Fixer and the Environment

Discussion in 'Black and White' started by kathryn_treacy, Aug 18, 2016.

  1. That would be nice.

    I have recently done fixer tests on my current fixer but not on the ones on the top shelves of my garage no. I won't be able to get to it until the temperatures moderate a little so I can get out there and move a bunch of stuff to get a ladder to that high shelf. Plus the jugs are brown opaque jugs. Not sure how I'm going to see inside that. Maybe a really strong flashlight from the top or maybe holding it up to a really strong light?

    How long would that chemical process take to happen? How many years and would temperature factor in? It's still brutal here 85+ degrees and it's been getting cold in the winter too. Some of it is probably only a year or two old, and other bottles are much older.
  2. No silver flows out of a municipal treatment plant. All the silver in the fixer you discard will have been converted to silver sulfide, perhaps within 200 yards of your drain. Silver in some forms is toxic however this compound is inert. If the stuff tests positive for silver it is because the test reagent was nitric acid, it reduces this inert compound but nature can't. You all worried about the wrong thing. It's the fixer that liberates chlorine and causes the treatment plant to induce more chlorine. Do you think a home darkroom has any impact? It will be a thimble full in relationship to the volume coming in to the treatment plant. Such dilution is not detectable by any instrumentation I know of. I also know it will do no harm.
    ihordvoretskyi and Moving On like this.
  3. Hard to say how long. I've spent a lot of years working with replenished and regenerated chemical systems, and we just don't let those go bad. Essentially, thiosulfate systems can last for an indefinite time provided that you keep enough sulfite ion in there, and the pH is in an adequate range. The industry literature (and lore) says that higher temperatures and pH falling below about 4.0 are quick killers of thiosulfate (fixer) solutions, but I don't know anyone with first-hand knowledge of this. But if your old fixer was really decades old, I think it would have almost certainly have "sulfurized."

    If you can get to your jugs and decant a little off the top, you can try a clearing test.
  4. Vincent Peri

    Vincent Peri Metairie, LA

    Hmm... home darkroom...
    wash the fixer down the
    drain... done...
  5. That book was once a "bible" of sorts regarding photo effluent, so I was once pretty familiar with it, and will parse a bit for you. Check out page VI-21 regarding the toxicity of photographic silver:
    Regarding what happens at the POTW (sewage treatment plant):
    I'm guessing that this needs some translation. Essentially it is saying that the photographic silver is not very toxic at all, supporting what Alan has been suggesting.

    I should point out that these tests are for what they call "acute toxicity," roughly what happens in a short period of time, perhaps up to several months.
  6. Thanks for reviving this.
    This and the whole thread is a very timely and interesting thing to read. How do these numbers scale when one considers fiber based black and white paper?

    I wish my scale of potential output were as small as Carbon Dragon's but alas, it is not the case. For over a decade I had been looking for suitable space for a very capable fine art darkroom, 35mm, 120 and 4x5 film printed to up to 45" x 55". About 18 months ago, I closed on a house that allows me to have nearly 500 square feet in a finished basement. The location is great and price was not too bad for the area ( very expensive ).

    But there was a is on a septic system and we are not on city water but well water that is shared in an HOA. We had bad fires this year, my house was 1/3rd mile from the line and we were evacuated for a week. So now I am quickly becoming a water conservation guru. Both my 16x20 and 20x24 print washers have re-circulator pumps to conserve water. Both sinks have diverter valves to re-capture water and or chemistry. Only small amounts of Dektol and Xtol have gone into the drain thus far, no fixer though....but this is test volume, not production volume.

    As much as I love the space and the home, with film volumes in the hundreds of rolls / sheets a year and more concerning, long and large printing sessions, this is a pain in the rear.

    So as it stands right now, I have to recapture and pay for disposal of all of it and at peak volume, it could cost me well over $1,000 a year to do so. I am toying with the idea of partially evaporating the water component of it, neighbors are not that close.

    Anyway, as water scarcity becomes a bigger and bigger problem globally, this craft is going to be under a larger and larger magnifying glass. So I have written letters of concern to all the major players in analog regarding this.

    Anyway, here are the digs thus far, about 80% done:

    Darker.01.jpg Darker.02.jpg Darker.03.jpg
  7. Actually the big magnifying glass was applied, at least in the US, 'bout 30-some years ago. Kodak, Konica, and Fuji all had environmental specialists to help customers with their problems. In fact, this is when the so-called "washless" systems for color processing came about, to drastically reduce volumes of liquid to be hauled off by waste haulers. Plenty of research was done into ways to get "clean" effluent or minimize waste, even recycle water - then equipment makers, such as CPAC in NY state, would design equipment to use the new technologies. But when the huge processing volumes went away, so did the staff positions for environmental specialists.

    I'd say that your best bet is to look to your film and paper suppliers for expertise from their companies; I expect that you will have to pay for it. All things considered, $1,000 per year to have your silver-bearing wastes hauled and disposed of may not be a bad deal.

    I think it's a smart move to keep that silver-bearing waste out of your septic system, mainly because of the regulatory problems you might get into. I'd recommend that you keep good records on the disposal, just in case a future bureaucrat might set their sights on you.

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