Results 26 to 50 of 90
-
07-01-2013, 08:53 PM #26
I am a fan of the first need. Super easy to use and clean. I highly recommend it.
http://www.backcountry.com/first-nee...elite-purifier
-
07-02-2013, 07:56 AM #27Registered User
- Join Date
- Nov 2007
- Location
- So. VT
- Posts
- 2,829
-
07-02-2013, 08:03 AM #28
From http://www.lightandmatter.com/article/hiking_water.html
Don't have time to find all the studies but this guy seems to sum it up nicely. That said I treat most of my water. Pissing out my ass for a week doesn't sound like much fun.
"Many people who experience diarrhea while backpacking automatically attribute the problem to Giardia, which is the most popularly known microorganism that can contaminate backcountry water supplies. Among weekend backpackers, it is almost certain that any illness during the hike itself was not caused by wilderness-acquired Giardia, which has a typical incubation period of about a week or two.[Erlandsen 1984, Jokipii; see more detailed information in the footnotes]
Giardia is a big problem in daycare centers and public swimming pools, but recent data show that its prevalence in the backcountry has been wildly exaggerated. In a survey of 69 sites in the Sierra, every site had concentrations of Giardia cysts much too low to make anyone sick.[Rockwell 2002] Studies on prison volunteers show that a minimum of about 10-25 cysts is necessary to cause disease,[Cox 2002] and even at the most contaminated site in the survey, a hiker could only have swallowed this many of the bugs by drinking hundreds of liters of water.[Rockwell 2002] In fact, 67 out of the 69 sites had concentrations lower than 0.03 per liter,[Rockwell 2002] which is the typical concentration found in San Francisco and Los Angeles tap water.[Rockwell 2002,sfwater 2009] Elsewhere in the U.S., similar testing[Jaret 2003] also failed to turn up any concentrations of cysts capable of causing disease at any of the backcountry locations tested: West Beaver Creek, AZ; Merced River, CA; Chattooga River, NC; Neversink River, NY; White Pine Lake, UT; Greenwater River, WA; and Renard Lake, WI.
Giardiasis is extremely common among the population of the U.S., with roughly a third of toddlers having it.[Ish-Horowicz 1989] Most people who have giardiasis have no symptoms, and there is even some evidence that children who are asymptomatic carriers are actually healthier than those who aren't infected at all.[Ish-Horowicz 1989] Giardiasis cases peak in the summer, probably because people swim in public pools used by diaper-age children.[Furness 2000] Very few people who believe they contracted giardiasis from backcountry water ever get tested for it, and of those who get tested, most have negative results. Even when the results are negative, doctors often prescribe medication as a prophylactic. When the results are positive, the long incubation period makes it more likely that the hiker picked up the bug somewhere else, perhaps by changing a diaper or swimming in a public pool. A meta-analysis of the literature in 2000 concluded that "the evidence for an association between drinking backcountry water and acquiring giardiasis is minimal."[Welch 2000]"
-
07-02-2013, 09:33 AM #29
I've been using Potable Aqua--chlorine dioxide, same stuff as Aquamira. While the instructions say to wait 4 hours, that is only because that's how long it takes to kill stuff like amoeba and giardia. Bacteria are killed within minutes. You can get rid of the protozoans with a prefilter. I don't recall what micron size is necessary and the one I have doesn't have a name on it. It screws into the top of your standard water bottle. The chlorine dioxide tablets do have some taste IMO but not nearly as bad as iodine.
I have no independent knowledge about giardia and other parasites but I heard the same thing about the lack of Giardia in the Sierra at a Wilderness Medicine course-although the speaker gave the standard advice about treating for giardia he referenced a UCDavis doc who had researched the subject and felt it wasn't necesssary. The prefilter is so easy that I use it.
-
07-02-2013, 10:12 AM #30
I always thought it was weird that people will drink water out of the tap without a second thought but when they come upon a crystal clear, sparkling stream at 10k their first thought is to put bleach or iodine it.
"In a perfect world I'd have all 10 fingers on my left hand, so I could just use my right hand for punching."
-
07-02-2013, 10:27 AM #31Hugh Conway Guest
-
07-02-2013, 10:27 AM #32
No, not really. Having dysentery is not fun.
I overestimated the intelligence of the TGR maggunity, so I'll explain: I contracted the amoeba in 1976 from a Kentucky from a roadside artesian well, i.e., the equivalent of a third world country water source. I contracted giardia in 1983 from a stream below a popular subalpine lake, a place that gets traffic from dumbfucks who don't understand how to shit in the wilderness.
Lesson: (1) treat or filter water in: (a) third world countries, including Kentucky; and (b) water sources that are at risk of getting contaminated by goomba weekend backpacker shit, e.g., lakes near trails, runoff streams from lakes near trails, streams near trails. (2) don't bother treating water where there is virtually no risk that the source has been contaminated by people shit (or beaver shit), i.e., 95%+ of my mountain travel. Had I followed that rule in 1976 and 1983, I wouldn't have had those IT bug issues. Following that rule has worked, i.e., no IT bugs in 29 years and 1500+ days of mountain travel. Get it now?
Yup, it doesn't make much sense. The vast majority of giardia ingestion in the U.S. is from well water or tap water.Last edited by Big Steve; 07-02-2013 at 10:40 AM.
-
07-02-2013, 10:30 AM #33Hugh Conway Guest
We'll never get, that's why you are here to enlighten us in the ways of Wilderness Big Steve.
-
07-02-2013, 10:31 AM #34
-
07-02-2013, 10:34 AM #35
-
07-02-2013, 10:41 AM #36
Don't be so serious, dood
-
07-02-2013, 10:43 AM #37Hugh Conway Guest
-
07-02-2013, 11:20 AM #38glocal
- Join Date
- May 2002
- Posts
- 33,440
It's the runny streak on his sash....
-
07-02-2013, 11:42 AM #39
-
07-02-2013, 02:32 PM #40
Backpacking in the Wind Rivers I came upon a tiny meadow along the edge of a stream--I don't remember the spot but it was obscure enough that I hadn't seen a human all day. The meadow was dotted with small rocks. Under each rock was a turd. I left. Same thing in the Sierra on the edge of Sapphire Lake, my favorite spot in the Sierra. I'll drink untreated water above the highest obvious campsite.
Don't make too much about the stats on Giardia BTW--there are plenty of bacteria and viruses that will make you sick.
-
07-02-2013, 05:58 PM #41
OP, are you planning on any international travel soon where you're worried about waterborne viruses? If not, you don't need a purifier--e.g. the First Need or Steripen. Steripen is cool to kill bacteria and cysts though. If you are planning such travel, then you need more than a filter.
I have a Pur Hiker (filter) that's like 12 years old. Works.
If I was buying now, I'd probably get a Steripen, and carry some iodine tabs for backup. Not because I need it to kill everything, but because it's convenient. My understanding is that they've solved most of the issues they've had in the past. I also drink straight from the source above certain elevations and in certain areas.
-
07-02-2013, 07:46 PM #42
From the Advance Chemicals website, they make the stuff: Pristine works by activating chlorine dioxide, which releases oxygen in a highly active form into the water. When the oxygen is released it kills viruses, bacteria, and protozoa, such as giardia and cryptosporidium.
Water treated with chlorine and iodine is known to be harmful to our health, while often creating foul tastes and odours. Pristine's unique process can actually improve the taste of drinking water. Although using a water filter might seem like a quick fix for purifying water, water filters do not remove all bacteria and viruses. Even the most expensive water filter cannot accomplish what Pristine will do in a short period of time.
The FAQ page is here. I have more detailed info on this somewhere at work, I had to provide backup to a client that needed to placate the health inspector.
And it really does make water taste better. And no, I'm not on their payroll, I just think it is a great product."... Enjoy yourselves, keep your brain in your head and your head firmly attached to your body, the body active and alive, and I promise you this much: I promise you this one sweet victory over our enemies, over those deskbound people with their hearts in a safe deposit box and their eyes hypnotized by desk calculators. I promise you this: you will outlive the bastards." – Edward Abbey
Support Hinterlandian backcountry skiing: wwhsta.org
-
07-03-2013, 06:48 AM #43Registered User
- Join Date
- Nov 2007
- Location
- So. VT
- Posts
- 2,829
-
07-03-2013, 07:31 AM #44
As I said in an earlier post, while it kills everything, it takes much longer to kill the protozoa. However, the protozoa are much bigger and will be trapped by a prefilter with pores big enough to allow water to flow through easily, without a pump. The bacteria and viruses pass through the prefilter but are killed quickly by the chemical.
-
07-03-2013, 09:40 AM #45one of those sickos
- Join Date
- Oct 2005
- Location
- Tahoe-ish
- Posts
- 3,148
I have used Iodine (mostly in Polar Pure form) for hundreds and hundreds of days. Wife and I used it to treat all of our water for 5 months in SE Asia a few years ago. I've also used various filters and other methods.
Frankly I can't see why everyone doesn't just use Iodine. It's easy, cheap, fast, portable, reliable, has a long shelf life, and kills everything. What's the downside, aside from the taste, which I get used to quickly? What am I missing?ride bikes, climb, ski, travel, cook, work to fund former, repeat.
-
07-03-2013, 09:42 AM #46Registered User
- Join Date
- Oct 2008
- Location
- RM trench
- Posts
- 1,969
doesn't iodine make you impotent?
-
07-03-2013, 09:43 AM #47Hugh Conway Guest
Waiting for 20 minutes isn't actually fast? Tastes like ass?
-
07-03-2013, 10:08 AM #48
-
07-03-2013, 11:34 AM #49
Iodine taste can be neutralized with vitamin C, to be added after the iodine has sufficient time to kill bugs. Works quite well, i.e., tastes like untreated water. The two-part neutralizing pills are a ripoff. Much cheaper to whittle off a bit of a vitamin C pill.
-
07-03-2013, 05:40 PM #50
Note on steripens- This is my go-to treatment method for the Sierra Nevada. However, my buddies and I have found the optical version (with an LED sensor) to be more reliable than the dielectric version (metal sensors). It can be a bit finicky at times, but I've never had major issues with it. Much prefer it to any filter system I have ever used, although some of the newer squeeze type ones look pretty nice. I usually carry a few chemical pills as a back-up. Chemicals suck for mountain water because it's usually cold, which means effective treatment times are especially long. Also, drinking cold mountain stream water on a hot summer day is super refreshing.
As far as poop-sanitation- whenever anyone goes to take a crap, hit them up with a shot of hand sanitizer when they get done, before they touch anything else. Works even better if you can convince people to wipe naturally and not haul around bags of bacterial paper.
Bookmarks