I don't doubt there's some truth that you heard this. I can't see it making any sense. I stand by my post, above: don't recycle bodily wastes!

In "Survival - How To Prevail In Hostile Environments" by Xavier Maniguet, the author states that diluting fresh water with some sea water or alternating between drinking fresh water and sea water can extend your supply.

He also states that while drinking sea water may not extend your total survival time, it would allow you to remain concious longer and able to gather water in other ways.

I have no idea if this is true. Doug says on the "Books" page that this theory and maybe some others are not widely shared, which seems true enough <img src="/images/graemlins/smile.gif" alt="" />

I received this book years ago before I was ever even interested in this kind of thing. I can type out a few paragraphs of the relevant sections if that's OK and if anyone is interested.

If you post a few paragraphs please give full ISBN title, publisher and author with due credit. There is a minority view in the body of literature advocating various sea water strategems. I think Naro's excellent post 'flushes' the urine idea. I am personally very much opposed to the seawater trick. You must understand that ingesting salt beyond very tight metabolic parameters initiates rather nasty and terminal effects. In a survival situation the discipline to ration intake will quickly fall apart. A friend in the Coast Guard told me about a Haitian refugee he rescued only to watch die an agonizing death from drinking seawater. If I go near the water a reverse osmosis pump in my boat kit is de riguer and my water stores on terrra firma are rediculous overkill. As in everything else, an ounce of prevention averts a gallon of- saltwater or urine <img src="/images/graemlins/grin.gif" alt="" />

Extend it how far? Hours, days?

The human body, unlike some of our seabird friends and certain other species of animals, cannot concentrate salts and excrete them from our bodies in significant life-sustaining amounts. Yes, we do sweat and sweat does contain salts, but in relatively minimal amounts when compared to seawater. Always keep in mind the simple fact that via osmosis (there are several threads regarding this) that water will move across a semi-permeable membrane, from lower salt (hypotonic) solution to the higher or more concentrated (hypertonic) solution, attempting to equalize the concentrations. The purpose of the osmosis is to try and achieve the isotonic state, which is where the body is able to carry out it’s normal functions.

Drinking any concentrated solution (seawater, urine, concentrated electrolytic solutions i.e. GoLytely, Colyte and NuLytely – what you drink before a colonoscopy to induce profuse cleansing of the colon) will cause water to leave the intravascular space (within the blood stream) and by osmosis, travel across the intestinal wall into the colon, where it will be excreted. If excessive in nature or if fluids (water) are not available to replace lost fluids, dehydration will occur.

Bottom line – DO NOT DRINK SEAWATER - period
Pete

What about seawater as an enema? I seem to recall that Dougal Robertsons' family used that method for hydration during their ordeal and in fact Doug recommends such a kit for inclusion in an abandon ship bag. On the surface it would seem to set the same conditions as oral ingestion or am I missing something?
Ed

The author includes a pair of graphs on page 141. His claim is that while a person not drinking water loses conciousness around the 4th day, a person drinking seawater would lose conciousness around the seventh day. In both cases, a person would die around the ninth day.

The author states that "Recent experiments" show that seawater can be consumed that way. He references a "Naufragé volontaire" by Alain Bombard as a source.

I'm quite skeptical of this drinking sea water stuff, too.

Since I do not have the book, I do not know how such an experiment could have or would have been conducted or if it is based only upon anecdotal information, it is therefore, hard for me to comment on the graph.

What I will say is, if this was a truly controlled experiment, I question the ethics of individuals drinking seawater to the point of unconsciousness. If the graph describes anecdotal cases (different individuals under varying circumstances) and bases the conclusions upon that information, it is like comparing apples to oranges. Each individual will respond differently, depending upon gender, age, physical conditioning and pre-existing medical conditions.

Pete

It sounds counter productive for the prevention of dehydration, as to why one would want to bring on the affects of an enema. By it’s very nature, an enema, without fluid replacement would hasten dehydration.

Now if the recommendation is, substituting seawater for some of the more common enema solutions, then yes, seawater would likely work, but so will soapy water.

If using seawater as a substitute of traditional enema solutions, just be sure an enema is medically necessary and adequate fluid replacement is available. Also, seawater is not/may not be a biologically clean solution. Vibrio cholerae is known to infect shellfish and can be cultured from seawater containing such shellfish.

Perhaps one of the physicians on the forum could comment.

Pete

It's been a long time since I read his book, but I don't think the Robertsons used plain seawater. Rather, I believe that some of their freshwater was partially contaminated with seawater and residue from the rubber sheet that they were using to catch rainwater. That is what they used via enema. It was so diluted that it posed no danger. It's a great book. I guess I'll have to get it and read it again. <img src="/images/graemlins/smile.gif" alt="" />

Regards, Vince

You might be correct. It's been a long time since I read that book myself and the specifics elude me. That seems to happen more & more frequently these days <img src="/images/graemlins/frown.gif" alt="" /> Maybe a trip to the library is in order.