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Originally Posted by reducereuserecycle  Here is another concern. When a piece of pottery containing lead (or any toxic contaminate for that matter) is fired in a kiln, a certain amount of the toxin will leach to the kiln and for the life of that kiln, it has the potential to release the toxin during the following firings and contaminate pieces that were not actually glazed with lead glazes. So, technically just because a handmade piece of pottery says "lead-free glaze" does not mean that some amounts of lead did not outgas onto it from the kiln during a firing. I am very leary of what I eat off of for this reason. It is hard to determine what is actually safe. The only way to guarentee that a handmade piece of pottery is foodsafe is to know that nothing toxic has EVER been fired in that kiln. Most of my ceramiscist friends would sneak lead-glazed pieces into the kilns even though they were not allowing lead glazes at our university. Our kilns were already contaminated anyhow, but it goes to show that no kiln can be considered safe unless it is used by a small amount of ceramicists that bought/built the kiln new and really have never fired any toxic glazed pieces in it.
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The cooperative studio I work out of has bought multiple new kilns since I have been a member, and they are not allowed to use lead there. It is misleading to assume that everyone is working with contaminated kilns. For About 30 years now, ceramicists have been warned not to use lead, so it is not a common practice in the US. Afterall, the person most likely to get lead poisoning is the potter because they have contact with it in dust forms. According to
http://www.cfsan.fda.gov/~dms/fdalead.html "While adults absorb about 11 percent of lead reaching the digestive tract, children may absorb 30 to 75 percent. When lead is inhaled, up to 50 percent is absorbed, but less than 1 percent of lead is absorbed when it comes in contact with the skin." So, if there lead is present in the dinnerware, it is still a very minor risk compared to lead in other sources, like paint or soil.
Plus, when high fired opposed to low fired, the lead does not leach unless the glaze surface has been abraided. I looked at California's list of acceptable commerical brands and it was huge. I will take ceramic plates any day over plastic or other alternatives. According to
http://www.cfsan.fda.gov/~dms/fdalead.html, "Bolger adds that even with these pieces, risk varies. "A plate coming in brief contact with food is not an issue," he says, "but storage of food in such a bowl or pitcher is a risk." It's especially wise to avoid storing acidic foods like juice and vinegar in ceramicware, as acids promote lead leaching."
: These paint-your-own places are ALL over in my area. All I see are kids in there with their moms painting pottery to take home and eat off of. I drink out of one of the mugs every day. I can't believe they would put children at risk by lying like this 
