Some Info On Metal Toxicity!
- Thread starter Graeme Edwards
- Start date
Saedcantas
Fishaholic
While Aluminium is not a "heavy" metal, it is one of the trace metals which has no beneficial or metabolic use in the bodies of organisms.
And is known to be a metalloestrogen (mimics and interrupts hormonal processes) and toxic in higher levels.
And is known to be a metalloestrogen (mimics and interrupts hormonal processes) and toxic in higher levels.
Honestly Bloozoo that's sidestepping the questions I'm asking (which would be fair enough, but you do seem to be replying directly to my posts).
TBH you clearly are advocating pumping more unnecessary chemicals or purifiers into our tanks, by encouraging the addition of Sodium Thiosulphate to supplies that do not need it.
To be frank, anyone who has no idea how to obtain water analysis information isn't going to be able to add much to this and their individual shortfalls aren't the topic here. I agree with you about the documentation the water firms supply though, it is daunting, and when you don't know the toxicity of the concentrations of the various components of the water it's difficult to know where to start.
Your point about "Water supplies also constantly change... ...how are you going to know what the latest additive is" is a red herring. If you don't know, do you think API or Hagen do? Especially given that there is more diversity across the country's supply than there is variation within an area's (although Thames probably does show a good range of variation). Do you think these firms monitor the water supplies and vary their products as a result? Not a chance, unless it were as a result of a wholesale revolution in water treatment procedures.
You cannot trust the manufacturers of dechlorinator to take care of the undesirable aspects of your supply, that much is becoming apparent. I've illustrated that by drawing attention to the fact that API Tap Water Conditioner doesn't treat anything other than Chlorine and Chloramine- which is completely unnecessary for a good proportion of the UK's fishkeepers and totally avoids any other chemicals, additives, or heavy metals that might be in your supply.
Even the much praised Stresscoat only deals with heavy metals in addition to Cl. However, we have yet to look at any information about how it does that, what the compounds formed are and the long term effects of them are (the metal isn't going anywhere at the end of the day), or what the result is of overdosing on that aspect of the solution.
@ MOODY/BIGNOSE- does your book give any information on how to chemically fix heavy metals in an aquatic setting (other than RO)? Or the toxicity of the resulting compounds?
The reply from Hagen is an interesting one, I wonder what the reply might have been from British American Tabacco had you e-mailed them 30 years ago about the effects of smoking. Can you trust their response? Absolutely not, based on the questions posed regarding their objectives when you consider their packet labelling. They may well have tested to 100 times the dose, but for how long? What cumulative effects have been studied? Why are these fish not fit for human consumption as a result of living in water treated by their products?
Are you really better safe than sorry dosing for the sake of it, or are you lulled into a false sense of security?
Do you not agree that there are far more questions than answers here?
What I'm personally seeking is the knowledge on how and why to tailor my own water treatment effectively without blindly following the masses.
I suspect that unless we have input from a chemist as to how to fix heavy metals directly, we have little choice in how to proceed, and that's the end of that! Pity really.
TBH you clearly are advocating pumping more unnecessary chemicals or purifiers into our tanks, by encouraging the addition of Sodium Thiosulphate to supplies that do not need it.
To be frank, anyone who has no idea how to obtain water analysis information isn't going to be able to add much to this and their individual shortfalls aren't the topic here. I agree with you about the documentation the water firms supply though, it is daunting, and when you don't know the toxicity of the concentrations of the various components of the water it's difficult to know where to start.
Your point about "Water supplies also constantly change... ...how are you going to know what the latest additive is" is a red herring. If you don't know, do you think API or Hagen do? Especially given that there is more diversity across the country's supply than there is variation within an area's (although Thames probably does show a good range of variation). Do you think these firms monitor the water supplies and vary their products as a result? Not a chance, unless it were as a result of a wholesale revolution in water treatment procedures.
You cannot trust the manufacturers of dechlorinator to take care of the undesirable aspects of your supply, that much is becoming apparent. I've illustrated that by drawing attention to the fact that API Tap Water Conditioner doesn't treat anything other than Chlorine and Chloramine- which is completely unnecessary for a good proportion of the UK's fishkeepers and totally avoids any other chemicals, additives, or heavy metals that might be in your supply.
Even the much praised Stresscoat only deals with heavy metals in addition to Cl. However, we have yet to look at any information about how it does that, what the compounds formed are and the long term effects of them are (the metal isn't going anywhere at the end of the day), or what the result is of overdosing on that aspect of the solution.
@ MOODY/BIGNOSE- does your book give any information on how to chemically fix heavy metals in an aquatic setting (other than RO)? Or the toxicity of the resulting compounds?
The reply from Hagen is an interesting one, I wonder what the reply might have been from British American Tabacco had you e-mailed them 30 years ago about the effects of smoking. Can you trust their response? Absolutely not, based on the questions posed regarding their objectives when you consider their packet labelling. They may well have tested to 100 times the dose, but for how long? What cumulative effects have been studied? Why are these fish not fit for human consumption as a result of living in water treated by their products?
Are you really better safe than sorry dosing for the sake of it, or are you lulled into a false sense of security?
Do you not agree that there are far more questions than answers here?
What I'm personally seeking is the knowledge on how and why to tailor my own water treatment effectively without blindly following the masses.
I suspect that unless we have input from a chemist as to how to fix heavy metals directly, we have little choice in how to proceed, and that's the end of that! Pity really.
Bloo
~ I learn something new ~ ~~~~ every day ~~~~
So do you have any idea what proportion of the UK's drinking water supplied to households are so pure it doesn't need dechlorinating ? Out of interest ? Or then does not have any additives / heavy metals that need removing or render harmless ? I feel far safer adding API Stress Coat (dechlorinator water conditioner etc). to my tank than leaving it in the hands of my local water supplier.
I can't answer all your questions - I'm not a scientists or household water quality expert.
But I can be quite cynical too
(and like you want answers to my questions).However, I have come to understand that the vast majority of us sit with water supplies that are harmful to our fish to use as is, neat and untreated.
E.D.T.A. (Ethylene Diamine Tetra Acidic Acid) is commonly used to chelate or bind heavy metals into 'safe' form i think its actually used as a treatment in heavy metal posioning in humans.
I use it in the lab to stop undesirable enzymatic reactions which have metals as co-factors, the EDTA takes them out of commision and stops the enzyme in its tracks.
Not sure i would advocate putting it in the tank though as it will pretty much remove all metals (even the benefical ones).
Plus found a reference in PUBMED suggesting that edta chelated copper when added to water caused an accumulation of copper in the gills of fish.
however also found the following on the national fish pharmeucticals website
Heavy Metals
Well water may contain ferrous bicarbonate, detected by a brown precipitate that forms when neutral or alkaline water is aerated. Besides being mildly irritating to the fish, ferrous bicarbonate stains equipment and causes water to become cloudy.
E.D.T.A. (Ethylene Diamine Tetra Acidic Acid) can be used to chelate out any heavy metals such as iron or copper from the water. To make a stock solution with EDTA, use 1 teaspoon and mix it with 4 ounces of distilled water. Shake well. Then use 2 drops of this stock solution per gallon of pond water. EDTA will lower your pH, so care should be used when adding it to the pond. We suggest taking a pail of water out of the pond, check the pH and then add 2 drops of EDTA per gallon of pail water. Mix the water well and then test the pH once again. The maximum amount per day that the pH may be dropped is 0.2, any more can pH shock the fish, make the fish stressed and cause a disease outbreak in the pond.
I use it in the lab to stop undesirable enzymatic reactions which have metals as co-factors, the EDTA takes them out of commision and stops the enzyme in its tracks.
Not sure i would advocate putting it in the tank though as it will pretty much remove all metals (even the benefical ones).
Plus found a reference in PUBMED suggesting that edta chelated copper when added to water caused an accumulation of copper in the gills of fish.
however also found the following on the national fish pharmeucticals website
Heavy Metals
Well water may contain ferrous bicarbonate, detected by a brown precipitate that forms when neutral or alkaline water is aerated. Besides being mildly irritating to the fish, ferrous bicarbonate stains equipment and causes water to become cloudy.
E.D.T.A. (Ethylene Diamine Tetra Acidic Acid) can be used to chelate out any heavy metals such as iron or copper from the water. To make a stock solution with EDTA, use 1 teaspoon and mix it with 4 ounces of distilled water. Shake well. Then use 2 drops of this stock solution per gallon of pond water. EDTA will lower your pH, so care should be used when adding it to the pond. We suggest taking a pail of water out of the pond, check the pH and then add 2 drops of EDTA per gallon of pail water. Mix the water well and then test the pH once again. The maximum amount per day that the pH may be dropped is 0.2, any more can pH shock the fish, make the fish stressed and cause a disease outbreak in the pond.
Currently I could give you that information for about 80% of the UK's water supplies. When that reaches 100% I shall be making a post on the subject. As a sneak preview I can tell you for example Thames' policy (bear in mind all UK water supplies contain Chlorine, so the need to dechlorinate is based on chloramine content):
Yes but the point is this: What additives? Dechlorinators do not claim to remove anything other than Chlorine, Chloramine, and in some cases to fix heavy metals. If there are other additives that are harmful to fish they ain't getting sorted by dechlorinators, nor are they being sorted with "water conditioners". So by elimination, for a good proportion of the population all you're effectively removing is heavy metals, if even that. I would like to see if there is another way to achieve this heavy metal removal that doesn't involve dosing extra, supurfluous chemicals.
Granted, and I'm certainly not suggesting that you're not doing the righ thing. According to current wisdom, we don't have a hell of a lot of choice other than to go RO. But current wisdom is agreed and the discussion is about moving forwards as far as I'm concerned.
I can't answer all your questions - I'm not a scientists or household water quality expert.
But I can be quite cynical too
Excellent, let's see what we can find out as a group. We have some awesome resources on this forum, some help would be much appreciated.
True. How many of us realise the shortfalls of dechlorinators generally though, and how many more think they are making their water safe but are actually pouring good money after bad?
This really is an area of which I have been blissfully ignorant, and perhaps it is my frustration at that, and the lack of solid information on this subject, that is making me feel so much like a dog with a bone now I see the issue exists.
andywg
Bored into leaving
It would appear that Saedcantas is correct and aluminium is not a hevy metal, as the cut off for "heavy" metals is those that have a Specific Gravity of 4.0 or greater.
http
/en.wikipedia.org/wiki/Heavy_metals
http
/en.wikipedia.org/wiki/Heavy_metals
Bloo
~ I learn something new ~ ~~~~ every day ~~~~
However it does also goes on to say (though in true scientific terms obviously not):
Graeme Edwards
Fishaholic
Im with you Jules H-T and others.
I cant help but notice that the water treatments say that they remove the heavy metals, how exactly?? do they attach them selfs to little scud missiles and leave your water when your not looking( i dont think so!)
I dont agree with pumping our water with all these water treatmets just to stablise our water.
I thinks if we are realy concerd about the water that we put into our tanks then i dont think adding our purchased chemicals to the water companys chemicals is the way to move forward.
If we are just concerd about metal toxicity then yes there are chemicals that NUTRALISE not remove the threat of heavy metals, if we are concerd about unwanted and potentialy harmfull chemicals that water conditioners do very little,then IMO its either RAIN WATER(proberly the most natural) or RO water!
As for what the books says about binding metals, It refurs to using plants that are fast growers and that are metal hungry plants to help remove some of the threat. It also mentions that heavy metals in hard water is somthing no to be worreid about( i cant quote im at work).
In summery Its either rain water or RO for real peice of mind IMO.
I cant help but notice that the water treatments say that they remove the heavy metals, how exactly?? do they attach them selfs to little scud missiles and leave your water when your not looking( i dont think so!)
I dont agree with pumping our water with all these water treatmets just to stablise our water.
I thinks if we are realy concerd about the water that we put into our tanks then i dont think adding our purchased chemicals to the water companys chemicals is the way to move forward.
If we are just concerd about metal toxicity then yes there are chemicals that NUTRALISE not remove the threat of heavy metals, if we are concerd about unwanted and potentialy harmfull chemicals that water conditioners do very little,then IMO its either RAIN WATER(proberly the most natural) or RO water!
As for what the books says about binding metals, It refurs to using plants that are fast growers and that are metal hungry plants to help remove some of the threat. It also mentions that heavy metals in hard water is somthing no to be worreid about( i cant quote im at work).
In summery Its either rain water or RO for real peice of mind IMO.
andywg
Bored into leaving
I debate that "medical" usage as being lighter.
I have never heard of heavy metal poisoning refer to aluminium. Lead: yes. Zinc: yes. Never aluminium.
And besides, that refers to a condition called "heavy metal poisoning" not to the heavy metals themselves. I would wager it is because an overdose of those lighter metals exhibits itself in a similar way on the body as an overdose of heavy metals.
Evidence of this exists in this health based article on heavy metal poisoning (aluminium is mentioned at the bottom):
http/www.lef.org/protocols/prtcl-156.shtml#toxic
I have never heard of heavy metal poisoning refer to aluminium. Lead: yes. Zinc: yes. Never aluminium.
And besides, that refers to a condition called "heavy metal poisoning" not to the heavy metals themselves. I would wager it is because an overdose of those lighter metals exhibits itself in a similar way on the body as an overdose of heavy metals.
Evidence of this exists in this health based article on heavy metal poisoning (aluminium is mentioned at the bottom):
http
/www.lef.org/protocols/prtcl-156.shtml#toxic
Saedcantas
Fishaholic
Where to begin!!!
On the subject of how exactly do dechlorinators supposedly "remove" heavy metals, Delboy has already said much of what I was about to say
The important factor that Delboy was wondering about though, you certainly wouldnt want to intentionally add a Chelating agent such as EDTA to your fishtank because it is a very strong chelating agent with a high redox potential.
Chelating agents such as Sodium Thiosulphate (using a "Sulphate reduction" reaction) however, are only moderate chelating agents at best and therefore doesnt pose the same problem of voiding your water of all metals including those that are beneficial to metabolic processes
For those of you wondering what on earth I am spouting on about!
A chelating agent reacts with metallic compounds or elemental metals in such a way that the metal component is then effectively "removed" from availability and cannot be absorbed or used while in that state. In the case of Sodium Thiosulphate, Sulphate ions are produced as a result
Essentially (unless I'm very much mistaken! I'm a Geologist/Biologist not a Chemist ) When you use a dechlorinator that contains Sodium Thiosuphate you are left with metallic salts (the heavy metals are bound here) and Sulphate ions, which providing you do water changes ever, will be removed.
Also, since freshwater fish (which is what we are concerned with in this section of the forum at least) are Hyperosmotic, they tend to take in water and lose ions involuntarily, they only gain ions via selective uptake (which does not include sulphate ions) or via their food (which shouldnt therefore contain the sulphate ion by-product of dechlorination).
So, in theory, our fish shouldnt be bothered by the by-products of dechlorination using Sodium Thiosulphate.
Also, it might interest people to research Metallothionines, which are Cysteine (amino acid) rich proteins found in a vast array of all organisms which deal directly with chelating metals within organisms in order to sequester them for excretion. These proteins function essentially in a similar fashion to our Sodium Thiosulphate by binding potentially harmful metals and they too produce ionic by-products.
The long and short of all that I just waffled out (for those of you who actually made it this far!!!) is that I personally dont think we are causing problems with the dechlorinators that we use and I will continue to use mine.
That is until someone who knows more about it than me and is actually a Chemist shows up and tells me I was all wrong
On the subject of how exactly do dechlorinators supposedly "remove" heavy metals, Delboy has already said much of what I was about to say
The important factor that Delboy was wondering about though, you certainly wouldnt want to intentionally add a Chelating agent such as EDTA to your fishtank because it is a very strong chelating agent with a high redox potential.
Chelating agents such as Sodium Thiosulphate (using a "Sulphate reduction" reaction) however, are only moderate chelating agents at best and therefore doesnt pose the same problem of voiding your water of all metals including those that are beneficial to metabolic processes
For those of you wondering what on earth I am spouting on about!
A chelating agent reacts with metallic compounds or elemental metals in such a way that the metal component is then effectively "removed" from availability and cannot be absorbed or used while in that state. In the case of Sodium Thiosulphate, Sulphate ions are produced as a result
Essentially (unless I'm very much mistaken! I'm a Geologist/Biologist not a Chemist
) When you use a dechlorinator that contains Sodium Thiosuphate you are left with metallic salts (the heavy metals are bound here) and Sulphate ions, which providing you do water changes ever, will be removed.Also, since freshwater fish (which is what we are concerned with in this section of the forum at least) are Hyperosmotic, they tend to take in water and lose ions involuntarily, they only gain ions via selective uptake (which does not include sulphate ions) or via their food (which shouldnt therefore contain the sulphate ion by-product of dechlorination).
So, in theory, our fish shouldnt be bothered by the by-products of dechlorination using Sodium Thiosulphate.
Also, it might interest people to research Metallothionines, which are Cysteine (amino acid) rich proteins found in a vast array of all organisms which deal directly with chelating metals within organisms in order to sequester them for excretion. These proteins function essentially in a similar fashion to our Sodium Thiosulphate by binding potentially harmful metals and they too produce ionic by-products.
The long and short of all that I just waffled out (for those of you who actually made it this far!!!) is that I personally dont think we are causing problems with the dechlorinators that we use and I will continue to use mine.
That is until someone who knows more about it than me and is actually a Chemist shows up and tells me I was all wrong
Bloo
~ I learn something new ~ ~~~~ every day ~~~~
Wow Saedcantas - I had to read that a few times 
but I *think* I get it. Very interesting 
but I *think* I get it. Very interesting Graeme Edwards
Fishaholic
heavy man!Cheers Delboy (sorry mate I totally missed your post) and Saedcantas, just the sort of info I was looking for.
OMG my A levels are coming flooding back. Sodium Thiosulphate is something I used to use in titrations with iodine and is an RA! Wow, I KNEW it was familiar, can't believe I never made the connection lol
So the basic dechlorination process is:
Na2S2O3 + 4Cl2 + 5H2O = 2NaHS04 + 8HCl
Showing that as a product of the dechlorination process you're getting Hydrochloric acid and Sodium Sulphate produced, right? So how come it doesn't mess with your pH?
Sorry if this is veering off topic a bit, I'm trying to develop a picture of the whole process (chloramines next once I'm clear on this, then the metals)!
---------------------------------------------------------------------------------
Back on topic a little more, it's looking like the strength of the RA dictates how much/many metals it fixes. Is it related to atomic mass or ionic charge does anyone know?
I notice the warning given with EDTA that it reduces pH. Is that because of rections similar to the above also producing hydrochloric acid?
OMG my A levels are coming flooding back. Sodium Thiosulphate is something I used to use in titrations with iodine and is an RA! Wow, I KNEW it was familiar, can't believe I never made the connection lol
So the basic dechlorination process is:
Na2S2O3 + 4Cl2 + 5H2O = 2NaHS04 + 8HCl
Showing that as a product of the dechlorination process you're getting Hydrochloric acid and Sodium Sulphate produced, right? So how come it doesn't mess with your pH?
Sorry if this is veering off topic a bit, I'm trying to develop a picture of the whole process (chloramines next once I'm clear on this, then the metals)!
---------------------------------------------------------------------------------
Back on topic a little more, it's looking like the strength of the RA dictates how much/many metals it fixes. Is it related to atomic mass or ionic charge does anyone know?
I notice the warning given with EDTA that it reduces pH. Is that because of rections similar to the above also producing hydrochloric acid?
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