Composition of cyanotype wash water?

pdeeh

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I've been asked to collaborate with a friend on a community arts event held on public (city council) property.

Part of what's envisaged is making photograms on-site during the event using traditional cyanotype.

This of course means washing the prints, and thus disposal of the rinse water becomes an issue.

As we know, cyanotype chemicals are very safe and of low toxicity, but nevertheless a statement in advance will have to be made to the responsible authority disclosing details of the activity and any environmental/h&s impact will have to be assessed.

So ... I'd like to know just what is contained in the wash water from a cyanotype.

Obviously ferricyanide and ferric ammonium citrate in very dilute amounts, but presumably there are other chemicals which are a product of the reduction process.

I'm less than clear about these other products, and that's what I'd like help with.

Gerald? Rudy? Loris?
 
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I think if it's the old recipe for cyanotype that is potassium ferricyanide and ammonium ferric citrate, it's ok just to dump the water. Both ingredients are not very toxic. I've heard from a wine maker friend that they used to use potassium ferricyanide in wine making and ammonium ferric citrate is used in a Scottish soft drink called Ironbru. Please correct me if I'm wrong about the toxicity.
 

BrianShaw

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I always had the same impression. But I can't recall if it was just an impression or if I read it somewhere. Also, I assume that the chemistry remaining in the wash water is very dilute given the amount of water it takes to wash a print.
 
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pdeeh

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Excellent.
The venue is a public park, and as there is a stream running through it, we thought it might be nice to wash the prints in that.
The event is location.focused, and the artist concerned is not only doing a piece around wild plants (so a nice link to Anna Atkins) but has a physical problem with illness connected with exposure to uv ...
We'll see, it may yet not happen but I wanted to be prepared for the inevitable risk assessment
 
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For liability purposes, have the attendees wear gloves. In such a litigious age, I wouldn't leave anything to chance. Also, tell them to handle all chemicals with great care.
 
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pdeeh

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All the materials will be pre-prepared, and anyway the only person handling anything will be me.
 

Gerald C Koch

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I can see no problems. People who are unfamiliar with photography find it fascinating when an image appears. Perhaps you'll encourage some people to investigate analog photograph.
 
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Wayne

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I think you'd be crucified for washing prints in a park stream in the US, regardless of what is or isn't in the prints. There are "chemicals" in there silly, and all "chemicals" are known to be bad.
 

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pdeeh

from what i remember the slurry contains iron and water ..
i contacted the folks who make " sun print paper" here in the states
it is classic cyanotype paper .. and it is made in california ... and
is labled by the state of california to be child friendly. when i called
they said the state's tests are pretty hard-core ( most hard-core in the states ).
i called/asked them because for a handful of years i have been doing classic cyanotype workshops
with grammar school kids ( 3rd grade-6th grade ) at a local school and like you, i wanted to make
sure what i was getting myself into.

yours sounds like a fun project !

john
 
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pdeeh

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APUGuser19, as so often your comments are not pertinent to the matter in hand, and serve only for you to bang the drum of your personal political agenda.

Please take your ideas to the soapbox or lounge rather than uselessly clutter up a thread where technical assistance is being sought.
 
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pdeeh

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your mea culpa is undermined by your making it in terms that serve only to restate your position, and is - at the very least - disingenuous.

As before, this sort of thing belongs elsewhere, not in technical threads where it adds nothing to the discussion.
 

MattKing

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I agree with pdeeh, but ....

It is certainly relevant if you want to reference what the official rules are.

And if you have the knowledge and expertise, to comment on whether they are appropriate, and if not, what would be.

Where I live, we are seeing a significant number salmon streams returning from being wastelands to being productive habitat for salmon. That is entirely due to the imposition of habitat preservation and restoration rules - both governments and not for profits have been very active, and a significant part of the progress has been due to restriction of the pollutants that had been dumped into the streams in the past.

There is still a huge amount of un-repaired damage and destruction, but the progress is meaningful. And it starts by people asking questions like the questions in this thread.
 
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