Copper Silver Organic Water Treatment

[Swimtrim]

I thought I would talk about Water Purification, Water Treatments, etc.

I have been a dealer, manufacturer, distributor in the Pool and Spa Industry for almost 20 years ... Many people talk about and ask what is a sanitizer? In order for any product to be listed as a sanitizer/purifier it must have EPA approval. Only 3 products have that;

1. Chlorine

2. Bromine

3. Bianguanides

All others are not EPA approved to use the claim sanitizes, purifies, etc.

I know this having been involved with development of a new mineral product. I along with 2 others have a patented water treatment product that utilizes, copper, silver and organics. We decided to patent our product when we did testing at an EPA approved lab. We obtained and had tests showing a log reductions on E-coli of 6 within 30 seconds.

Which means we had a 99.9999% kill rate within 30 seconds. A 99.99% kill rate is the log reduction that is needed to obtain a water purifier, sanitizer rating with the EPA ... At that point in time we decided to spend the $30,000 + to patent our product and go after the coveted EPA approval as a sanitizer/purifier. We would be the first and only mineral based product in the world with that rating, It was not to be ... We were not aware of the politics involved nor were we aware of the EPA's lack of giving answers to question or helping one understand the process thats needed in order to obtain approval as a purifier. We were repeatedly told, look at our website! ... I did and so did many others who could not figure out exactly what it was we needed, so we called them again and again we were told, look at our website ... can anyone look at their website and explain to me what it is I am looking for? http://www.epa.gov/

We wasted a lot of time and money and got no where.

Article on us at Pool & Spa News featured article, Making it to Market. http://www.poolspanews.com/2001/111/111market.html

Costs got prohibitive, dealers didn't want to carry our product due to how little the consumer had to pay to treat their hot tub with our 3 in 1 product. We were told by them, no matter how well your product works, why would we want to carry a product that does so many things, we lose money selling a product like yours We can sell and the consumer needs multiple products to do what your one product does alone.

It makes sense does it not? Dealers are established to take consumer dollars! The more the better and our product eliminates the need for several additional products all dealers sell in the retail stores.

We engineered our product to work without the need of calcium inhibitors, metal inhibitors and stain scale inhibition ... we did this by engineering our product with complexants that treated those problems and incorporating them into our product. It took years of research and development to get our product to work properly with high kinetic kill rates.

In essence each time you add our product it does 4 things eliminating the need for 3 additional products that are needed when using other mineral products. They all work well and are good alternatives to harsh chemicals.

If you look at copper sulfate based products they tell you to purchase other products that are needed to make their product work.

The same 3 types of products we have patented and engineered into ours which are, calcium inhibitor, metal inhibitor and scale inhibitor. We spent 8 years developing, testing and patenting our product. It has cutting edge technology which was developed by our head of research, Dr. Terry Ring

http://www.che.utah.edu/~ring/

Our product is being used by Humanitarian groups to treat contaminated water in 3rd world countries. We have a former retired environmental scientist who uses the product now, he was head of epidemiology as well as being in charge of water testing in Northern Utah at commercial water parks, hotels, motels, etc.

I met him a few years ago when I presented our product at the Health Dept. We were introducing our product at the time and he was at the meeting along with about 10 others. He later told me after meeting him again that everyone thought we were just your typical sales people trying to sell a miracle product that could not do what we claimed it did.

We had lab testing results and letters of recommendation with us at the meeting. No one told us at the meeting that we were being categorized as used car salesman ...

After he told me that, I offered to give him the product to try, I told him the proof is in the pudding ... that was 6 months ago. His response to me after having used it for 5 months was one of disbelief, he said, had he not tried it he would have never believed what we had stated at the meeting could possibly be true.

A month later, I supplied him with enough product for 17 doctors and scientists to use in Peru to treat their drinking water and to treat and test the contaminated source waters the villagers drink every day of their lives. They are in Peru as I write this.

My reason for writing this is not to sell product but to let people know some things do work and the cost, time and politics of the EPA can sometimes be a deterrent for small start-up companies especially those who have small budgets to get their products to market.

We know through extensive testing and use that our product does what it was engineered to do. Hundreds of thousands of dollars in time and money have been invested to produce a safe, healthy product, its been tested and used in hot tubs for several years without one incident of bacterial infection.

Lack of funding and knowledge of EPA protocols can and do hinder or stop great products from ever entering the market. I know this first hand, its frustrating and changes need to be made within our government agencies. When great products are developed, when they are safe and have the potential to add protection and safety to our precious waters .. I do believe the government shouldn't make it so difficult to get through the bureaucracy they have created ... I understand the need to introduce safe products that do what they claim they do but why is it so difficult and expensive to go through the hoops they make you jump through?

Can someone explain a simple, affordable way to deal with the EPA? ... any help would be appreciated!

[chem geek]

First of all, there are plenty of metal ion products that have been approved with lower amounts of chlorine (or bromine) and many of these have gone through NSF Standard 50 approval and are listed in this link. The EPA standard that is used for products that want to make disinfection claims for pools and spas is called DIS/TSS-12. The testing process requirements are described in more details in this link. Note that registering a pesticide with the EPA is only part of what needs to be done -- it also needs a specific use and the associated labeling and instructions are regulated by FIFRA rules. It is more difficult to have a new chemical registered with the EPA as a pesticide, but since you are already using metal ions and since those are already registered pesticides for algae (at least for copper), you can just pass the DIS/TSS-12 standard with instructions for use that include your "organics" if those are the fast-acting disinfectants (copper and silver are not fast enough by themselves).

You are wrong when you say that only chlorine, bromine, Baquacil/biguanide/PHMB have been approved by the EPA. Nature2 has been approved for use in spas without chlorine present during a soak. It uses silver (and zinc) ions in conjunction with specified levels of potassium monopersulfate (MPS aka non-chlorine shock). The instructions say to use Dichlor (i.e. chlorine) initially for superchlorination and then subsequently "as needed" but that is just to handle cloudiness since MPS may not oxidize everything that it needs to -- the primary disinfection during soaking is the combination of silver ions with MPS at hot spa temperatures (100-104ºF). Note that this is NOT approved for pools. The higher temperatures are needed to make the MPS much more reactive and the silver is needed in conjunction to achieve the necessary 6-log reductions against BOTH E.coli AND S.faecalis that need to be done using AOAC methods. Note that Nature2 is fairly simple and does not need the metal chelating or calcium reducing products you mention though I'm not sure how they limit the amount of silver (and zinc) ions that they introduce into the water to prevent staining, but spas aren't usually made of plaster so staining risks are lower to begin with. The MPS that is used is acidic so can keep the pH in check.

The bigger difficulty you might have is that the "organics" you are using as the primary fast-acting pesticide is going to need tests not only for efficacy (with the use of metal ions in your case), but also tests for safety. Nature2 was leveraging off of the already existing registration of copper and silver as well as MPS so could use those existing safety studies and just have to combine these to prove efficacy. You have a much bigger hill to climb unless your organics already have safety studies. You can look it up in the PAN Pesticide Database. If it's already a registered pesticide, then it will be easier for you to get approval; otherwise, the safety (toxicity) studies can be expensive -- anywhere from $500,000 to $1.5 million (no, I'm not joking because animal studies are not cheap) which is why it's only large companies that get such initial registrations and also why some companies pool together resources to get such registrations so that they can reuse and share studies rather than each company having to go through this individually.

I believe your patent application is in this link at the USPTO, is that correct? The patent essentially refers to the use of copper ions (from copper sulfate pentahydrate) along with di-sodium ethylene di-amine tetra-acetic acid dihydrate (otherwise known as EDTA) in addition to a scale inhibitor (the patent mentions 1-hydroxyethylidene-1,1-diphosphoric acid aka HEDP) and a shocking agent (the patent mentions monopotassium phosphate or potassium monopersulfate or sodium monopersulfate or alkali monopersulfates or potassium hydrogen peroxymonosulfate sulfate) and optionally a buffering agent (the patent mentions monopotassium phosphate or sulfuric acid or hydrochloric acid or nitric acid or muratic acid or oxalic acid) and optionally also has silver (the patent mentions silver nitrate).

You should not have listed in claim 7 monopotassium phosphate as a shocking agent since it isn't -- it's only a pH buffering compound (i.e. a phosphate buffer) and does not have oxidizing capability.

In your patent you refer to the bacteria studies with E.coli, but you also need to use S.faecalis as well to pass EPA DIS/TSS-12. You also need extensive real-world field studies in addition to the more stringent lab studies.

The good news is that EDTA is already listed in the PAN Database and is a registered pesticide (chelating agent) with the EPA. HEDP is not a registered on its own and its registration with copper in some products is canceled, but it is a common metal sequestrant (chelating agent) so should have safety/toxicity studies readily available. Monopersulfate (MPS) is registered in several shock products. Technically, the sequestrant and MPS need not be registered as pesticides if there are no pesticide claims (i.e. killing pathogens).

Now for the reality of your tests. Example B with copper ions and MPS might pass EPA DIS/TSS-12 at hot spa temperatures (silver + MPS does pass as was done with Nature2), but you are claiming (in the patent) that it passes in pools at much lower temps. I've spoken with Dupont about MPS in the past and there is no way that it would kill fast enough at the lower temps even with metal ions present and is why Nature2 was not able to use their silver ion plus MPS in pools. Even for spas it's right on the edge which is why the MPS levels have to be fairly high. Example A doesn't have MPS so just has copper ions and EDTA. Though EDTA can inhibit algae growth and is used in some algaecides, it does not kill bacteria quickly and is similar to MPS in that regard. Copper ions, of course, kill algae and are probably the most effective algaecide available (other than an appropriate FC/CYA ratio) but have the risk of staining if the concentration or pH get too high.

Copper ions do not kill bacteria quickly, taking roughly 40 minutes for a 2-log reduction of E.coli; silver ions kill faster, but still relatively slowly taking roughly 10-20 minutes for a 2-log reduction of E.coli. Contrast this with 1 ppm FC with no CYA taking around 5 seconds for a 2-log kill (around 15 seconds for 6-log). Metal ions are also rather ineffective against viruses. For example, this paper shows that copper ions do a 90% inactivation of Herpes Simplex Virus in 30 minutes at 100-200 ppm, but that is far, far higher in concentration than found in pools and spas where the copper is usually < 0.3 ppm in order to prevent staining. This paper shows that silver ions have virtually no effect on vacciniavirus, adenovirus, VSV, poliovirus, HVJ, but that with herpes simplex virus there is a 5-log kill in 60 minutes (roughly a 90% kill in about 5 minutes), but at over 3200 ppb compared to the usual limit of 20 ppb to prevent silver staining.

So you are probably getting some scoffs and disbelief because you don't have anything in your product that has been demonstrated to kill bacteria quickly (other than silver ions with MPS, but only at the hot temps of a spa). Also, you need to test S.faecalis and not just E.coli. The patent refers to 3-log reductions, not 6-log so that's also a problem, though even 3-log reductions seem unlikely with most of your formulations.

Now realistically, EPA DIS/TSS-12 is a ridiculously strict standard for the lab tests. In fact, the stabilized chlorine products (e.g. Trichlor and Dichlor) would never pass the lab tests if there were CYA already in the water as there is in pools using such products. The standard came out in 1979 not so many years after the 1974 O'Brien paper definitively determined the chlorine/CYA relationship, even though CYA's effects on kill times came out in studies in 1965, 1966, 1967, 1969, 1983, 1988 and 2009. The amount of active chlorine (hypochlorous acid) when CYA is present at a pH near 7.5 is very roughly equivalent to the FC/CYA ratio. 3 ppm FC with 30 ppm CYA has the same hypochlorous acid concentration as 0.085 ppm FC with no CYA so a factor of 35 lower. With the chlorine standard test there is no more than a factor of 2 leeway so there is no way that any real pool using CYA would pass the lab test. The field test requirements are far more lenient. The good news is that most pathogens are killed very quickly, but even for reasonable kill times to prevent person-to-person transmission they should be more like achieving 2-log (99%) kill in under 1 minute so basically a standard that is around 6 times looser and this would be for commercial/public pools thereby allowing 4 ppm FC with 20 ppm CYA (or 6 ppm FC with 30 ppm CYA) which is roughly equivalent to 0.2 ppm FC with no CYA. For residential pools, an even looser standard would be reasonable since person-to-person transmission is not as big a deal (you don't infect hundreds of people in essentially a large communal bath) and uncontrolled bacterial growth including biofilm formation is more of an issue. For pools a standard of an FC that is 5% of the CYA level which is equivalent of 0.04 ppm FC with no CYA would be enough to prevent algae growth using chlorine alone in SWG pools or an FC that is 7.5% of the CYA level which is equivalent 0.06 ppm FC with no CYA for manually dosed pools. Spas probably still need a higher standard perhaps near 4 ppm FC with 30 ppm CYA which is equivalent to 0.12 ppm FC with no CYA. And then there's the ridiculous 4 ppm FC maximum from the EPA that is based on drinking water standards that limit FIFRA labeling of pool products to no more than 4 ppm FC and spa products to 5 ppm FC (though many state regs ignore this and allow up to 10 ppm FC, especially for outdoor pools that usually have CYA in them). No one drinks quarts of pool water every day and the absorption of much chlorine through the skin is unlikely since 95% or more of it is bound to CYA as chlorinated isocyanurates and CYA has minimal skin absorption (see this paper).

What is unclear is whether even with such looser more rational lab standards your formulations would kill quickly enough in pools. I have no doubt that the silver ion plus MPS will be sufficient for spas and even copper plus MPS would probably work with looser standards, but it is unclear as to whether it would still work for pools as cool as 78ºF.

Take a look at the table in this post that I wrote when there were quite a few hot tub rash/itch/lung incidents reported on this forum. Note how many there are due to low sanitizer levels including a few using alternative no-chlorine sanitizer systems. There were also several using Dichlor-only where it appears that problems mostly occurred after the first or second month. This may have been due to the buildup of CYA that reduces chlorine's effectiveness. Out of that I suggested the Dichlor-then-bleach method where Dichlor is used initially for around a week or so to build up 30 ppm CYA and then bleach is used. To manage pH, this requires much lower TA and works best with 50 ppm Borates as well. The maintenance and cost of this system is very low. Most people add the chlorine after their soak such that they have a small residual (1-2 ppm FC) at the start of their next soak. This minimizes chlorine effects including disinfection by-products during the soak but it technically means the Free Chlorine (FC) gets to zero during some part of the soak (as monochloramine is quickly formed from ammonia in sweat and urine) so person-to-person transmission is still possible though uncontrolled bacterial growth is not (bacteria still take time to double in population). Urea is the largest component of sweat and urine and takes longer to oxidize, but is apparently very temperature dependent so gets handled within 24 hours in most cases. Most people using Dichlor-then-bleach can go around twice as long before changing the water compared to Dichlor-only that tends to get dull water earlier (due to slower oxidation rates from the rising CYA levels). Some people combine the Dichlor-then-bleach method with Nature2 where the metal ions provide continuous (though slower) disinfection even if the chlorine level gets to zero. Another popular method is the one I mentioned earlier of Nature2 with MPS. Though there have been no rash/itch/lung reports with these methods, it's way too early to tell since the sample size is rather small, especially with Dichlor-then-bleach.

As for pools, there are tens of thousands of people on this and other pool forums including The PoolForum and Trouble Free Pool who manage their own pools simply and inexpensively using mostly chlorinating liquid or bleach alone and sometimes a small amount of acid (some have saltwater chlorine generators). No clarifiers, flocculants, enzymes, algaecides, phosphate removers, or regular shocking. The key is understanding the chlorine/CYA relationship and maintaining an appropriate FC/CYA ratio to prevent algae growth, regardless of algal nutrients (e.g. phosphates, nitrates). My 16,000 gallon pool (shown here and here) is used by my wife as a therapy pool at around 88ºF every day for 1-2 hours plus longer on weekends when I also use the pool and has a mostly opaque electric safety cover so the daily chlorine usage is around 1 ppm FC per day. I use 12.5% chlorinating liquid from my pool store at $3 per gallon added around twice a week and the pool store reuses the bottles which is better than recycling. I add a small amount of acid every month or two. This all costs me around $15 per month in chemicals. It doesn't get much simpler or cheaper than that while still maintaining outstanding water quality including ample disinfection.

If you want to learn more about pool and spa water chemistry, a good place to start would be this post I wrote for improving the CPO course. It contains many links to scientific studies that will give you more info on the chlorine/CYA relationship and other aspects of pool/spa water chemistry. Also note the section on using CYA for indoor pools and spas to reduce volatile and irritating nitrogen trichloride.

Richard

[Swimtrim]

First of all, there are plenty of metal ion products that have been approved with lower amounts of chlorine (or bromine) and many of these have gone through NSF Standard 50 approval and are listed in this link. The EPA standard that is used for products that want to make disinfection claims for pools and spas is called DIS/TSS-12. The testing process requirements are described in more details in this link. Note that registering a pesticide with the EPA is only part of what needs to be done -- it also needs a specific use and the associated labeling and instructions are regulated by FIFRA rules. It is more difficult to have a new chemical registered with the EPA as a pesticide, but since you are already using metal ions and since those are already registered pesticides for algae (at least for copper), you can just pass the DIS/TSS-12 standard with instructions for use that include your "organics" if those are the fast-acting disinfectants (copper and silver are not fast enough by themselves).

You are wrong when you say that only chlorine, bromine, Baquacil/biguanide/PHMB have been approved by the EPA. Nature2 has been approved for use in spas without chlorine present during a soak. It uses silver (and zinc) ions in conjunction with specified levels of potassium monopersulfate (MPS aka non-chlorine shock). The instructions say to use Dichlor (i.e. chlorine) initially for superchlorination and then subsequently "as needed" but that is just to handle cloudiness since MPS may not oxidize everything that it needs to -- the primary disinfection during soaking is the combination of silver ions with MPS at hot spa temperatures (100-104ºF). Note that this is NOT approved for pools. The higher temperatures are needed to make the MPS much more reactive and the silver is needed in conjunction to achieve the necessary 6-log reductions against BOTH E.coli AND S.faecalis that need to be done using AOAC methods. Note that Nature2 is fairly simple and does not need the metal chelating or calcium reducing products you mention though I'm not sure how they limit the amount of silver (and zinc) ions that they introduce into the water to prevent staining, but spas aren't usually made of plaster so staining risks are lower to begin with. The MPS that is used is acidic so can keep the pH in check.

The bigger difficulty you might have is that the "organics" you are using as the primary fast-acting pesticide is going to need tests not only for efficacy (with the use of metal ions in your case), but also tests for safety. Nature2 was leveraging off of the already existing registration of copper and silver as well as MPS so could use those existing safety studies and just have to combine these to prove efficacy. You have a much bigger hill to climb unless your organics already have safety studies. You can look it up in the PAN Pesticide Database? If it's already a registered pesticide, then it will be easier for you to get approval; otherwise, the safety (toxicity) studies can be expensive -- anywhere from $500,000 to $1.5 million (no, I'm not joking because animal studies are not cheap) which is why it's only large companies that get such initial registrations and also why some companies pool together resources to get such registrations so that they can reuse and share studies rather than each company having to go through this individually.

I believe your patent application is in this link at the USPTO, is that correct? The patent essentially refers to the use of copper ions (from copper sulfate pentahydrate) along with di-sodium ethylene di-amine tetra-acetic acid dihydrate (otherwise known as EDTA) in addition to a scale inhibitor (the patent mentions 1-hydroxyethylidene-1,1-diphosphoric acid aka HEDP) and a shocking agent (the patent mentions monopotassium phosphate or potassium monopersulfate or sodium monopersulfate or alkali monopersulfates or potassium hydrogen peroxymonosulfate sulfate) and optionally a buffering agent (the patent mentions monopotassium phosphate or sulfuric acid or hydrochloric acid or nitric acid or muratic acid or oxalic acid) and optionally also has silver (the patent mentions silver nitrate).

You should not have listed in claim 7 monopotassium phosphate as a shocking agent since it isn't -- it's only a pH buffering compound (i.e. a phosphate buffer) and does not have oxidizing capability.

In your patent you refer to the bacteria studies with E.coli, but you also need to use S.faecalis as well to pass EPA DIS/TSS-12.

The good news is that EDTA is already listed in the PAN Database and is a registered pesticide (chelating agent) with the EPA. HEDP is not a registered on its own and its registration with copper in some products is canceled, but it is a common metal sequestrant (chelating agent) so should have safety/toxicity studies readily available. monopersulfate (MPS) is registered in several shock products. Technically, the sequestrant and MPS need not be registered as pesticides if there are no pesticide claims (i.e. killing pathogens).

Now for the reality of your tests. Example B with copper ions and MPS can pass EPA DIS/TSS-12 at hot spa temperatures, but you are claiming (in the patent) that it passes in pools at much lower temps. I've spoken with Dupont about MPS in the past and there is no way that it would kill fast enough at the lower temps even with metal ions present and is why Nature2 was not able to use their silver ion plus MPS in pools. Even for spas it's right on the edge which is why the MPS levels have to be fairly high. Example A doesn't have MPS so just has copper ions and EDTA. Though EDTA can inhibit algae growth and is used in some algaecides, it does not kill bacteria quickly and is similar to MPS in that regard. Copper ions, of course, kill algae and are probably the most effective algaecide available (other than an appropriate FC/CYA ratio) but have the risk of staining if the concentration or pH get too high.

So you are probably getting some scoffs and disbelief because you don't have anything in your product that has been demonstrated to kill bacteria quickly (other than silver ions with MPS, but only at the hot temps of a spa). Also, you need to test S.faecalis and not just E.coli. The patent refers to 3-log reductions, not 6-log so that's also a problem, though even 3-log reductions seem unlikely with most of your formulations.

Now realistically, EPA DIS/TSS-12 is a ridiculously strict standard for the lab tests because the stabilized chlorine products (e.g. Trichlor and Dichlor) would never pass the lab tests if there were CYA already in the water as there is in pools using such products. The standard came out in 1979 not so many years after the 1974 O'Brien paper definitively determined the chlorine/CYA relationship, even though CYA's effects on kill times came out in studies in 1965, 1966, 1967, 1969, 1983, 1988 and 2009. The amount of active chlorine (hypochlorous acid) when CYA is present at a pH near 7.5 is very roughly equivalent to the FC/CYA ratio. 3 ppm FC with 30 ppm CYA has the same hypochlorous acid concentration as 0.085 ppm FC with no CYA so a factor of 35 lower. With the chlorine standard test there is no more than a factor of 2 leeway so there is no way that any real pool using CYA would pass the lab test. The field test requirements are far more lenient. The good news is that most pathogens are killed very quickly, but even for reasonable kill times to prevent person-to-person transmission they should be more like achieving 2-log (99%) kill in under 1 minute so basically a standard that is around 6 times looser and this would be for commercial/public pools thereby allowing 4 ppm FC with 20 ppm CYA which is roughly equivalent to 0.2 ppm FC with no CYA. For residential pools, an even looser standard would be reasonable since person-to-person transmission is not as big a deal (you don't infect hundreds of people in essentially a large communal bath) and uncontrolled bacterial growth including biofilm formation is more of an issue. For pools a standard of an FC that is 5% of the CYA level which is equivalent of 0.04 ppm FC with no CYA would be enough to prevent algae growth using chlorine alone in SWG pools or an FC that is 7.5% of the CYA level which is equivalent 0.06 ppm FC with no CYA for manually dosed pools. Spas probably still need a higher standard perhaps near 4 ppm FC with 30 ppm CYA which is equivalent to 0.12 ppm FC with no CYA.

What is unclear is whether even with such looser more rational lab standards your formulations would kill quickly enough in pools. I have no doubt that the silver ion plus MPS will be sufficient for spas and even copper plus MPS would work with looser standards, but it is unclear as to whether it would still work for pools as cool as 78ºF.

Take a look at the table in this post that I wrote when there were quite a few hot tub rash/itch/lung incidents reported on this forum. Note how many there are due to low sanitizer levels including a few using alternative no-chlorine sanitizer systems. There were also several using Dichlor-only where it appears that problems mostly occurred after the first or second month. This may have been due to the buildup of CYA that reduces chlorine's effectiveness. Out of that I suggested the Dichlor-then-bleach method where Dichlor is used initially for around a week or so to build up 30 ppm CYA and then bleach is used. To manage pH, this requires much lower TA and works best with 50 ppm Borates as well. The maintenance and cost of this system is very low. Most people add the chlorine after their soak such that they have a small residual (1-2 ppm FC) during their soak. This minimizes chlorine effects including disinfection by-products during the soak but it technically means the chlorine gets to zero during some part of the soak so person-to-person transmission is still possible though uncontrolled bacterial growth is not (bacteria still take time to double in population). Some people combine this method with Nature2 where the metal ions provide continuous (though slower) disinfection even if the chlorine level gets to zero. Another popular method is the one I mentioned earlier of Nature2 with MPS. Though there have been no rash/itch/lung reports with these methods, it's way too earlier to tell since the sample size is rather small, especially with Dichlor-then-bleach.

If you want to learn more about pool and spa water chemistry, a good place to start would be this post I wrote for improving the CPO course. It contains many links to scientific studies that will give you more info on the chlorine/CYA relationship and other aspects of pool/spa water chemistry.

Richard

[Swimtrim]

Thanks for the response Richard and the information, most of which I am aware of.

If you noticed in our patents it states we can add other ingredients to what we have listed. We did not list all of our ingredients that were used in submitted samples. We submitted several samples to be tested with the results posted on the patent and I assure you we did have log reductions of 6 as stated. If your so interested in the results and the facts here is the link http://www.freepatentsonline.com/6824794.html

All of those samples were tested under EPA guidelines at an EPA approved lab ...

As to your claim that Nature 2 is a stand alone purifier with EPA registration is that only for hot tubs? I sold the Nature 2 cartridge at our store when it first came out on the market, it didn't have EPA approval then. Does it have EPA approval for commercial use in hot tubs and pools? Typically you need to be able to test for residual levels of the sanitizer in the water in order to do any commercial purification. Does Nature 2 now offer a test strip or reagent to show the amount of ions (ppm) in the water?

I've not been active in the Pool & Spa Industry for several years as I am pursuing the Humanitarian side of things at the moment so I don't have the answers to those questions.

I do appreciate the time you must have taken to respond to my posting, out of curiosity do you work for a company who sells products in the pool and spa market? I would love to talk to you sometime on the phone, you seem to be extremely knowledgeable and you are correct in your assessment of log reductions with typical copper sulfate products.

[chem geek]

I couldn't find the patent earlier because it is under the name "Smolkov" instead of "Smokoff" as in the patent application and the article you linked to, so thanks for the direct link. I do not work in this industry nor am I a chemist and am just a pool owner with a strong interest in pool and spa water chemistry (you can get a spreadsheet I wrote that calculates the hypochlorous acid concentration, among other things, in this link).

You wrote "We did not list all of our ingredients that were used in submitted samples." Although the patent refers to other acids, complexants, scale inhibitors and other non-chlorine shocks that may be used, unless you were to use a more powerful oxidizer or sanitizer, you would not be able to achieve 6-log reductions in bacteria in cooler water. Yes, you could have a "secret" ingredient similar to an organic molecule such as Baquacil/biguanide/PHMB that incorporates into bacterial cell walls disrupting ion transport (this also occurs to a lesser extent with Polyquat algaecide), but not explicitly mentioning such an ingredient in the patent means that it is not patented and is instead a trade secret which begs the question of why create a patent in the first place if the "key" ingredient isn't even in the patent? Also, listing tables of efficacy in the patent using "missing" ingredients not described in the patent is misleading and may invalidate the patent if challenged. That patent explicitly stated that "each of the formulations listed" were tested -- it didn't say that other secret ingredients were added. Heck, you could add potassium permanganate which is a very strong oxidizer, but wouldn't be something you'd want exposed to your body.

The formulations you used were diluted to 1.2 ppm copper in most cases and that is a level that will generally cause staining, especially to plaster (and probably fiberglass) surfaces unless the pH is kept very low closer to 7.0, but then the rates of metal corrosion are a bit higher at that lower pH and it is less pleasant to the eyes where tears have an average pH of 7.5 (see this paper). Also, the results in the tables don't make any sense at all. Even EcoSmarte and similar systems usually limit the copper ion concentrations to 0.7 ppm with the pH kept closer to 7.0. Perhaps you are measuring total metal ion concentrations, not the "free" amount that is unbound to the extensive EDTA and HEDP metal sequestrants, but the metal bound to such sequestrants is not active for sanitation. In Table 1, the 0.6 ppm chlorine standard tapped out at 3.2-log reduction with no further reduction over time which is very strange while Table 2 had a 6-log reduction using the same chlorine amount. Also, example B with high MPS concentrations had a low 0.2-log reduction (this is more typical of what would be seen with copper and MPS at low pool temps). Examples A and D were the same except that A had more EDTA and resulted in 2.4-log reduction instead of 6-log reduction with D. Basically, your results are all over the map. This is why repeated testing is normally done throwing out outliers. It may also be why the EPA is skeptical of the results. In Example D, you were showing 6-log reductions in 30 seconds using only copper sulfate (at 1.2 ppm) with EDTA, HEDP and a phosphate buffer so without disclosing your special ingredient (which would then need safety/toxicity data), how can you blame the EPA for questioning such data?

The Nature2 EPA registration as a non-chlorine sanitizer (what they call the "low chlorine" recipe since chlorine is used for superchlorination initially and "as needed") is for the specific combination of their Nature2 cartridge PLUS a moderately high MPS level and ONLY for spas (i.e. hot temperatures). This is all described in detail in their owner's manual and you can see their press release in 2007. The manual describes the use of test strips for determining the MPS level, but nothing for determining the silver ion concentration. My hunch is that the superchlorination oxidizes some of the cartridge material to release a mostly fixed starting amount of silver ion and that there is a small subsequent trickle of silver ion thereafter. Since it's silver and not copper ion, it's probably on the order of 20 ppb or so. I cannot tell whether Nature2 was approved for commercial spa use or whether it is restricted to residential spas. From the Nature2 website, it appears that it is only being sold/marketed to the residential spa market.

Richard

[Swimtrim]

Hello RIchard,

Again I thank you for your reply. You seem a bit hostile, I am not here to argue with you nor do I want to correct your erroneous pre-miss-conceptions regarding our tests and the results.

FYI ,,, I will say in defense of our product, we've done extensive testing. All of our tests were conducted with approval from local health departments at commercial facilities and we did testing on both hot tubs and swimming pools.

We did daily bacterial testing which are a small part of the requirements needed to have a product approved by the EPA as a stand alone commercial purifier.

We followed their guidelines (EPA) for bacterial testing which are needed for approval in any commercial application. Those guidelines are much more stringent than needed for a product for residential use only.

We used independent labs (EPA approved) to conduct all of the bacterial testing, those tests were conducted on a daily basis and we passed with flying colors, including state specific standards.

I won't go into any further detail with you, because of your skepticism regarding our testing and product. I didn't post to start an argument I posted to see if anyone had gone through the quagmire of the EPA and may be able to simplify things ...

One last thing in parting as I will no longer be posting here again.

As noted in our patents, our present invention is not limited to the examples we presented nor the formulations listed and I quote from the patent.

"The preferred embodiments of the present invention, it is to be understood that the invention is not to be limited by particular details set forth in the above description, as many apparent variations thereof are possible without departing from the spirit or scope of the present invention."

Perhaps you can give me your input regarding what the last paragraph implies? You seem an expert in many areas and I would welcome your opinion.

[chem geek]

Sorry if I seemed hostile. You were the one that wrote that you used additional ingredients not listed in the patent for the testing and on first glance, that seems misleading to me. Patents must be written in a way that those skilled in the art can recreate what you have done. The statement about variations (which is a generic statement put into most patents) refers to those that would be obvious to those skilled in the art. It would not include having any additional "secret" ingredient that was critical to achieve 6-log reductions in bacterial counts and that would not be an obvious ingredient. Any such ingredient would need to be disclosed to the EPA so that they ensure that it is safe.

I gave you feedback with regard to what would seem strange to someone looking from the outside, such as the EPA. I wasn't going to sugarcoat it and gave you honest feedback. I was most certainly put off by the implication of a secret ingredient not disclosed in a patent application, but with results that may have used such an undisclosed ingredient. I think most people would consider that to be dishonest. You have an option to not file a patent if you don't want your secret ingredient disclosed -- it would then be a trade secret. However, it would likely have to be disclosed to the EPA for safety and therefore most likely end up in an MSDS unless it was a proprietary ingredient that was deemed to have virtually no toxicity (which, by definition, wouldn't happen for an ingredient that killed bacteria since it would be a pesticide by definition).

As for EPA DIS/TSS-12, it is a standard used for FIFRA labeling in both residential and commercial/public pools. There isn't a separate labeling standard for residential pools. What you are talking about in terms of differing standards is for state and local regulations of use and in that case commercial/public pools are regulated and require an EPA-approved disinfectant per DIS/TSS-12 while residential pools have no such regulations at all with regard to chemical usage. One can soak in raw sewage as far as the government is concerned. The only regulations for chemicals affecting residential pools are the FIFRA labeling rules. Homeowners are not required by law to use EPA approved sanitizers in their pools which is why there is a fairly large proliferation of alternative sanitizers available including natural pools/spas with sphagnum moss, pools/spas with only metal ions, pools/spas with just enzymes, etc. In other words, you are free to sell your product as is so long as you make no sanitizer/disinfectant claims on the label, or you can claim that it is an algaecide due to the copper ions, but cannot claim it disinfects or kills bacteria, etc. without passing DIS/TSS-12 (disclosing all ingredients so that safety can be determined).

[chem geek]

I spoke to Swimtrim on the phone. Any extra ingredients are for formulation or enhancement, but not what was disclosed in the patent and presumably not what was given to the lab. So the lab results showed from Example D that by simply having copper ions (from copper sulfate pentahydrate at 1.2 ppm), a phosphate pH buffer, and two metal sequestrants (EDTA and HEDP), one achieved 6-log reductions of E.coli in 30 seconds. Either what was given to the lab had something else in it, or the lab didn't do the test carefully, or we have a new fast-acting disinfectant.

[waterbear]

I spoke to Swimtrim on the phone. Any extra ingredients are for formulation or enhancement, but not what was disclosed in the patent and presumably not what was given to the lab. So the lab results showed from Example D that by simply having copper ions (from copper sulfate pentahydrate at 1.2 ppm), a phosphate pH buffer, and two metal sequestrants (EDTA and HEDP), one achieved 6-log reductions of E.coli in 30 seconds. Either what was given to the lab had something else in it, or the lab didn't do the test carefully, or we have a new fast-acting disinfectant.

I vote for any but the last choice.

Also, 1.2 ppm copper is definitely high. Most ionizes and liquid copper based systems (and copper/silver systems also) maintain the copper from a low of aobut .6 ppm to 1 ppm and this range can and does stain!