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Subject: Re: [Homebrew_PCBs] Re: Laser Printer Toner transfer with plain regular paper

From: Adam Seychell <adam_seychell@...>
Date: 2003-03-06

rolanyang wrote:
> Yea, from what I read, you just let the let the pump bubble/aerate
> the solution for a while, and then it changes back to the
> green color.... and it seems to work :)
>
> If this were to become popular, it would put those Ferric Chloride
> distributors out of business.
>
> Someone on the list mentioned earlier that they were hospitalized
> for copper poisoning. I am slightly concerned about the toxicity
> of the stuff. From the MSDS, it doesn't sound very toxic, but
> the fact that the guy was sick enough to be put in the hospital
> concerns me..
>
> ~Rolan


What he didn't mention was ∗HOW∗ he became intoxicated. I mean
was he drunk one day and his friends dared him to drink some
cupric chloride solution, or did he get a spec under his
fingernail and later got poisoned when he bit his fingernail.
Yes, I agree there is reason to be concerned, but no more so than
any copper compound which includes ∗ALL∗ copper etchants use for
PCB making. For a good understanding on the biochemical aspects
of copper see;

http://www.inchem.org/documents/jecfa/jecmono/v48aje06.htm

Fatal oral human dose is 200mg/kg bodyweight.

that translates to a 70kg person eating about 2 TABLESPOONS
(55grams) of copper sulfate.

Dietary copper intake is 0.05mg/kg bodyweight.