How long does water stay 'fresh' in the bottle?

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Martyn

Bushcrafter through and through
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Or until a sufficiently harmful substance enters the water in sufficient quantity to cause harm. Many plastics for example will permit many substances to diffuse through them, so if you were to store a plastic container full of water in your garage next to a plastic can of petrol you might find that the petrol taints the water quite quickly. Also many plastics contain harmful substances which can leach out of the container into the contents over long periods of time. Polycarbonates were famous for that quite recently.
But that is not a problem with the water, it's a problem with the container. You are absolutely right, some plastics will leech and some will break down, but assuming you have a magic container that will maintain a sterile seal for eternity, the water inside will be good for eternity also. Pure water is a mixture of two elements and doesnt go bad - ever. ;)



It doesn't. It just helps things grow that are already in the water if it isn't sterile. Green algae being amongst the most obvious, because they're, er, green. :)
Again, not a problem with the water, but stuff that is in it. It might stimulate the growth of algae, but that is a much less common contaminant than bacteria and viruses, both of which are destroyed by ultraviolet light. Also, it might be green (so is cabbage), but is algae actually harmful? I think most species are non-toxic. In any event, sterilise your containers and boil the water before you fill them and nothing will grow. The only issue is whether the container itself is broken down by UV, but again, that is a container problem. Just get the right container. I believe the reason the NATO water bottle is opaque, is not to stop things growing, but because iodine is broken down by UV which stops it working as a sterilising agent. So if you plan on using iodine to sterilise your water, you need a UV opaque container (or mix and keep it in a dark place until the iodine has done it's job).

All correct. Strong enough sunlight will kill anything. However the Earth's atmosphere filters the sunlight very effectively (otherwise we'd all be dead already) and the sunlight needs to be sufficiently strong that it will kill the organisms in the water, rather than promote their growth. We could probably do with more of that sort of sunlight in the UK. :)
A week in good, direct summer sunshine should kill pretty much all water pathogens. Probably not enough UV in the winter to do the job, but the only real harm is from UV breaking down the plastic and if it's strong enough to do that, it's strong enough to kill the bugs. Bacteria and viruses do not require sunlight to grow BTW, they usually prefer the dark.

This is one subject I do know about mate, I used to work in a public health laboratory as a medical microbiology technician. It was about 16 years ago and I'm not a world expert or anything, but I've got a clue. I spent 6 months in my own private hell, a department called "Milks & Waters". An unbelievably boring job where I tested milk & water samples for pathogens. :)
 
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santaman2000

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Jan 15, 2011
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...Again, not a problem with the water, but stuff that is in it. It might stimulate the growth of algae, but that is a much less common contaminant than bacteria and viruses, both of which are destroyed by ultraviolet light. Also, it might be green (so is cabbage), but is algae actually harmful? I think most species are non-toxic...

I think you're right; about the green ones anyway. Red algae are another matter though. That's what "Red Tide" acyually is; a red algae. Whenever it appears (a coule of times a year here) seafood harvests are suspended as it also poisone the sea life and the toxins enter the food-chain. also people are advised to avoid the beaches as respiratory problems go up.
 

Martyn

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I think you're right; about the green ones anyway. Red algae are another matter though. That's what "Red Tide" acyually is; a red algae. Whenever it appears (a coule of times a year here) seafood harvests are suspended as it also poisone the sea life and the toxins enter the food-chain. also people are advised to avoid the beaches as respiratory problems go up.

Yeah, I've seen algae blooms, but they are an overgrowth of a specific species when conditions are just right for them. I think it's because we are taught to avoid algae blooms, that there is an assumption that all algae is harmful, but I'm pretty sure that the species which cause the blooms are in the minority.
 

maddave

Full Member
Jan 2, 2004
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There's a good reason why military canteens and water jerricans are black. Clean water stays pretty much ok if in the dark. I've had 20ltrs in the van for weeks at a time and it's been fine.

In one of these......

1207251-WATER-JERRY-CAN-20-LTR.jpg
 

bilmo-p5

Bushcrafter through and through
Jul 5, 2010
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There's a good reason why military canteens and water jerricans are black. Clean water stays pretty much ok if in the dark. I've had 20ltrs in the van for weeks at a time and it's been fine.

In one of these......

1207251-WATER-JERRY-CAN-20-LTR.jpg

State-of-the-art water storage, These were the usual method of storing water in ships' lifeboats for donkeys years. The water was routinely changed every 6 months whether it needed to be or not. We used to taste it when doing the changes and it was always sweet.
 

Martyn

Bushcrafter through and through
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There's a good reason why military canteens and water jerricans are black. Clean water stays pretty much ok if in the dark. I've had 20ltrs in the van for weeks at a time and it's been fine.

NATO bottles are made of HDPE, which is tough and cheap - well cheap so long as you dont want a see-through one, but it does leech and does break down faster in sunlight. So one of the reasons the plastic is black, is that it slows down the degradation of the container itself. I think the main reason though, is that the black bottles protect the sterilizing chemicals from UV degradation. Most sterilizing agents break down under UV, iodine is particularly sensitive. If the military needed to issue water treatment, additives, medicines or drugs to it's troops via their water, they would want to be sure those drugs wont break down in sunlight. Keeping water in the dark doesnt keep it any fresher than daylight, otherwise all the Evian and Buxton mineral water on the shelves at Tescos, would be in black bottles and that has a (conservative) shelf life running to years. But keeping it out of sunlight will prevent UV from degrading the bottle itself.

Whatever container you use, clean the bottle first with Milton to sterilise it and then used cold, boiled water and it'll be good for ...well, as long as might need it for, but it'll be years not days.

Yes, UV could stimulate algae because algae is like a plant in that it photosynthesises, but if your water is contaminated with algae, it'll almost certainly be contaminated with bacteria and that would worry me much more. Algae growth could actually be a useful indicator that the water is contaminated. If it was in a black bottle, it would stop algae growing but it wouldn't stop bacterial growth.

So if bottled water doesnt go bad, why does it have a best before date? Well most countries require that everything made for human consumption has a best before date, but also because the water will absorb some chemicals from the bottle over (a very long) time and the taste of the water will change.
 
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santaman2000

M.A.B (Mad About Bushcraft)
Jan 15, 2011
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...So if bottled water doesnt go bad, why does it have a best before date? Well most countries require that everything made for human consumption has a best before date, but also because the water will absorb some chemicals from the bottle over (a very long) time and the taste of the water will change.

The taste will change regardless of the container. The water loses it's loose oxygen and begins to taste stale (the same thing is true of freshly boiled water. But you're right in that it will also pick up the tase of it's container. Just as ice also picks up the smells and tastes of other foods in the freezer.
 

Martyn

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The taste will change regardless of the container. The water loses it's loose oxygen and begins to taste stale (the same thing is true of freshly boiled water. But you're right in that it will also pick up the tase of it's container. Just as ice also picks up the smells and tastes of other foods in the freezer.

Agreed. The point being, that aside from maybe a stale taste and maybe a bit of a plastic taste, commercial bottled water should be drinkable for as long as the bottle remains sealed, which could be a very, very, very long time.
 

Beardy

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Nov 28, 2010
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Re leaching, I thought HDPE (as in NATO waterbottles and jerrycans) was considered safe?

All of the controversy in the past few years has been about Bisphenol A, but is there another danger with HDPE we need to be aware of?
 

SMOKOE

Forager
Mar 9, 2007
179
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Stoke-on-Trent, Staffs
I Know it's not quite relevant to the topic but its a good poem anyway


'E would dot an' carry one
Till the longest day was done;
An' 'e didn't seem to know the use o' fear.
If we charged or broke or cut,
You could bet your bloomin' nut,
'E'd be waitin' fifty paces right flank rear.
With 'is mussick on 'is back,
'E would skip with our attack,
An' watch us till the bugles made "Retire",
An' for all 'is dirty 'ide
'E was white, clear white, inside
When 'e went to tend the wounded under fire!
It was "Din! Din! Din!"
With the bullets kickin' dust-spots on the green.
When the cartridges ran out,
You could hear the front-files shout,
"Hi! ammunition-mules an' Gunga Din!"

I shan't forgit the night
When I dropped be'ind the fight
With a bullet where my belt-plate should 'a' been.
I was chokin' mad with thirst,
An' the man that spied me first
Was our good old grinnin', gruntin' Gunga Din.
'E lifted up my 'ead,
An' he plugged me where I bled,
An' 'e guv me 'arf-a-pint o' water-green:
It was crawlin' and it stunk,
But of all the drinks I've drunk,
I'm gratefullest to one from Gunga Din.
It was "Din! Din! Din!
'Ere's a beggar with a bullet through 'is spleen;
'E's chawin' up the ground,
An' 'e's kickin' all around:
For Gawd's sake git the water, Gunga Din!"

'E carried me away
To where a dooli lay,
An' a bullet come an' drilled the beggar clean.
'E put me safe inside,
An' just before 'e died,
"I 'ope you liked your drink", sez Gunga Din.
So I'll meet 'im later on
At the place where 'e is gone --
Where it's always double drill and no canteen;
'E'll be squattin' on the coals
Givin' drink to poor damned souls,
An' I'll get a swig in hell from Gunga Din!
Yes, Din! Din! Din!
You Lazarushian-leather Gunga Din!
Though I've belted you and flayed you,
By the livin' Gawd that made you,
You're a better man than I am, Gunga Din!

Rudyard Kipling
 

wingstoo

Bushcrafter (boy, I've got a lot to say!)
May 12, 2005
2,274
40
South Marches
Re leaching, I thought HDPE (as in NATO waterbottles and jerrycans) was considered safe?

All of the controversy in the past few years has been about Bisphenol A, but is there another danger with HDPE we need to be aware of?

I hope not, most peoples water supply pipes are made of HDPE, the blue poly-pipe that the water boards and plumbers use to get water from the river, to the treatment works and then to your house.
 

Miyagi

Bushcrafter (boy, I've got a lot to say!)
Aug 6, 2008
2,298
5
South Queensferry
I keep 2 litre PET bottles full of water in the loft just in case we lose the supply. There are fifty or so up there at the moment. Many of them have been there for years.

Later on today I'll get one down for you and drink it. :)

Your ceilings are going to collapse!

When Milton Bridge Camp was being refurbed the false ceilings in some of the billets collapsed - squaddies had been putting empty cans, pint glasses etc in them by moving the polystyrene tiles aside.

How'd the water taste?

Liam
 

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