6 ms·

I will just leave it here in case someone will want to employ copper pots: https://www.ncbi.nlm.nih.gov/pubmed/10383875 https://www.ncbi.nlm.nih.gov/pubmed/1038

• allannienhuis 9y ago
  Interesting. Two studies with pretty much conflicting conclusions about safety of copper for potable water. I imagine that there is a level (range) of exposure that is in the sweet spot between 'kills harmful microbes' and 'kills/harms humans who drink the water'.
  • maxxxxx 9y ago
    One study is abut storing water in copper pots and the other is about copper in drinking water. Does storing water in pots automatically mean that the copper goes into the water and if yes, how high is the concentration?
    • cmrx64 9y ago
      TFA looked at the copper concentration in the water after storage and it was below WHO guidelines for safe copper levels. Whether the WHO guidelines are sufficient or not is another question.
      • kleiba 9y ago
        The WHO guideline for copper is 2mg/l which is the same as in the German guidelines "Trinkwasserverordnung". The article linked by batter says right in the abstract: We found that the disease can even be caused by copper concentrations below the allowed concentration given by the German Guidelines for Drinking Water (Trinkwasserverordnung).
      • deleted 9y ago
        [deleted]
    • thatcat 9y ago
      >Does storing water in pots mean that Cu goes into water It's not automatic, but depends on pH. Acidic conditions will be favorable to metals leaching into water. The paper cites an initial pH of 7.84, and final pH of 7.94 - so the pH increased slightly as a result of the copper entering the solution. This pH change correlated with 177 ppb Cu concentration in these pots after 16 hours. If initial pH was lower this concentration would see a logarithmic increase in relation the lower initial pH over the same time interval. "Since distilled water is slightly acidic (pH 6.7±0.05) which might enhance copper leaching, we have demonstrated the effect of copper pot in regular drinking-water"
      • std_throwaway 9y ago
        A quick google says: Drinking water in the US of A must have at least a pH of 6.5. They should have tested with that. I assume, the copper concentration would increase over 10-fold in that case versus the tested case.
    • LgWoodenBadger 9y ago
      How is storing it in copper pots significantly different than "storing" it in the copper pipes prevalent in a majority of houses in the USA?
      • jessaustin 9y ago
        That's true for houses of a particular age and value. New stuff is all PEX, and has been for some time. Old enough houses would have been cast iron. Cheaper houses (mobile homes, for example) were all PVC for a long time. I had to dig up and repair a sewer pipe yesterday, and was somewhat surprised to find that it was made of clay tile.
        • icantdrive55 9y ago
          PEX is relatively new. There's still a lot of plumbers/HVAC guys who exclusively work with cooper, unless the owner wants PEX. How do I know? Contractor, and I have two rolls of Upunor on my garage, and still thinking (three years thinking) about doing my re-pipe in copper. Actually I have enough sticks of copper to do the job. Now--I just need the energy,mand motivation. Maybe today? (To anyone doing their own plumbing repairs. Do a bit at a time. Never just rip it all out.)
        • HillaryBriss 9y ago
          in Los Angeles county (and, I believe, LA City), clay pipe is still an approved material for sewer pipe laterals http://dpw.lacounty.gov/general/faq/index.cfm?Action=getAnswers&FaqID=IyNNMzMK http://dpw.lacounty.gov/general/faq/index.cfm?Action=getAnsw... http://library.amlegal.com/nxt/gateway.dll/California/lamc/municipalcode/chaptervipublicworksandproperty?f=templates$fn=default.htm$3.0$vid=amlegal:losangeles_ca_mc$anc=JD_64.17 http://library.amlegal.com/nxt/gateway.dll/California/lamc/m....
        • jessaustin 9y ago
          'icantdrive55 the thread is about water supply lines, not boilers or HVAC evaporator coils. I've dealt with a number of plumbers over the last several years, and not one wanted to use anything but PEX for supply lines. Actually a different preference would be a strike against any plumber I'd consider hiring for new work. Also you appear to be hellbanned.
  • ghvknvgvh 9y ago
    Note that the authors of the paper being discussed are Indian. Literally any way of having potable water is better than what they do now.
• mirimir 9y ago
  I suspect that outcome depends on water pH and temperature. One doesn't use copper pots for cooking acidic tomato sauce, for example. Acidic well water corrodes copper plumbing.
• userbinator 9y ago
  Not surprising, there is no contradiction. Copper is toxic to many forms of life.
  • Filligree 9y ago
    I somehow got copper in my fish tank... Don't.
    • nxc18 9y ago
      Lots of fish medication is copper based due to antibacterial/anti-parasitic action. Real bad for invertebrates though.
      • Filligree 9y ago
        In retrospect, the dead snails should have been a sign. I got a lot more copper in the water than fish could survive. Fortunately there were no fish in it yet.
• whatupmiked 9y ago
  "Copper content (177±16 ppb) in water stored in copper pots was well within the permissible limits of the World Health Organization. Copper holds promise as a point-of-use solution for microbial purification of drinking-water, especially in developing countries."
  • Houshalter 9y ago
    Yeah but they didn't test waters of different ph levels. I'm not sure if that would be an issue though.
    • std_throwaway 9y ago
      It could be an exponential curve and also be influenced by other ions in the water.
  • std_throwaway 9y ago
    Safety standards aren't as black-and-white as the law. Some people will suffer way earlier than other people. Some people can tolerate some substances in way higher concentrations than the average person.
• m45t3r 9y ago
  Just remember the authors are suggesting copper pots for water storage in developing countries, where people have more chance of dying from diarrhea than from prolonged exposure to copper.
  • kpil 9y ago
    My water is delivered in copper tubes... It can't be that bad, can it?
    • other_herbert 9y ago
      It probably spends most of it's time in cast iron though and only the last hundred or so feet in copper... I'm in the same boat though
    • reality_czech 9y ago
      There is more information here: http://www.health.state.mn.us/divs/eh/water/factsheet/com/copper.html http://www.health.state.mn.us/divs/eh/water/factsheet/com/co... If you have old copper pipes you're probably fine. An oxide coating builds up on the pipes over time that prevents the release of copper. If you have a water filter you're probably fine (although check the particular filter to see what it removes.) You should have a water filter anyway if you live in any area that used to have industrial sites.
• manmal 9y ago
  Copper intake needs to be balanced out by zinc intake since they are antagonists regarding resorption in the intestines (This article says 1 copper to 15 zinc: http://www.livestrong.com/article/336425-side-effects-of-trace-mineral-supplements/ http://www.livestrong.com/article/336425-side-effects-of-tra...), so if you supplement a lot of zinc you might be fine using such a pot.
• pmoriarty 9y ago
  I store filtered drinking water in various plastic containers (often used juice bottles or the bottles that I boght store-bought water in). I wonder how health effects from the chemicals leeching in to my water from these plastic containers compare with the health effects from using copper containers, or perhaps ceramic/porcelain containers as those are supposed to be non-reactive.
  • vram22 9y ago
    I do that too, sometimes, particularly when on trips in rural / forest areas / resorts (refill the plastic bottle at the camp place or resort's restaurant with filtered water from a water purifier) but as a heuristic, to mitigate any possible effects of the plastic chemicals, I throw away the bottle after a week or two.
    • semi-extrinsic 9y ago
      Doesn't that do the opposite of what you intend? I imagine plastic stuff obviously leaching at a decaying rate.
      • vram22 9y ago
        Interesting point, hadn't thought of it in that way. My "logic" was (though not thought through rigorously) something like this, maybe: the plastic may decay more with time and with handling and exposure to sunlight, hence throw the bottle after a week.
  • anigbrowl 9y ago
    drop me a line at gmail, if you have the time.
• ska 9y ago
  Copper pots are used for cooking because of the superior heat transfer, but you are not cooking with copper directly. They are "tinned", and this coating needs upkeep. You can't really cook with it directly because it's too reactive with acidic foods.
  • justincormack 9y ago
    Modern ones are coated with stainless steel which needs no maintenance
    • ska 9y ago
      true, modern ones are electroplated - can still be called tinning in practice although that's inaccurate. It doesn't need anything like the same maintenace as old style. The point was more that nobody really cooks directly with copper, and did not historically.