Cleaning cyanotype glassware?

[athanasius80]

I needed an extra glass when I was coating cyanotypes, so I grabbed a tumbler from the kitchen. Seeing it now, there's some dried blue solution left at the bottom of the glass. If I scrub it out and run it through the dishwasher is it safe to drink from?

Thanks!

 

[Marco B]

Cyanotype blue is composed of the "Prussian blue" pigment, a pigment also used in artist oil and acrylic paints, and invented as a new synthetic color pigment in the 19th century, one of the first chemically manufactured pigments used in paints. It isn't any highly toxic compound, essentailly composed of iron, carbon and nitrogen:

http://en.wikipedia.org/wiki/Prussian_blue
http://painting.about.com/cs/colourtheory/a/prussianblue.htm

Just wash it off, and if you have difficulty getting it of the glass, use some soda. Alkaline conditions will destroy the pigment, and should allow it to wash it off.

 

[Akki14]

I use a magic eraser (cut to size) to scrub the blue stuff I missed on my plastic graduated cylinder. Slightly abrasive. WHO sets the safe limit of prussian blue for a standard man to be something like 6grams. There's probably barely 0.1g on your glass. I would still advise against not mixing your foodware and your photoware though...

 

[Marco B]

I would still advise against not mixing your foodware and your photoware though...

Wise words in general, but Prussian blue has some nice stories to it.

As the Wikipedia articles says, it seems a "cure" for some kinds of heavy metal poisoning (Thallium specifically):
"It has been used as an antidote for certain kinds of heavy metal poisoning."

And: Dead Link Removed

Also worthwhile reading, is this article about the supposed "inventor" of Prussian Blue, "Johann Konrad Dippel":

http://www.cabinetmagazine.org/issues/31/pendle.php

Very amusing , I love the detail of how Johann Konrad Dippel was born in Castle Frankenstein :devil: and text like:

"Perhaps it was little surprise that within two years of moving to Strasbourg, where he had hoped to make his name in theological study, he had killed a man in a duel and fled back to Giessen.
"

And:
"Fittingly for a mixture of blood and iron, one of its first uses was to dye the uniforms of the Prussian Army, from which it gained its more familiar name."

Marco