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#1 Judy Athey

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Posted 09 June 2013 - 10:09 AM

Is there a way to test if pottery is food safe?

#2 JBaymore

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Posted 09 June 2013 - 10:22 AM

The term "food safe" has no reall "legal" definition. What most people mean is, "will this surface leach out anything harmful into food"?


While there are what might be called "home tests" ...such as using household vinegar and looking for surface or color changes, the only REAL way to know FOR SURE is having laboratory standard leach tests done. These tests are mildly destructive... if the surface is not stable. Meaning that it COULD potentially alter the piece a little.

Additionally, you need to know what you are testing FOR. The only lechates regulated in the USA (and the Statge of Calif.) are lead and cadmium compounds. Ther are others that COULD potentially be of concern.

Lab testing will cost you about $30-40 for tha basic test...and about an additional $10-30 per compound that you wish to have tested for. Plus the shipping of the piece back and forth.

When compared to drinking out of plastic bottles, microwaving in plastic containers , and using plastic food wraps..... usually pottery is of little concern. But few think of what the plastics are getting into foods.

best,

.............john
John Baymore
Immediate Past President; Potters Council
Professor of Ceramics; New Hampshire Insitute of Art

http://www.JohnBaymore.com

#3 Benzine

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Posted 09 June 2013 - 02:34 PM

The term "food safe" has no reall "legal" definition. What most people mean is, "will this surface leach out anything harmful into food"?


While there are what might be called "home tests" ...such as using household vinegar and looking for surface or color changes, the only REAL way to know FOR SURE is having laboratory standard leach tests done. These tests are mildly destructive... if the surface is not stable. Meaning that it COULD potentially alter the piece a little.

Additionally, you need to know what you are testing FOR. The only lechates regulated in the USA (and the Statge of Calif.) are lead and cadmium compounds. Ther are others that COULD potentially be of concern.

Lab testing will cost you about $30-40 for tha basic test...and about an additional $10-30 per compound that you wish to have tested for. Plus the shipping of the piece back and forth.

When compared to drinking out of plastic bottles, microwaving in plastic containers , and using plastic food wraps..... usually pottery is of little concern. But few think of what the plastics are getting into foods.

best,

.............john


Pretty much everything we humans do, is killing us slowly.

I guess the goal, is to not add to the list of things that is expediting the process.
"Anything worth believing, is worth questioning"

#4 Iforgot

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Posted 10 June 2013 - 12:54 AM

The term "food safe" has no reall "legal" definition. What most people mean is, "will this surface leach out anything harmful into food"?


While there are what might be called "home tests" ...such as using household vinegar and looking for surface or color changes, the only REAL way to know FOR SURE is having laboratory standard leach tests done. These tests are mildly destructive... if the surface is not stable. Meaning that it COULD potentially alter the piece a little.

Additionally, you need to know what you are testing FOR. The only lechates regulated in the USA (and the Statge of Calif.) are lead and cadmium compounds. Ther are others that COULD potentially be of concern.

Lab testing will cost you about $30-40 for tha basic test...and about an additional $10-30 per compound that you wish to have tested for. Plus the shipping of the piece back and forth.

When compared to drinking out of plastic bottles, microwaving in plastic containers , and using plastic food wraps..... usually pottery is of little concern. But few think of what the plastics are getting into foods.

best,

.............john


Well, in that case, if a glaze recipe dose not contain lead, cadmium, barium, manganese, or any other harmful material then is having leach testing for lead, cadmium, and the like pointless?

Darrel
Derek VonDrehle

Raku, Pit fired, Majolica, and Stoneware ceramic artisit

#5 JBaymore

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Posted 10 June 2013 - 09:22 AM

Well, in that case, if a glaze recipe dose not contain lead, cadmium, barium, manganese, or any other harmful material then is having leach testing for lead, cadmium, and the like pointless?


Darrel,

Yes.

best,

.................john
John Baymore
Immediate Past President; Potters Council
Professor of Ceramics; New Hampshire Insitute of Art

http://www.JohnBaymore.com




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