Ro Water - Safe From Human Consumption?

[CFC]

POI: The majority of the minerals that we receive in our body is from our diet and NOT from our water. SH

yes and as the Surgeon Generals report states a vast percentage of US citizens, are not getting enough calcium, from that diet! drinking water that will make you excrete even more, of the stuff, seems to be the wrong thing to do. it is even more important if you live in warmer climates.

Can i clear something up here?
All manufacturers of drinking water RO units, insist that the water supply must be "safe" before the RO unit can be used so aside from removing nitrates, as this is the only thing a RO unit does that other filtration systems cant. and after factoring in the ludicrous amount of water wasted by these units, just what is the point of having one?

They are used mainly in laboratories to produce pure water for diluting chemicals and other bits and bobs (i'm sure someone more sciency than me can tell you what they use them for better), the cleaning industry also uses them a lot to provide easy streak free cleaning on shiny surfaces, and of course anyone with a marine tank or delicate softwater fish will need one to provide the right water for their fish. Its just some health freaks that have started the using them for drinking water nonsense, i dont even bother replacing the filter on our fridge water dispencer because the filtered water tastes nasty and R/O is even worse, reminded me of the awful water in Wales we had to drink while on a school trip many years ago, thankgod for bottled mineral water these days.

 

[raptorrex]

They are used mainly in laboratories to produce pure water for diluting chemicals and other bits and bobs (i'm sure someone more sciency than me can tell you what they use them for better), the cleaning industry also uses them a lot to provide easy streak free cleaning on shiny surfaces, and of course anyone with a marine tank or delicate softwater fish will need one to provide the right water for their fish. Its just some health freaks that have started the using them for drinking water nonsense, i dont even bother replacing the filter on our fridge water dispencer because the filtered water tastes nasty and R/O is even worse, reminded me of the awful water in Wales we had to drink while on a school trip many years ago, thankgod for bottled mineral water these days.

thanks CFC, sorry, i did mean for drinking water supply's.

 

[Colin_T]

How about desalination units used by governments to provide their citizens with drinking water. If the governments didn't think it was safe for human consumption would they make everyone drink it. If it wasn't safe people would eventually find out and that would be the end of the government and its desal plants.
Desalination plants are used all over the world to provide a source of fresh water. see Wikipedia.

 

[Bignose]

How about desalination units used by governments to provide their citizens with drinking water. If the governments didn't think it was safe for human consumption would they make everyone drink it. If it wasn't safe people would eventually find out and that would be the end of the government and its desal plants.
Desalination plants are used all over the world to provide a source of fresh water. see Wikipedia.

Colin, if you had actually read the WHO document (how many times have I written that now?), there are recommendations for both the maximum and minimum TDS in the water. The desalination plants take the salt out of the water and then add in calcium and magnesium. They don't send it out completely demineralied.

By the way, any chance that you're going to back up some of the statements you made above? (I'm getting tired of asking.) Specifically, the ones about chlorine in the water causing cancer?

 

[Bignose]

While waiting for my computer codes to run, I've been poking around and looking into a few more of these things.

I've found the mechanism by which demineralized water causes a cascade of effects that results in net mineral loss by the body. Hopefully this will satisfy Musho.

"The excess sodium in the gut increases blood sodium levels and pulls water from
intracellular fluid into the bloodstream. This increased volume then raises levels of atrial
natriuretic peptide, decreases formation of angiotensin II, and decreases aldosterone
secretions by the adrenal cortex. These three responses cause a greater loss of sodium
and chloride ions and water through the kidneys into the urine in order to reduce blood
volume. This cascade of homeostatic control was designed to take into account different
levels of electrolyte intake, and works well, especially for elevated intakes. However,
when no sodium was initially taken in, yet more was excreted this creates a problem that
has to be re-corrected, which the body happily does, though not perfectly. So, there is
some hard data showing that there are extra losses of minerals as a result a drinking low
mineral water. In spite of these homeostatic controls, minerals really can be removed
from the body by distilled water. This is a major finding, because advocates of distilled
water claim that the minerals in the body are protected in some way from being taken out
by distilled water. It is a nice idea, but these animal and human studies argue that it
really doesn’t work that way."

There is also a chart: (I'm just going to type out the steps here rather than try to copy the chart, the format here is that 1 causes 2, 2 causes 3, etc)

1) Low mineral water causes osmosis of Na+ into the gut lumen
2) Increased plasma concentration of Na+
3) Increased osmosis of water from inside cells into plasma
4) Increased blood volume (this causes 2 things to happen 5a & 5b)
5a) Increases stretching of atria of heart
5b) Decreased formation of angiotensin II (causes two things 6b1 & 6b2)
6a) Increased release of atrial natriuretic peptide (caused by 5a)
6b1) Increased glomerular filtration rate
6b2) Decreased release of aldosterone

Now all three effects listed in 6 contribute to effect number 7

7) Reduced reabsorption of NaCl by kidneys
8) Increased loss of Na+ and Cl- in urine,
along with other minerals
9) Increased loss of water in urine by osmosis
10) Decreased blood volume

This was taken from a recent human physiology text: Tortora and Grabowksi, Principles of Anatomy and Physiology 9th ed. John Wiley & Sons, Inc. 2000

I hope that this is what you were looking for Musho.

 

[steelhealr]

Bignose..yes...these are the normal hormonal actions of the human to maintain homeostasis. Without saying this in a negative way (hard to do on a PC), the way it is presented sounds 'abnormal' or harmful'. The reverse can occur if you eat a salt bagel or salty pretzel. This is the way the body keeps us steady. If we have one glass of RO water, this may or may not happen depending on what you are eating. If you wash down a dee-licious NYC pretzel fresh off the coals..then wash it down with an ice cold glass of RO water...you could potentially see NO action at all.

EG: 1) SH, a NY'er...eats a deelicious NYC salty pretzel..let's just say without water
2) Heavier load of Na+ and Cl- enters the GI system
3) Increase in Na+ absorption into the gut and pehaps some efflux of water into the lumen
4)Normal serum sodium is about 135-145...let's just say my sodium climbs to 148
5) Osmoreceptors in the brain release ADH (antidiuretic hormone) causing the body to whole onto water (lowers Na+)
6) Increased plasma Na+ may increase BP (why people who are hypertensive eat reduced sodium diets), increasing those stretch receptors of yours thus
7) Increasing aldosterone by the adrenal cortex causing increased Na+ ion exretion in the distal collecting tubule in the kidney and aldosterone MAY have a secondary effect by stimulating ADH release by the posterior pituitary

And we haven't even touched on renin.

All in reaction to eating a dee-licious salty bagel. I placed this NOT to debunk what you wrote, but, as you described it...these are standard bodily reactions on a DAILY basis to what we eat.

SH

 

[Bignose]

Sure, sure. But, Musho wanted to know the processes that lead to increased minerals in the urine. I have to admit that I only have a vague idea of what most of those terms mean, physiology is not my subject. But, I was trying to show Musho that the "how" is out there. It wasn't my intent to make it read harmful, it is exactly as I copied out of a book.

 

[steelhealr]

SH