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I recently purchased a cast iron bread pan, and didn't see that it was made in China on the Amazon sales page. Oops. I saw it on the box and haven't opened it yet. I know there is a lot of concern when it comes to Chinese goods and heavy metals. I like heavy metal { \m/...(>.<)…\m/ }, but not in my food. So, is something like this safe? I Googled the question, but like with so many things it looks more like uninformed fear than anything else.

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I should have spent a bit more time searching. One of the searched results that looked like a fear video was actually the opposite. Here is some stuff from that video and comments.

First: Lead boils at about half the temperature that iron melts. So even if you start out with a mix of lead and iron, it won't last long. Second:

A bit of arithmetic: - Cast Iron Assay can expect Lead content to be 0.001 to 0.15%. (By weight or volume is not significant, see below) My 26.5 cm Chinese skillet, as yet unused (which is why I am researching) weighs 2.1 kg. At 0.15% that is a total lead content of 3.15g. Realistically, how much of that can ever get into the food? Cast iron density is around 6800 - 7800 kg/m3. At the higher figure this works out to a volume for my skillet of 2.1/7800 m^3 = 2.7 x 10^-4 m^3= 270cc. Ignoring the handle and sides, let us consider only the flat cooking surface diameter 20cm, and assume a depth of say 1mm available to leach the lead. Volume of a cylinder = pi r^2 x h = 3.14 x 10cm^2 x 0.1 = 31.4cc. Thus 31.4/270 x 100 = roughly 11.6%. 11.6/100x3.15 = 0.37g = 370μg of lead available. Lead toxicity is at about 10 μg/dL of blood. Average human blood volume is 500dL. So, if ALL the available lead in the pan was taken out AT ONCE, and you managed to absorb it ALL, just into your blood, , you would have a blood level of 370/500 = 0.74μg/dL, about 1/14th the toxic level, before your system kicked it out at around half per 30 days. Go figure.

--flamencoprof

So no, I don't need to worry.

edit: Hmm. The video's figures were wrong. Iron melts at about 1811K and lead boils at about 1749. Close but not quite. Still, from this source it seems that a typical blast furnace should still boil lead.

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    There are commercially made steels in which lead is intentionally added, eg steels meant for turning on a lathe - lo and behold, not all the lead is boiled out when making it. Also, not every mixture of materials can be divided by simple distillation (see eutectic alloy, see azeotrope...)... – rackandboneman Apr 27 '17 at 8:26
  • Sooo.... from that, is it safe or not, you just quoted the stuff but did not say decisively what it made you conclude. 'So I dont need to worry' but then an edit below. – redfox05 Aug 31 '17 at 20:30
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The melting point of lead (621°F), a boiling point of 3,164°F and starts to vaporize The point where Iron is ready to cast is 2300-2500.F doesn't come close to the point of stratification of the metals. It's all about the metal you start with in the first place. Chinese Cast Iron? Who knows

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