Blood pressure myth?


LifeTime Supporter
Apr 26, 2009
A customer of mine who's quite large and has very high BP was looking at an SWCG - until he saw this.

I've never heard of problems with SWCGs (although part of the reasoning makes sense). I tried google to no avail (or at least anything relevant).

Also searched the forums and nothing.

Thoughts and opinions?

- Jeff

"Health and Environmental Concerns
# Human skin that is exposed to saltwater systems will absorb sodium, salt and chlorine. Sodium absorption through the skin has been associated with health concerns and higher heart mortality risks, especially among those with high blood pressure, circulatory issues and a history of stroke. Concerns that saltwater systems damage the environment have led to "Ban the Brine" movements, resulting in their use being discontinued in some areas, including Los Angeles County, California.

Read more: Saltwater Pool Problems | ... z0yQubOZmO"


Well-known member
Jan 27, 2010
Central Valley, CA
I'll say this, living in CA, they are going to try to ban everything but sleeping before you know it and I'm sure they will determine even that causes cancer. Sorry I can't speak to legitimacy of the claims.


LifeTime Supporter
Nov 30, 2008
Sleeping for days on a float in the ocean on a mooring near an island in saltwater at 30,000 ppm - maybe..

A few hours in a swimming pool a week at 3,200 PPM- not likely.

Uncle Dave


TFP Expert
May 20, 2007
South Central NJ
The use of brine tank based water softeners was what was banned. SWCGs were excluded. The body sweats when swimming, losing salt, not absorbing salt.



In The Industry
Jul 25, 2009
London and France
Your skin cells and most other human cells contain a salt level around 7000ppm (from memory) so immersion in any liquid with less than the electrolyte (salt) content of your body results in osmosis (the movement of the high salt level from skin cells into the lower salt level water bath or pool) in an attempt to equalise the salt level to protect skin cells from rupture or collapse. You would only absorb salt if the pool was higher in salt than your skin cells.

Immersion in any liquid raises the blood pressure whether it's salt or normal water, that is why we get the urge to pee, in order to lower the blood pressure level in our bodies so it sounds like the salt argument is just marketing blah blah. If I get a chance I may ask a relative who is a heart specialist unless there is one on the forum.


LifeTime Supporter
May 21, 2010
Southern Indiana
I'll second what teapot posted. Also, here's a thought - perhaps the "article" was referring to full-on saltwater pools - that is, pools that use sea-water for the water supply - or, perhaps the "article" was confusing SWCG pools with salt-water (ie, sea-water) pools- either through ignorance or intentional misrepresentation. Where was this statement published?


Well-known member
Aug 17, 2007
Eastern Canada
I took a look at some of the advertising links at the bottom of the page that was quoted, and found a link to an EcoSmarte page with similar text to what is on the eHow site. I would conclude that this blood pressure myth is being propagated by EcoSmarte, who sell a copper-based sanitization system, and whose sales are undoubtedly being negatively affected by the popularity of SWCGs.

From the EcoSmarte page entitled "Seven Secrets Salt Water Pool Sellers Don't Want You to Know" (
Salt systems are more harmful to human health than conventional chlorine, bromine or bioguanide chemicals.

With a salt system your skin will absorb sodium, salt, AND chlorine, versus just the halogen with a chemical sanitizer such as chlorine or bromine. Sodium absorption through the skin has long been known to present health risks at levels far below the 3000-5000 ppm levels salt chlorine generators require. For nearly 20 years people with high blood pressure, stroke history or other circulatory system issues have been asked to stop using their water softeners (at 200-400 ppm sodium in the water for just ten minutes in the shower) to avoid the heart mortality risks. The chlorine level and skin absorption of the chlorine is still based on the same 1-3 ppm chlorine residuals found, dioxin forms (as do chloramines) and the backwash water contains 3000 ppm or more chlorides.
Although I am not an expert, I would suspect that most of the problems with water softeners affecting blood pressure have more to do with DRINKING the water than with skin absorption. I would also think that swimming in the ocean would be more hazardous than a pool, due to much higher saline concentration, but I have never seen a warning to this effect at a beach!

Conclusion: scare tactics by a competitor to salt water chlorine generators


Well-known member
Sep 27, 2008
Houston, TX
If you follow the links there are some interesting things.
For example, if you follow their link to the LA County salinity act, which also mentions Santa Clarita Valley, reading further everything that is mentioned is Australia? Is LA County and Santa Clarita Valley in Australia?


LifeTime Supporter
May 21, 2010
Southern Indiana
Yes, there are a number of problems with EcoSmarte's information - first, they mention the sodium threat and the 3000 to 5000 ppm level required for SWCG pools in the same sentence, implying there is 3000 to 5000 ppm sodium - the 3000 to 5000 ppm is part sodium, part chloride - not all sodium. Second, as you note derekm, the threat of high sodium levels for people with high BP coming from water softeners is due to consumption, not absorption. There are other issues with EcoSmarte's statements, but suffice it to say, EcoSmarte is losing credibility by spreading that kind of mis-information.


TFP Expert
Apr 15, 2007
Ft Lauderdale, Florida
Osmosis response - perfect. I explain the osmosis effect in my presentations as the reason salt chlorine generators provide that soft water feel vs traditional chlorinated pools without salt in the pool and its drying effects.

Salt ingestion is infact how a salt chlorine generator pool "MAY" affect blood pressure. If this is a real fear, AutoPilot has recommended the use of Potassium Chloride instead. You're still generating chlorine, but the temporary byproduct is potassium instead of sodium. Potassium chloride is commonly used as a food grade salt substitute.

Regarding LA County and Santa Clarita, LA County has several states that have banned all salt related products, primarily due to the amount of salt discharged by water softener systems. Their claim to the ban is that the water ends up in the main river stream that eventually flows downstream to avocado and strawberry farms. Those farms use the river water for irrigation, and they have experienced salt saturation related damage. So to avoid risk to avocado and strawberry crops, they have banned all salt related equipment that are discharged into the city sewer lines.
LA County initially banned salt chlorine generators throughout the county, but recinded that decision 4 months afterwards, and just kept it intact in the cities along the river.

Darkside of the Pool

LifeTime Supporter
Jul 20, 2010
OP: Before I've stumbled on this site, I did have to make a research about which supplemental system to offer our customers, mainly for pools... Ionizers, Ozone, U.V. Rays... I have stumbled on many sources of informations from the industry, but was astonished how much Copypasta was in their work... then suspicion aroused.

As a rule of thumb, if many sources uses the EXACT SAME TEXT, without nuance or even rephrasing or anything, I am wary. Those ''7 things pool stores don't want you to know has became viral''. Also beware their ''satisfied customers''... they sounds like drones of the marketing services.

Sad part is that the CDCs seems to supplement a few of these claims, particularly when it comes to Guardia and Cryptosporidium. I believe they do so to keep matters simple for simple pool owners (K.I.S.S.) and/or they don't test with every variable in (like CYA). [Edit: ''They'' reffered to CDC, unintentional] The less honest parts of the industry also tend to be viral on bans, anything that seems to support them is exploited and mined as much as it can be. This is the case with salinity threats to the environment: How bad is the situation in Australia, where SWCG were born, huh? Well, they tend to forget the fact Australia is a friggin' Island in the pacific to better point out the ''threats'' to the environnement SWCG poses.

But this ''improvised weaponry'' have little effect on anyone able to criticize... that is why we should do our best to inform as many people out there. God, did you know Ecosmarte Spas claimed to be awarded Energy Star?

I have a dream. I dream of the day ''pool stored'' won't be in use... or at least, not the way it is used nowadays...


TFP Expert
Apr 15, 2007
Ft Lauderdale, Florida
ON Australia and SWCGs, Australia has also been much drier than normal the last few years, which will lead to higher levels of ground salinization.

Salt chlorine generators seems to always get the blame though. eh...we're use to it by now.


Gold Supporter
LifeTime Supporter
Sep 9, 2008
The Woodlands, Texas, USA
Osmosis is the transfer of water from a low salinity source to a higher salinity source.

It is possible your body could gain some sodium ions via ion exchange via a semipermeable membrane known as your skin. I would not expect it to be of a sufficient amount to matter.

Now if you drink water from the pool or from a water softner you could ingest significant quantities of sodium.

The other factor is that only some instances of high blood pressure are sensitive to sodium intake. For many sodium intake has no effect. Some people with liver failure are sensitive to sodium intake.

For most healthy individuals a little excess sodium is quickly eliminated in the kidneys. That is what they do: Regulate levels of electrolytes in your body. If you have kidney failure you will be on dialysis in which they do the same thing for you on a machine.

Most cases of high blood pressure can be cured with weight loss.

I love my saltwater pool. No pro lems here.


Well-known member
May 9, 2008
NE Florida
I'm claiming BS on this one. Without actually looking up all the specifics, most salt water systems are maintained at levels similar to human tears, which are consistent with what is called normal saline, 0.9% if I recall correctly. So, you are basically immersed in a solution that is very similar to the saline levels already in your tissues. There should not be a significant net sodium transfer in or out of the body. I'd be more worried about buckling my seat belt on the way to the store than effecting your BP in a Salt water pool.


TFP Expert
LifeTime Supporter
Jul 30, 2010
Twin Cities, MN
My perspective: the percent NaCl in a salt water pool is ~ 3000 ppm and the percent in the human body is ~9000 ppm. In simplified engineer speak :blah: , since the partial pressure of NaCl (or Na+ and Cl-) is higher inside of the body than the partial pressure of NaCl on the outside, if there were a net NaCl transfer through the membrane (skin) separating the two pools of NaCl, it will be net outward. In reality, instead of significant transfer of NaCl, Osmosis will drive water (ion form) through your skin into your body in attempt to balance the partial pressure of NaCl on the inside and outside of your skin much faster than NaCl (or Na+ and Cl-) can permeate through the skin. So in theory if you were to stay in your pool (or any water with a lower concentration of NaCl), eventually the concentration of salt inside the body would actually go down due to dilution but you would be "retaining" more water. Before some of our more weight conscious members get excited about this, you would have to live in a pool for significant weight gain to occur, personally I probably should go live in the sea(~30000 ppm NaCl), to drive out some "excess" I have :mrgreen:...tmi I think :oops:


Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
In The Industry
Apr 1, 2007
Sebring, Florida
I think there is a lot of truth to it. I priced a salt system for my fairly large pool and my blood pressure increased almost immediately :shock: :shock:
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