Sea Water for soap.

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In response to @Fiona Robertson's questions about sea water in Zany's No-Slime Castile thread, I thought I would start a thread about this.

Fiona, you state that you are worried about plastic waste on your beach and consequently the amount of pollution/contamination in the water. One of the advantages of living in New Zealand is that we have a small population (only 4 million in a land slightly larger the size of the entire UK) and thus, less pollution.

The beach I go to is by a very small township, and they are a very 'green' community. So before I even collect the sea water, I know it's probably a lot less polluted than the water surrounding the Edinburgh area (nice city BTW - I've been there).

Once collected, I sieve it first to remove anything major, then I boil it for a short time ( about 5 mins max) to remove any impurities. I then pass it though a coffee filter and freeze it once cooled (thanks to @SaltedFig for that idea). I often use small 'snack sized' plastic zip lock bags and label the quantity - smaller quantities are better so you can use one, two or three for a batch of soap. Or you can ice cube them all and store them that way.

Hope that helps. It would be interesting to find out what other people do with their sea water.
 
I am looking forward to learning more about how your soap made with sea water works out, KiwiMoose. I have never collected sea water, but I have lots of kelp that I harvested from the ocean. I use in cooking.

In another state, in the town where one of our former presidents grew up, there are natural mineral water springs that at least one soapmaker sometimes include in soap. From my conversation with the soap maker's staff (in the little soap shop) they used it sometimes, but not very often. Personally, I would suspect the amount of extra minerals in the water would have probably been problematic, and that perhaps she just didn't want to admit that since the mineral waters are big part of the tourist trade there.

While in Alaska two or three years ago, I spoke with a soapmaker in Juneau, Alaska and asked if they ever used glacial water in soap. I actually don't remember if she said yes or no, but they (the family & staff) do use glacial silt about the same as we might use clays or pumice, I guess. I assume the glacial silt contains salt since it is oceanic waters that formed the glaciers. The shop was so busy and the line to purchase so long, I didn't end up buying a soap to take with me. Maybe next time.
 
I haven’t used sea water for soap, but I have thoughts and questions.

1) Why not just make your own salt water with clean, fresh water and salt? Is there some unique quality to sea water?
2) If using sea water, why not process it in a pressure cooker to sterilize it and kill any bacteria/flora/fauna etc?
3) Anybody ever considered making a filter out of activated charcoal like the old middle school science experiment?
 
In response to @Fiona Robertson's questions about sea water in Zany's No-Slime Castile thread, I thought I would start a thread about this.

Fiona, you state that you are worried about plastic waste on your beach and consequently the amount of pollution/contamination in the water. One of the advantages of living in New Zealand is that we have a small population (only 4 million in a land slightly larger the size of the entire UK) and thus, less pollution.

The beach I go to is by a very small township, and they are a very 'green' community. So before I even collect the sea water, I know it's probably a lot less polluted than the water surrounding the Edinburgh area (nice city BTW - I've been there).

Once collected, I sieve it first to remove anything major, then I boil it for a short time ( about 5 mins max) to remove any impurities. I then pass it though a coffee filter and freeze it once cooled (thanks to @SaltedFig for that idea). I often use small 'snack sized' plastic zip lock bags and label the quantity - smaller quantities are better so you can use one, two or three for a batch of soap. Or you can ice cube them all and store them that way.

Hope that helps. It would be interesting to find out what other people do with their sea water.

Yes, this certainly does help, thank you! The next village round the coast from us is out to the open sea and has a beach with blue flag status so I may harvest some sea water from there and give this a go :)
 
I haven’t used sea water for soap, but I have thoughts and questions.

1) Why not just make your own salt water with clean, fresh water and salt? Is there some unique quality to sea water?
2) If using sea water, why not process it in a pressure cooker to sterilize it and kill any bacteria/flora/fauna etc?
3) Anybody ever considered making a filter out of activated charcoal like the old middle school science experiment?

I spent my career studying marine organisms and the sea around then and I can’t keep myself from jumping in on this thread :)

The major salt in the ocean is sodium chloride, but there is also quite a bit of sulfur, magnesium, potassium and calcium. Less concentrated components are bicarbonate, bromide, strontium and fluoride, many other minerals at trace levels and dissolved organic matter that is produced by plants and animals, or washed in from the land or atmosphere. A product called “Instant Ocean” gets close enough to the correct mineral composition to keep aquarium fish happy. Fish and other marine organisms are adapted to the composition of seawater and need to stay in seawater to stay healthy.

Pressure cooking sea water would be a good way to sterilize it. In industry and microbiology labs (and probably in hospitals, too) they use autoclaves to sterilize with steam under pressure.

An activated charcoal filter will take out anything organic, but not the salts, metals, and other inorganic compounds like ammonia and the acids that come down in acid rain (which do not contain carbon). If I was collecting seawater near an urban area I would definitely want to filter twice, first with something like a coffee filter to remove particulates and then with a charcoal filter to remove organic pollutants from car exhaust and industry. If the collection site was near a river mouth that went through farming areas I would first filter to remove fine dirt and bits of land plants and then with a charcoal filter to remove any pesticides and herbicides.

As a sidebar - you can improve the taste of cheaper vodka by running it through a charcoal filter to remove some of the undesirable organic compounds :). You wouldn’t want to do that with gin, which depends on organic compounds from juniper, lemon and florals for flavor and aroma :).
 
One more thing I just thought of - although some bacteria might survive a lye bath, most bacteria that live in ocean water probably would not. For that reason, I probably wouldn’t bother with sterilizing the seawater. There are plenty of bacteria in marine muds that can withstand high pH, low pH and temperature extremes, but they usually would not be found in any quantity up in the water itself.
 
One more thing I just thought of - although some bacteria might survive a lye bath, most bacteria that live in ocean water probably would not. For that reason, I probably wouldn’t bother with sterilizing the seawater. There are plenty of bacteria in marine muds that can withstand high pH, low pH and temperature extremes, but they usually would not be found in any quantity up in the water itself.

Thank you for all the useful info Mobjack Bay. I will give this some thought...might be fun!!
 
One more thing I just thought of - although some bacteria might survive a lye bath, most bacteria that live in ocean water probably would not. For that reason, I probably wouldn’t bother with sterilizing the seawater. There are plenty of bacteria in marine muds that can withstand high pH, low pH and temperature extremes, but they usually would not be found in any quantity up in the water itself.

Mobjack, that is interesting. So I have a question on this topic. Would these bacteria that you mention be harmful to humans and if so, in what ways? If they survived the lye, could they or would they be likely to contribute to skin infections? If ingested would they or could they produce any internal problems? What would render them ineffective, if the answer are yes?

When I collected sea weeds, I did make sure there were no warnings for the waters from which I collected them, so hopefully if that is done when collecting the sea water, I would hope that would mean the water was safe as well. So in your professional opinion, would that be the case?
 
Thank you @Mobjack Bay! It's always nice to read the stuff you know about :)

I've used seawater several times. I'm almost running out. My cousin and my son collected about 3 liters from a very clean (apparently) beach they went to. The water was, in their words, unbelievably clear.

I only filtered it for sand or other bigger particles before using. I had a hunch that if not the heat from the lye, then the pH would probably get rid of anything that shouldn't be there. I'm hoping I was right
I'm watching out for those soaps and will report anything that seems out of the ordinary. So far, so good.

Having said that, I would worry about seawater closer to the city, and where I live. The Philippines is apparently the 3rd biggest ocean polluter, surprising considering we're a tiny country. Not surprising considering we're completely surrounded by, and cut through, with water, and as unfortunate as it is, logic dictates that most everything will probably find itself in the water.

As far as the behavior of saltwater goes, I notice no difference in using it compared to plain water, nor Zany's faux seawater, nor water with salt. Brine is an exception.
 
I haven’t used sea water for soap, but I have thoughts and questions.

1) Why not just make your own salt water with clean, fresh water and salt? Is there some unique quality to sea water?
2) If using sea water, why not process it in a pressure cooker to sterilize it and kill any bacteria/flora/fauna etc?
3) Anybody ever considered making a filter out of activated charcoal like the old middle school science experiment?
I just like the idea of real sea water if I can get it. Ages ago I made a soap with local sea water and sand (that coast has black sand) and they were a really cute little' gimmick'. I sold a lot of them at the market I go to, to tourists who liked the idea of taking home 'a little piece of NZ'.
fullsizeoutput_4da9.jpeg
 
As for the health risks of using seawater, we have lye going for us! With a quick search, I found a research paper that states that high pH (>10.5) “has previously been shown to exert a killing effect on bacteria.” https://aem.asm.org/content/aem/60/11/4009.full.pdf. Given that soap starts out with a pH in the 9-10 range, the lye water must be a higher pH (more concentrated NaOH), and hopefully it’s > 10.5. I am not a chemist, so I will try to confirm that or maybe someone here knows the typical pH for a lye:water mixture. I am not personally going to worry about bacteria living through the lye bath. On the other hand, some bacteria are very resistant to heat, especially if the exposure is for a relatively short period of time. That’s why they use heat at pressure in autoclaves and why it’s bad to eat undercooked chicken. I do worry about swimming at the beach if the beach is really crowded or in an urban area or associated with a Bay rather than the ocean. About 10 years ago, one of my son’s friends got a nasty infection when he stepped on a sharp object in a bay in a neighboring state. He had to be given massive doses of antibiotics and they also had to cut out a chunk of the bottom of his foot to clear it out.

This US EPA website gives information about the risks of swimming to human health, due to bacteria and other pathogens: https://www.epa.gov/beaches/learn-what-affects-human-health-beach. E. coli is a major culprit and there have also been reports of the bacteria that causes MRSA (antibiotic resistant staph) infections for some coastal waters and beach sand: https://www.livescience.com/3330-infectious-superbug-invades-beaches.html and http://www.beachapedia.org/Staph_Infections

You should definitely heed any posted warnings. We sometimes get those around here in the summer for shellfish growing areas that are not well flushed, close to homes with septic systems, etc. because clams and oysters will concentrate any bacteria that are in the water. If there are no posted warnings, I would not worry about collecting seaweed from areas that are away from cities and have good water exchange. I would rinse the seaweed well and then use it right away, dry it or freeze it to keep it fresh. Just like any vegetable! Given that we’re talking about soap/unfavorable pH and not something we’re going to eat, the chance of introducing bacteria via soap additives seems less likely to me than the chances of being exposed to pollutants like metals that the seaweeds might concentrate.

And one last thing for @earlene - as far as I am aware, glaciers form from a build up and compression of accumulated snow. Water melting from a glacier would be from pre-industrial times and for that reason would not have the pollutants that we have now. See this pitch for soap labeling ideas! https://www.alaskaglacier.com/. Makes me wish I lived near a glacier.
 
...I spent my career studying marine organisms and the sea around then and I can’t keep myself from jumping in on this thread
Thank You.gif

I'm SO glad you did, Mobjack! I've been waiting "forever" to meet someone knowledgeable like you to comment on the "Faux Sea Water" ingredients as shown in this thread:
https://www.soapmakingforum.com/threads/faux-sea-water.70733/
... 1) Why not just make your own salt water with clean, fresh water and salt? Is there some unique quality to sea water?
@DWinMadison Hopefully the link above and Mobjack's response will answer your question. As for me, located as I am in landlocked Colorado, I love the idea of being able to recreate/ approximate seawater with all its beneficial qualities to use in soap. ;)
As a sidebar - you can improve the taste of cheaper vodka by running it through a charcoal filter to remove some of the undesirable organic compounds. You wouldn’t want to do that with gin, which depends on organic compounds from juniper, lemon and florals for flavor and aroma.
It never ceases to amaze me -- the bits of trivia that come up on a soapmaking forum! Thanks again for jumping in on this thread.
 
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As for the health risks of using seawater, we have lye going for us! With a quick search, I found a research paper that states that high pH (>10.5) “has previously been shown to exert a killing effect on bacteria.” https://aem.asm.org/content/aem/60/11/4009.full.pdf. Given that soap starts out with a pH in the 9-10 range, the lye water must be a higher pH (more concentrated NaOH), and hopefully it’s > 10.5. I am not a chemist, so I will try to confirm that or maybe someone here knows the typical pH for a lye:water mixture. I am not personally going to worry about bacteria living through the lye bath. On the other hand, some bacteria are very resistant to heat, especially if the exposure is for a relatively short period of time. That’s why they use heat at pressure in autoclaves and why it’s bad to eat undercooked chicken. I do worry about swimming at the beach if the beach is really crowded or in an urban area or associated with a Bay rather than the ocean. About 10 years ago, one of my son’s friends got a nasty infection when he stepped on a sharp object in a bay in a neighboring state. He had to be given massive doses of antibiotics and they also had to cut out a chunk of the bottom of his foot to clear it out.

This US EPA website gives information about the risks of swimming to human health, due to bacteria and other pathogens: https://www.epa.gov/beaches/learn-what-affects-human-health-beach. E. coli is a major culprit and there have also been reports of the bacteria that causes MRSA (antibiotic resistant staph) infections for some coastal waters and beach sand: https://www.livescience.com/3330-infectious-superbug-invades-beaches.html and http://www.beachapedia.org/Staph_Infections

You should definitely heed any posted warnings. We sometimes get those around here in the summer for shellfish growing areas that are not well flushed, close to homes with septic systems, etc. because clams and oysters will concentrate any bacteria that are in the water. If there are no posted warnings, I would not worry about collecting seaweed from areas that are away from cities and have good water exchange. I would rinse the seaweed well and then use it right away, dry it or freeze it to keep it fresh. Just like any vegetable! Given that we’re talking about soap/unfavorable pH and not something we’re going to eat, the chance of introducing bacteria via soap additives seems less likely to me than the chances of being exposed to pollutants like metals that the seaweeds might concentrate.

And one last thing for @earlene - as far as I am aware, glaciers form from a build up and compression of accumulated snow. Water melting from a glacier would be from pre-industrial times and for that reason would not have the pollutants that we have now. See this pitch for soap labeling ideas! https://www.alaskaglacier.com/. Makes me wish I lived near a glacier.

I still have enough dried seaweed to probably last me the rest of my life and beyond. I keep it in mason jars and have a few different types. The last time I harvested any was about 10 years ago on the Pacific NorthWest Coast, but I don't live out there anymore, so I gathered loads and loads of it that last time and dried it at my brother's house, then and packed in my luggage for my return home. I have never had any ill effects from consuming seaweed I collected heeding safety warnings. But since I have so much of it and don't live near oceans anymore, I doubt I'll be gathering anymore for some time to come.
 
I've been waiting "forever" to meet someone knowledgeable like you to comment on the "Faux Sea Water" ingredients

Without doing any math, the first recipe strikes me as heavy on the bicarbonate. To mimic seawater you would be aiming for salt composition similar to what’s shown in the table here: https://en.m.wikipedia.org/wiki/Sea_salt#Composition
Note that there should be periods as decimal separators in those numbers, e.g. the concentration of chloride is 18.980 mg per liter, not 18,980 mg per liter (unless you’re outside the US and England where a comma is used instead of a period as the decimal separator)

And as a sidebar, at the ends of the wiki page it mentions that some sea salt is contaminated with microplastics. I had not heard that before. More on that here: https://www.nationalgeographic.com/...lastics-found-90-percent-table-salt-sea-salt/
 
I’m sure the TSA loved that :)


I actually expected some comment or other, and got nothing! No comment whatsoever. I wasn't called back to answer any questions. If they opened the luggage to take a closer look, I don't recall noticing (they usually tag it if so.) I actually don't even remember if it was checked luggage or carry-on, but I think it was checked luggage as the extra cost of checked luggage wasn't a thing yet.
 
A I do worry about swimming at the beach if the beach is really crowded or in an urban area or associated with a Bay rather than the ocean. About 10 years ago, one of my son’s friends got a nasty infection when he stepped on a sharp object in a bay in a neighboring state. He had to be given massive doses of antibiotics and they also had to cut out a chunk of the bottom of his foot to clear it out.
About 15 years ago we were on a cruise that had to stop at Fanning Island near the equator. Anyhoo this is an Atoll with a large lagoon. I told my girls to not go in that water since there was very little water exchange and the sanitation on the island was very poor. My so called sister let her kids go in and a similar thing happened with one of her daughter's. Bad infection and was sick the remainder of the trip. Justice does happen...she is the one that caused my daughter's epilepsy after knocking her over a table in mad fit from pills and alcohol. My kids were sure glad I reminded them of water exchange. :D

I do know this was a bit off topic, I will add this to keep on topic. Even though I live 20 miles from the ocean I do not collect sea water, it is so much simpler to make my own.
 
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