,
This is Miles Maiden again (from Hydro-Photon – makers of SteriPEN). I just wanted to comment on your comments.
Evaluation of water treatment systems such as filters, chemicals and UV devices, is generally done by testing in accordance with recognized protocols. While there are numerous microbiological test protocols, the most widely recognized and most commonly cited are from the US EPA (US EPA Guide Standard and Protocol for Testing Microbiological Water Purifiers) and NSF (several protocols including NSF Standards 53, 55 and P231). The EPA protocol was largely written by one of the world’s foremost microbiologists and experts on infectious disease – Dr. Charles Gerba of U. Arizona. The NSF standards vary slightly but incorporate key elements of the EPA protocol.

Both the EPA and NSF protocols assume that the water volume being tested is basically homogenous – so samples taken from a volume of test water are considered to be representative of the whole volume. The EPA and NSF protocols do however, require that testing be done in triplicate (using 3 of the same water treatment devices) so that variations in device performance can be averaged.

Additionally, both the EPA and NSF protocols call for reduction rather than elimination of microbes. The required levels of reduction are expressed as logs of reduction – 1 log of reduction equals 90% reduction, a 2 log reduction equals 99, 3 logs equals a 99.9%, 4 logs equals 99.99% and so on. So, none of these protocols require treatment to result in less than a particular maximum number of microbes per unit volume of water – rather they require a minimum level of reduction of microbes. For bacteria this minimum level is 6 logs (99.9999%). For virus it is 4 logs (99.99%) and for protozoa – like cryptosporidium and giardia – it is 3 logs (99.9%).

Now, I want to try and speak to your points. While you are correct that we may not know how many microbes are present in a given microliter of water, if we use the EPA and NSF approach, then we know that whatever the number of microbes in that microliter, there are one million times that many in the full liter. By simple math we know that for every untreated microliter within the otherwise treated liter we can reduce the microbial reduction by .0001%. So, as I said in my earlier post, 5 untreated microliters added back to a treated volume would give you a total reduction of 99.9994% (5 added microliters and effectively, 1 microliter that SteriPEN missed).

To your point about the possibility that a “clump” of organisms – a much higher concentration of organisms than in the rest of the liter – may be in the untreated microliters – this is of course possible. However it is far more likely that the concentration of viable microbes will be in line with the rest of the liter prior to treatment. Again, it is for this reason that the EPA and NSF require only that samples be tested rather than the entire volume of water – statistically, the samples are representative of the larger volume.

So, to conclude, one may take issue with the validity of the EPA and NSF protocols, however they were created by some world-class scientists with a level of knowledge that is not easy to dismiss. If we accept the EPA and NSF protocols (which almost all water treatment system manufacturers do) as valid then we conclude that particular water volumes are statistically homogenous and that logs of reduction are a valid measure of treatment effectiveness. Following from this logic, the “clump” of microbes, while possible, is highly improbable. And the effect of untreated droplets relative to the treated volume does apply as the droplets and volume combined can be shown to have a particular log reduction.

Final note: while there is lots of work on Cryptosporidium out there, the bulk of the material I have seen shows infectious dose for humans of anywhere from 50 to 200 Oocysts.

Hi Robert

> I question the wisdom of comparing a living, growing organism to the concentration of a non-living substance like salt. Letting into the body a little salt won't lead to more salt being generated. Letting in a few virii against which the body has no anti-bodies, say HIV, seems to me to run the risk of letting those virii begin to grow and multiply and multiply and multiply. I know HIV is not a threat in water. But what about those virii that are? My question, and I do NOT know the answer, is, why could not just a tiny few start to grow, and grow, and multiply and multiply?

Well, good question. I used the analogy to clarify the dilution aspect, and I stand by it for that purpose.

However, with bugs it isn't a simple matter of 'letting into the body …': you have to ask where in the body and what sort of bugs.

HIV gets into the bloodstream either via micro-tears in sensitive membranes or through those sensitive membranes. Once in the bloodstream, yeah, multiplication is possible. Nasty.

But bugs in the water go into your stomach. That is a very different environment. Your stomach is capable of handling quite a lot of nasties – the contents of your stomach is quite acidic and many things don't survive long there. Some bugs do, and can pass into your intestines, but your body is usually able to control a certain amount of infection. It is only when your body's defences are overwhelmed that there is a problem.

Now in fact viruses usually need to be inside a cell to multiply, and that is not going to happen in your intestines. Some bacteria can multiply in your gut, if the ddefenses don't get them. Protozoa can multiply in your gut if the defenses are overwhelmed.

Bottom line: I rely on the EPA for the technical questions here. I am a physicist, not a microbiologist!

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.

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:

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.

>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

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

Nice to have you back, pj.