Composition of cyanotype wash water?

Sparrow.jpg

A
Sparrow.jpg

  • 1
  • 0
  • 50
Orlovka river valley

A
Orlovka river valley

  • 6
  • 0
  • 107
Norfolk coast - 2

A
Norfolk coast - 2

  • 5
  • 1
  • 97
In the Vondelpark

A
In the Vondelpark

  • 4
  • 3
  • 183
Cascade

A
Cascade

  • sly
  • May 22, 2025
  • 9
  • 6
  • 154

Recent Classifieds

Forum statistics

Threads
197,857
Messages
2,765,540
Members
99,487
Latest member
Nigel Dear
Recent bookmarks
0

pdeeh

Member
Joined
Jun 8, 2012
Messages
4,765
Location
UK
Format
Multi Format
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?
 
Joined
Dec 10, 2009
Messages
6,297
Format
Multi Format
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

Member
Joined
Nov 30, 2005
Messages
16,421
Location
La-la-land
Format
Multi Format
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.
 
OP
OP
pdeeh

pdeeh

Member
Joined
Jun 8, 2012
Messages
4,765
Location
UK
Format
Multi Format
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
 
Joined
Dec 10, 2009
Messages
6,297
Format
Multi Format
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.
 
OP
OP
pdeeh

pdeeh

Member
Joined
Jun 8, 2012
Messages
4,765
Location
UK
Format
Multi Format
All the materials will be pre-prepared, and anyway the only person handling anything will be me.
 

Gerald C Koch

Member
Joined
Jul 12, 2010
Messages
8,131
Location
Southern USA
Format
Multi Format
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.
 
Last edited by a moderator:

Wayne

Member
Joined
Jul 8, 2005
Messages
3,583
Location
USA
Format
Large Format
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.
 

removed account4

Subscriber
Joined
Jun 21, 2003
Messages
29,833
Format
Hybrid
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
 
Last edited by a moderator:
OP
OP
pdeeh

pdeeh

Member
Joined
Jun 8, 2012
Messages
4,765
Location
UK
Format
Multi Format
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.
 
OP
OP
pdeeh

pdeeh

Member
Joined
Jun 8, 2012
Messages
4,765
Location
UK
Format
Multi Format
I deleted my post. I sometimes fail to remember that there are actually some people who take these sorts of concerns dead seriously. I'm sorry. My "agenda" is to simply enjoy a basically harmless hobby. I was never a molecule counter. I have to continuously remember that this is a worldwide site and not just an american one. In Europe, they have totally strapped themselves down with rules, and in America, we're not there yet totally, only headed that way and pouring on the coal to get there.
I have to bang my head against the wall very often to wake up and remember there are actually people who believe this stuff and worry about it. You see it as "political agenda", which was the furthest thing from my mind. I think of the freedom of enjoying making a few harmless prints and suspending them in a stream to wash out. To you in the UK, it's politics, as is seemingly everything. To me living in the middle of Nowhere USA, it's not harming anybody or anything. It's hard to comprehend that in Europe, you can really get in trouble for something like this. Sorry.
It's been 23 years since I lived in the big city. The environmental paranoia washes out over time; fades away.
The forum asked for a casting of a vote basically. My vote is to make your 2 or 3 little prints, wash them in the stream, and have fun.
Maybe I don't belong on this site. Maybe another note from Sean will end it. Just damn well don't ever say I didn't contribute more than my share of helpful and learned repair and basic procedural text while I was here. You can push your little complaint button now. It's the triangle one at the bottom left (I think. I don't use it myself). Thought policing is not my gig.


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

Moderator
Moderator
Joined
Apr 24, 2005
Messages
52,183
Location
Delta, BC Canada
Format
Medium Format
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.
 
Photrio.com contains affiliate links to products. We may receive a commission for purchases made through these links.
To read our full affiliate disclosure statement please click Here.

PHOTRIO PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Ilford ADOX Freestyle Photographic Stearman Press Weldon Color Lab Blue Moon Camera & Machine
Top Bottom