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In western nations, a big contributor to lead in blood is ceramic items.[1]

The 'clear' coating on the outside of cups, mugs, teapots, etc. often contains lead, and slightly acidic drinks or water will cause it to leach out. That has a much bigger impact than leaded paint, because you typically don't lick your paint.

Lead glaze is most often used in artisan, novelty or complex items, because the lead oxide acts as a flux which allows the glazing to be done at a lower temperature, which is necessary when glazing complex objects which would otherwise melt or crack during the glazing process. Lead is also far easier to use, because it works over a wider temperature range, so if you do a "make your own pottery" day, you'll probably be using lead flux in your glaze.

[1]: https://www.efsa.europa.eu/sites/default/files/event/2005/af...



This is absolutely wild to me. BRB, investing in a borosilicate glass...


And decorative crystals, too. Beads, rhinestones, etc.

It's generally pretty harmless because the lead is so tightly bound into the material. You'd have to grind it to powder to get bad exposure... or maybe melt it (crystals usually have high melting points).

Still, they're slowly being phased out, mainly because of the reputation of lead, rather than a true health concern.


It should be very illegal to bring such raw materials on the market.


Lead is so important in making ceramics, there is nobody proposing to ban it. Instead, the main proposal is to require ceramics to be tested after manufacture to ensure that the dose of lead leached into any given food or drink is sufficiently low.

The main way that is achieved is by firing the ceramics at higher temperatures and longer to ensure the lead is better chemically bound to the rest of the pottery and leaches slower.


That sounds like very bad news to me. So now I have to trust whoever made the ceramics to not sacrifice this step, which I can't really check on my own.


Important in what way?


This is based on making pottery as a hobby: Most craft potters working in earthenware use lead glazes as the colour response is more appealing than what can easilly be achieved with other low-temperature fluxes. It's also more resistant to crazing, and for earthenware to be functional it's important the glaze doesn't craze significantly as earthenware is slightly porous- if the glaze is crazed then your coffee cup will leave a damp mark on the desk.

(Lead is not used on stoneware or porcelain.)




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