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copper goooood! campylobacter baaad! ugh!

updated sun 15 may 05


Steve Slatin on fri 13 may 05

Lee ---

Actually, I understand your point perfectly -- copper
kills living things. On this we are in agreement.
Arsenic will also kill many water-borne bacteria,
given sufficient concentrations. I wouldn't want to
see it in glazes, though.

To oversimplify, your argument is that certain glazes
can put heavy metals into your food supply, which may
kill certain bacteria, and you wish to use this to
ameliorate background bacteria. My argument is that
there are better ways to kill the bacteria, and those
ways you don't need to worry about poisoning youself
or others.

If you are worried about campylobacter, don't eat raw
chicken -- a simple fix (you only need to cook to 180
F; it'll still be juicy). The only other source I can
think of for campylobacter is unpasturized milk, which
isn't available in the US (I know nothing about food
availability in Japan -- is raw milk sold?). If you
want more copper in your diet, you can take a
supplement (though insufficient dietary copper is
extremely rare except for premature infants). With a
supplement you can control the amount of copper you
are adding to your diet.

Increasing your consumption of any metal in a
relatively random, uncontrollable way, with the use of
leaching glazes with heavy metal content in functional
ware just isn't the best way to address the problem of
dietary deficiencies or bacterial contamination, IMO.

We deal with potentially contaminated water supplies
with chlorine treatment precisely because the chlorine
dissipates. Copper doesn't. It's not a wise way to
treat water, especially given that copper that isn't
bound in proteins is toxic. (IIRC, virtually all
dietary copper comes to you already bound.)

It's not that I don't see what you're going after,
Lee. I just think there are better ways to get there.

Best wishes -- Steve Slatin

--- Lee Love wrote:

> Steve, this would totally defeat the antibacterial
> properties of the
> copper glaze. It makes no sense. What we are looking
> at is an ability to
> control the release of copper into water.

Steve Slatin --

Sera que ela mexe o chocalho ou o chocalho e que mexe com ela

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Lee Love on sat 14 may 05

Steve Slatin wrote:

>Lee ---
>Actually, I understand your point perfectly -- copper
>kills living things. On this we are in agreement.
>Arsenic will also kill many water-borne bacteria,
>given sufficient concentrations. I wouldn't want to
>see it in glazes, though.
This would be funny if it weren't so sad.

Tell me, how much daily arsenic does the human body require?

Copper is an essential element. The daily copper requirement has been
estimated at 30 micrograms/kg of
body weight for an adult. That means you or I need about almost
200micrograms every day..

copper is an essential trace element involved in :
-fundamental cellular respiration,
-free radical defense,
-connective tissue synthesis,
-iron metabolism,

What are the side effects of a arsenic difenciency?

Copper deficiencies are : individuals with diets deficient in copper
often exhibit anemia, cardiac abnormalities such as blood vessel and
heart rupture, abnormal EKG's and have elevated levels of serum
cholesterol, triglycerides and glucose. A lifetime of marginal diet
copper in humans is thought to lead to heart disease. Copper deficiency
has been observed in premature infants and infants suffering from
malnutrition. Overt symptoms in adults are rare, but may occur with long
term shortage or, possibly, in those who consume zinc supplements for a
period of time.

>It's not that I don't see what you're going after,
>Lee. I just think there are better ways to get there.
In the example I have been using: switching back to copper from plastic,
is the BEST way to deal with the problems plastic water containers have
caused.. But if metal containers are not affordable, controlled soluble
copper glazed ceramics could take their place.

In the original study, they tested for copper toxicity. The scientist
explained that only dietarily required amounts of copper was leached
into the water. With glazed ceramics, the copper release could be tuned
to the optimal amount. Ceramic water containers or cisterns lined with
ceramic tile could go a long way in helping provide safe water in the
3rd world.

李 Lee Love 大
愛      鱗
in Mashiko, Japan Visual Bookmarks Zen and Craft

Lee Love on sat 14 may 05

Steve Slatin wrote:

>I've got lots of copper-bearing glazes, and I do the
>home-test regularly, and use liner glazes where
>appropriate. I'd do the same for my dog, if I had a

Steve, this would totally defeat the antibacterial properties of the
copper glaze. It makes no sense. What we are looking at is an ability to
control the release of copper into water. This is an big advantage over
copper metal containers. Just try the lemon test on a copper bowl. I
have, and the copper metal is more reactive than any copper glaze I have
tested. If we want to provide nutritional zinc, this can also be added
to the glaze. Personally, I take a zinc supplement everyday as
protection against heavy metals like lead.

We may see problems with people changing over to plastic water pipes in
new homes, replacing copper pipes. The other aspect of the study said
showed that the big problem with plastic is when it is in the dark. An
alternative method of treating the water was to put clear plastic
containers of water in the sun. They said that the sun's heat provided
similar protection as the copper water containers, but in the house in
the dark, copper water storage containers was the best answer.

But like I said, ceramic storage, using a copper glaze that is
specifically formulated to leach the optimal amount of copper, might
would be much more effective than copper metal containers. Of course,
the lemon test makes absolutely no sense in this situation, because we
WANT leaching for its beneficial effects, and also because we are
talking about water containers and not lemonade containers.

More research needs to be done related to these recent
discoveries. We need to stop trying to control people with fear. We
never make rational choices when we are motivated by fear. If our minds
are open, we can use something that we initially think of as a fault, as
an asset.

We may be able to use the leaching quality of copper glazes to
help protect people's health. Maybe we need more copper liner glazes
that release a controlled amount of copper.

Please check out this article:

Full article here:

Antimicrobial activity of copper surfaces against suspensions of
Salmonella enterica and Campylobacter jejuni
Gustavo Faúndez , Miriam Troncoso , Paola Navarrete and Guillermo Figueroa
Laboratory of Microbiology, Institute of Nutrition and Food Technology,
University of Chile. Macul 5540 Santiago, Chile


Salmonella enterica and Campylobacter jejuni are amongst the more
prevalent bacterial pathogens that cause foodborne diseases. These
microorganisms are common contaminants of poultry and poultry products.
This study was aimed to evaluate the antibacterial activity of metallic
copper surfaces on these important enteropathogens, and to determine the
potential acquisition of copper by food exposed to this metal.


The antibacterial activity of copper surfaces was evaluated overlying
them with suspensions of 106 CFU/ml of S. enterica and C. jejuni.
Bacterial counts obtained after 0, 2, 4 and 8 hours at 10°C and 25°C
were compared with those obtained in stainless steel and a synthetic
polymer as control surfaces. The results showed that when these
enteropathogens were kept in contact with copper a significant
antibacterial activity was noted, on the contrary when the same load of
pathogen suspensions were tested over the control surfaces it was found
that the bacterial counts remained unchanged or even increased with
time. The potential acquisition of copper by food exposed to this
surface was also evaluated. Meat exposed for one hour to a copper
surface adsorbed residual copper in a time dependant manner.


These results shows that metallic copper surfaces have an antibacterial
activity against S. enterica and C. jejuni and suggest its potential
application as an inhibitory agent in the various stages of the food
processing operations.

Full article here:

Another interesting article. Copper protects against viral agents like

This article says copper may be effective as an antiviral agent and may
even deactivate HIV-1.

Abstract found here:

Putting copper into action: copper-impregnated products with potent
biocidal activities
Gadi Borkow and Jeffrey Gabbay

E-mail contact:

Copper ions, either alone or in copper complexes, have been used for
centuries to disinfect liquids, solids, and human tissue. Today copper
is used as a water purifier, algaecide, fungicide, nematocide,
molluscicide, and antibacterial and antifouling agent. Copper also
displays potent antiviral activity. We hypothesized that introducing
copper into clothing, bedding, and other articles would provide them
with biocidal properties. A durable platform technology has been
developed that introduces copper into cotton fibers, latex, and other
polymeric materials. This study demonstrates the broad-spectrum
antimicrobial (antibacterial, antiviral, antifungal) and antimite
activities of copper-impregnated fibers and polyester products. This
technology enabled the production of antiviral gloves and filters (which
deactivate HIV-1 and other viruses), antibacterial self-sterilizing
fabrics (which kill antibiotic-resistant bacteria, including
methicillin-resistant Staphylococcus aureus and vancomycin-resistant
Enterococci), antifungal socks (which alleviate symptoms of athlete's
foot), and anti-dust mite mattress covers (which reduce mite-related
allergies). These products did not have skin-sensitizing properties, as
determined by guine pig maximization and rabbit skin irritation tests.
Our study demonstrates the potential use of copper in new applications.
These applications address medical issues of the greatest importance,
such as viral transmissions; nosocomial, or healthcare-associated,
infections; and the spread of antibiotic-resistant bacteria.

Abstract found here:

李 Lee Love 大
愛      鱗
in Mashiko, Japan Visual Bookmarks Zen and Craft