Re: Clearing prints and asthma
Richard Knoppow (dickburk@ix.netcom.com)
Tue, 18 Nov 1997 16:23:31 -0800
At 09:14 PM 11/18/97 +0100, Hamish Stewart wrote:
>>Subject: Re: Clearing prints and asthma
>>Sent: 17/11/97 0:32
>>Received: 17/11/97 22:26
>>From: Sil Horwitz, silh@iag.net
>>To: keith@ccp.arizona.edu
>>CC: alt-photo-process-l@skyway.usask.ca
>>
>>At 03:05 PM 1997/11/16 -0700, Keith Schreiber wrote:
>>>I didn't think of it at the time, but we could have neutralized the
>>>acid with baking soda.
>>
>>Could be almost as bad - the combination produces carbon dioxide, which can
>>be toxic in an enclosed place.
>>
>I read these posts with interest, but have a specific questions regarding
>Sodium Metabisulfite, which I use for clearing Gum Prints. I can't find
>any info about the toxicity of this chemical. But last Saturday night,
>while I cleared a batch of around twenty prints, I could feel some
>irritation to the throat and nose from the fumes. Being silly I didn't
>even think to grab the respirator. The following day I had an intense
>cough and a running nose.
>
>Do you have any comments regarding this chemical - and yes next time I
>use the respirator.
>
>Cheers
>Hamish
>
Being a sometime asthmatic I was unaware that Carbon dixoide could set it
off in some people. Carbon dioxide is the gas in carbonated bevarages. I
am most sensitive to Sulfur dioxide, the rather sharp smelling gas emitted
by ordinary fixing baths. Presumably Sodium Metabisulfite could be a
source of this in combination with other chemicals.
----
Richard Knoppow
Los Angeles,Ca.
dickburk@ix.netcom.com