Health Effects of Brackish Water of Different Concentrations Over Various Lengths of Time?

[CloudsRest]

What are the effects on a human body that consumes brackish water of different NaCl concentrations ranging from 1,500ppm to 30,000ppm? My understanding is 500ppm or higher is considered unsafe, blood and IV fluids are around 9,000ppm, recommended daily sodium allowance is around 2,300mg or 2.3L of water at 1,000ppm, and around 30,000-35,000ppm (sea water) the kidneys can no longer remove salt from the body. It seems that in premodern times, humans often did not have a choice in their water sources and many resorted to drinking brackish water. What's even more interesting is entire settlements were created that relied on brackish water with concentrations around 1,000-2,000ppm, and many domesticated animals still rely on these water sources. What types of health effects would these people have experienced in both the short term and long term, and would the prevalence of these effects increase linearly with the salinity of the water or do issues become compounding?

[exchemist]

25 minutes ago, CloudsRest said:

What are the effects on a human body that consumes brackish water of different NaCl concentrations ranging from 1,500ppm to 30,000ppm? My understanding is 500ppm or higher is considered unsafe, blood and IV fluids are around 9,000ppm, recommended daily sodium allowance is around 2,300mg or 2.3L of water at 1,000ppm, and around 30,000-35,000ppm (sea water) the kidneys can no longer remove salt from the body. It seems that in premodern times, humans often did not have a choice in their water sources and many resorted to drinking brackish water. What's even more interesting is entire settlements were created that relied on brackish water with concentrations around 1,000-2,000ppm, and many domesticated animals still rely on these water sources. What types of health effects would these people have experienced in both the short term and long term, and would the prevalence of these effects increase linearly with the salinity of the water or do issues become compounding?

What settlements were these?

 

[CloudsRest]

11 minutes ago, exchemist said:

What settlements were these?

 

Iosepa in Utah is an example, but there are likely hundreds. I say likely because I haven't driven to the rest to verify. It's located by Horseshoe Springs, a brackish spring around 1,600ppm. This spring was famously used for water along the California Trail at Hastings Cutoff as a last water source before crossing the Great Salt Desert. Iosepa is located in Skull Valley, and the entire valley is full of artesian springs, all of which are brackish. I spent an entire weekend driving around in my Jeep taking measurements. One spring about 20 miles from the settlement was 1,200ppm. The rest were in the ballpark of 1,500-2,000. My understanding is artesian springs come directly from the groundwater (why they're pressurized), so drilling a well wouldn't likely yield fresher water. I've driven all around Utah and Nevada, and brackish water seems to be the norm.

Edited December 26, 2023 by CloudsRest

[exchemist]

7 minutes ago, CloudsRest said:

Iosepa in Utah is an example, but there are likely hundreds. I say likely because I haven't driven to the rest to verify. It's located by Horseshoe Springs, a brackish spring around 1,600ppm. This spring was famously used for water along the California Trail at Hastings Cutoff as a last water source before crossing the Great Salt Desert. Iosepa is located in Skull Valley, and the entire valley is full of artesian springs, all of which are brackish. I spent an entire weekend driving around in my Jeep taking measurements. One spring about 20 miles from the settlement was 1,200ppm. The rest were in the ballpark of 1,500-2,000. My understanding is artesian springs come directly from the groundwater (why they're pressurized), so drilling a well wouldn't likely yield fresher water. I've driven all around Utah and Nevada, and brackish water seems to be the norm.

From this account of its history, Iosepa does not seem to have relied on brackish water. They had intermittents streams and built a reservoir: https://issuu.com/utah10/docs/uhq_volume76_2008_number4/s/10217177 

Edited December 26, 2023 by exchemist

[CloudsRest]

11 minutes ago, exchemist said:

From this account of its history, Iosepa did not rely on brackish water. They had intermittents stream and built a reservoir: https://issuu.com/utah10/docs/uhq_volume76_2008_number4/s/10217177 

The streams they are referring to are still there, as are the reservoirs. They come from the brackish springs I mentioned, and the reservoirs are brackish. That said, I'm not here to debate how people lived. I'm also not asking if anyone should drink brackish water. I'm asking an academic question: what happens to the body when different concentrations of sodium, above what is generally considered safe, are consumed in the form of brackish water. I came here hoping the audience would be more academic-oriented and less contentious than Reddit. Surely there must be someone on the internet with a PhD or at least a Masters in a relevant field who can address this? I can't imagine any quantitative salinity ranges for safe drinking water were ever determined by the medical community without observing the effects of higher concentrations on the body.

Edited December 26, 2023 by CloudsRest

[exchemist]

12 minutes ago, CloudsRest said:

The streams they are referring to are still there, as are the reservoirs. They come from the brackish springs I mentioned, and the reservoirs are brackish. That said, I'm not here to debate how people lived. I'm also not asking if anyone should drink brackish water. I'm asking an academic question: what happens to the body when different concentrations of sodium, above what is generally considered safe, are consumed in the form of brackish water. I came here hoping the audience would be more academic-oriented and less contentious than Reddit. Surely there must be someone on the internet with a PhD or at least a Masters in a relevant field who can address this? I can't imagine any quantitative salinity ranges for safe drinking water were ever determined by the medical community without observing the effects of higher concentrations on the body.

OK. This abstract: https://www.nature.com/articles/s41581-021-00533-0

says that apart from hypertension it had effects on the kidneys (not surprising), brain and immune system. Not clear to me how many of these factors are knock-on effects of hypertension, as opposed to other direct effects of excess sodium. There will be others who know much more about this, e.g. @CharonY