Re: plea to chemists

From: Richard Knoppow ^lt;>
Date: 11/11/05-03:43:00 AM Z
Message-id: <003a01c5e6a4$51dead20$c5fb5142@VALUED20606295>

----- Original Message -----
From: "Christina Z. Anderson" <>
To: "Alt List" <>
Sent: Thursday, November 10, 2005 5:47 PM
Subject: plea to chemists

> For the first time since I started teaching Experimental
> Photography, Safety and Risk Management has more or less
> told me today that I can no longer teach the mordancage
> process because of the chance of toxic gas, etc.
> I have talked with 6 different chemists over the last
> three weeks about whether toxic gas is released with the
> process. None of them have said so. But Safety and Risk
> Management does.
> I am NOT pouring glacial acetic acid directly on copper
> chloride. Here is the formula:
> Into 750 ml water pour 80ml glacial acetic acid.
> Add 30g copper chloride and stir.
> Add water to 1000ml..
> At time of use, this "Part A" is mixed in equal amounts
> with 20v hydrogen peroxide. The print is submerged in
> this for a few minutes, rinsed (but not always well) and
> then redeveloped into developer or toner, such as thiourea
> or sepia.
> The last person I talked to said that in the dilution I am
> using, the acetic acid will reduce the copper chloride to
> a salt, not a toxic gas (e.g. chlorine).
> What do you chemists think?? Jon Bailey, Judy Siegel,
> etc., you've taught this process before; what do you know?
> The students are very unhappy at this turn of events, as
> you can imagine. But I would not want to teach something
> that has this kind of danger to students, either. So I
> really need to know the bottom line here...and it is
> frustrating that there is conflicting information between
> chemists and Safety and Risk Management. That said, SRM
> is the final word, so I would have to convince them they
> are wrong.
> I just don't have any close chemist friends short of this
> list :)
> Thanks in advance,
> Chris
   It would be interesting to know if the Risk Management
department has any chemists working for it. I bet they are
all lawyers. Probably they are concerned mostly with
avoiding legal jeopardy. Can you approach these people at
all? I would ask what evidence they have that the procedures
are too dangerous. If there opinion is based on some book
about chemical hazards its probably wrong.
   Possibly Ruyji Suzuki could help. I think he has enough
academic qualifications and enough experience with photo
chemistry to voice an opinion that might carry some weight
or at least lead you in the right direction.

   If you were ever into science fiction find a very old
Jack Williamson story called _With Folded Hands_.

Richard Knoppow
Los Angeles, CA, USA
Received on Fri Nov 11 03:43:20 2005

This archive was generated by hypermail 2.1.8 : 12/01/05-02:04:49 PM Z CST