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Peaks
06-06-2003, 07:37
The article, entitled "Germs can lurk in water bottles", ran in Tuesday's
Boston Globe, in the Science / Health section. You can find it in its
entirety at
http://www.boston.com/dailyglobe2/154/science/Germs_can_lurk_in_water_bottle
s+.shtml.


I especially liked the practical suggestions at the end, to wit:


"For hikers, [Ryan] Jordan[, a researcher at Montana State University's
Center for Biofilm Engineering,] recommends these 'best practices.' To
gather water, find a spot where you do not disturb the sediment, submerge
your closed water bottle, open it under the surface, and let water flow in
from the middle of the water column. Close the bottle underwater and lift it
out. That way, you start with biofilm-free water, which you can filter for
drinking. [Biofilm: "the coating on rocks and sediment at the bottom of
streams and ponds, as well as the thin surface film on standing water."
It's laden with microbes.]


"To prevent biofilms from growing on the filter, [which they often do,]
back-flush the filter every few days to wash out the bacteria. Scrubbing the
filter's outer element with a toothbrush is even more effective.


"Jordan himself doesn't use filters. He relies on chlorine dioxide drops,
which unlike iodine pills can kill giardia and cryptosporidium even in
biofilms. (Chlorine dioxide has long been used in municipal water treatment,
but is a relatively new product for back-country use.)


"Surprisingly, the primary route of intestinal infection on the trail is not
water, Jordan said, but rather the link between not washing hands after
going to the bathroom, and handling food. He recommends alcohol hand gels
rather than soap: 'Soap is too impractical to use properly and alcohol gels
kill fecal bacteria more effectively.'


"Back-country dishwashing can become very elaborate, but Jordan has these
suggestions: Don't wash dishes! Just wipe them clean and dry them out.
Bacteria can't live long on a dry surface, and putting them in the sun for
an hour will disinfect them. Boiling water for your next freeze-dried meal
will sterilize anything that's left in the cooking pot.


"All the more time to lie back and enjoy the stars -- or whatever brought
you so far from indoor plumbing to begin with."

Chef
10-29-2003, 02:34
So I have a question which treatment I will use for the at. I am not bringing a filter most likely, weight issue. I dont mind iodine that much, but i am unsure of how safe it is to use for up to 6 months? I hiked with my friends this past summer on the LT and they were using regular clorox bleach. Its much cheaper, doesn't taste as bad, but is it as effective and how safe ? Also what are your views on carrying a filter?

dionalaniz
10-29-2003, 04:11
I'm carrying a filter on my hike. But when the temperature plummets, rendering my filter useless, i'll rely on bleach. I was a bit sketchy about the idea of using regular chlorox bleach but i've seen many people on this forum recommend its use and i've found that the Red Cross itself recommends the use of regular household clorox bleach for water treatment during a crisis. So, sounds good to me.

Now, if my little 1 oz. bottle of clorox freezes solid then, gadzooks! :-)

MadAussieInLondon
10-29-2003, 04:37
i have a filtre with aqua mirra backup if needed.

Blue Jay
10-29-2003, 08:51
Bleach does not work and in fact will harm your stomach more than Giardia. I'd say stop being so cheap and buy decent water treatment chemicals, but it's your health. I'd go without any treatment at all before I'd use bleach.

deeddawg
10-29-2003, 09:30
Originally posted by dionalaniz
[...] and i've found that the Red Cross itself recommends the use of regular household clorox bleach for water treatment during a crisis. So, sounds good to me.

I recommend doing further reasearch -- I believe you'll find that bleach is recommended more for sanitizing objects and as a "if you have no other way" means of water treatment. There are much more effective treatment methods that really don't cost much; especially when you factor in the potential cost of getting medical treatment for something the bleach didn't kill or inactivate.

Do a search here on "bleach" and you'll find TONS of information; some accurate, some not so accurate. Follow referenced links to the source documents and then follow up from there.

Personally I'd use bleach only if there was no other means available to me. Sodium hypochlorite (bleach) behaves differently from chlorine dioxide (Aqua Mira) despite both having chlorine.

One particular paper of interest is here:
http://aem.asm.org/cgi/content/full/68/5/2576

What I gather from that paper is that Crypto shrugs off full-strength bleach (5-6% sodium hypochlorite); I'm not real sure that a few drops of bleach are going to do anything to it.

Now with that said, there are folks who treat their water with bleach. But that does not mean that bleach necessarily kills any bugs. They may be more skilled and careful about their choice of water supply. They might have gotten lucky. They might already have developed an immunity to the bugs bleach doesn't kill. Some sources indicate that even when drinking water contaminated with Giardia, many people will not be infected, and a number of those who actually do become infected do not show any symptoms. For those reasons I don't think you can accurately claim that treating with bleach will keep you from getting sick; there are too many other factors involved to establish a true causal relationship between treating with bleach and not getting sick.

Along similar lines, there are folks who use filters who DO get sick; does that mean the filters don't work? Not really; it has been suggested that the most likely cause of intestinal illnesses on the trail are from sources related more to personal hygine than water.

What it all boils down to though is that IMHO the two most important things to avoid getting sick are to be careful about hygine and be careful about your water sources. If a water source is questionable, use the most effective treatment available.

Panzer1
05-29-2006, 15:25
I'm carrying a filter on my hike. But when the temperature plummets, rendering my filter useless, i'll rely on bleach. I was a bit sketchy about the idea of using regular chlorox bleach but i've seen many people on this forum recommend its use and i've found that the Red Cross itself recommends the use of regular household clorox bleach for water treatment during a crisis. So, sounds good to me.

Now, if my little 1 oz. bottle of clorox freezes solid then, gadzooks! :-)

Of all the ways you can treat water, bleach is the last choice. I'm not saying it dosen't work, just that every other method of treating water is better than bleach.

The reason why the Red Cross uses bleach in a crisis is because there is nothing else available to a large segment of the population in a crisis. Almost everyone has bleach in their house. AT hikers do not fall into the "crisis" category. You have plenty of time to plan and pick a better method. Some problems with bleach is 1) it is unstable, even more unstable in heat. 2) The concentration diminishes over time. 3) you have no way of knowing how long the bleach has been laying around. 4) You don't know the concentration when it was made.

People flock to bleach because it is cheap, and AT hikers are cheap too. Hence the attraction. My advice: don't be cheap, spend some money and get something good.

Panzer