New Cyanotype/ toxicity

Terry King ( 101522.2625@compuserve.com)
Sun, 12 January 1997 6:47 AM

Message text written by John Barnier
>Ammonium dichromate is a listed human carcinogen, hazard rating 4
(extreme)
in the MSDS and best avoided, if possible. (However, this doesn't inhibit
the Gum Bichromate printers!)<

Nor should it.

Ammonium dichromate used sensibly implies no greater risk of cancer than a
walk to the car. Whereas ferri can be very poisonous if acccidentally
mixed with a strong acid.

I tend to go a little OTT with students in order to underline the need for
care. But we should be careful not to be alarmist. We should also be
careful where, and I am not referring to Mike, one suspects that someone
has an ax to grind.

Terry King

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