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Thread: pyro developer, but which?

  1. #181
    Roger Cole's Avatar
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    Re: pyro developer, but which?

    I don't hear anyone saying to blend oil and cadmium pigments with your fingers. I do hear people questioning wearing gloves for doing things like rotary and tank processing, even with pyro. In my case, I wasn't even questioning that very much, but rather those who indicated gloves for just the usual MQ or PQ developers, acetic acid and fixer, in rotary or tank processing or printing with tongs.

    There are degrees of risk, and unfortunately it isn't always possible to accurately asses them, so we have to work with the info we have. It seems there's enough evidence that pyrogallol and pyrocatechin are more dangerous than most other developing agents (metol, phenidone, ascorbic acid etc.) that metol is much more like to cause contact dermatitis than phenidone etc. Oh, and fixer, particularly used fixer containing silver, shouldn't be ingested.

    Some are only going to feel comfortable wearing gloves for all darkroom work, and that's ok. As I said, I use them for mixing chemicals and would seriously consider using them, probably would, if I were using pyro, but I haven't so far used them for rotary and tank processing with MQ or PQ developers, nor for printing with tongs. (I did use them for Ilfochrome then called Cibachrome, back in the late 70s when I noticed that spilling a drop of the bleach on a concrete floor sizzled! To be fair that risk was probably "just" that of a chemical burn - unpleasant but not long term deadly, but it persuaded me to use gloves for that stuff.)

  2. #182
    Drew Wiley
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    Re: pyro developer, but which?

    Roger - that fizz from Ciba bleach wasn't innocuous. The main ingredient was conc
    sulfuric acid! It can easily burn your skin and destroy your lungs if inhaled. Another
    reason to read the warning sheets before mixing this or that. Have a friend who once
    ran a big Ciba lab with over 200 hundered gals of bleach in replenishment tank. Cost
    his several hundred thousand dollars to repair the plumbing before he could sell the
    bldg, and he had ten years of medical work including repeated surgeries to remove
    scar tissue before his lungs were halfway back to normal. Another lab owner couldn't
    even enter his own place of business due to sensitization. The hazmat and zoning issues alone were a major headache. Fortunately, for us small volume one-shot drum
    users of Ciba, all we've got to do is drain the bleach into a plastic bucket with a little
    baking soda at the bottom, and it's instantly neutralized. Plus good fume extraction or
    ventilation (I run the drum on a cart outdoors). I would never, ever let color chemcials
    touch my skin, although Ciba fixer isn't much different from non-hardening ordinary
    b&w fixers. The stop bath I use for RA4 doesn't any higher concentration of acetic acid than the vinegar used for salad dressing. But since I dilute it from glacial acetic acid, I better know the difference!

  3. #183

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    Re: pyro developer, but which?

    Ian,

    That's just my point, catechol and pyrogallol are used for relatively non-serious medical treatments, and used topically, ie applied directly to the skin, in much higher concentrations than those used in developers. Misrepresenting the risks does nothing to enlighten darkroom workers.

    Pyrogallol as a treatment for lung cancer:

    http://www.ncbi.nlm.nih.gov/pubmed/19233505

    Lifetime dermal exposure of mice and rabbits to low doses of pyrogallol did not induce
    toxic effects.
    http://www.qualityhealth.com/health-...yrogallol-skin

    http://www.deepdyve.com/lp/sage/fina...lol-4Kd0SeaG1q

    http://cat.inist.fr/?aModele=afficheN&cpsidt=20544959

    There seems to be some evidence that pyrogallol is useful in many different forms of medical treatment, and is safe to use in cosmetics. I don't drink pyrogallol, or inject it, or even soak in it, and I don't panic when I get a few drops of a weak solution on my hands. I do wash my hands after a processing session. Maybe I'm being terribly reckless, but no one in the medical field seems to think so.

  4. #184

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    Re: pyro developer, but which?

    Drew,

    I'm beginning to be grateful we're not personally acquainted; it seems everyone you've ever known has fallen to some form of chemical exposure.

  5. #185
    Drew Wiley
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    Re: pyro developer, but which?

    Jay - you're referencing do-it-yourself snakeoil sites, not medical literature. You can find sites like that that tell you how to smoke vanadium. You are not doing anyone a favor by pooh-poohing known chemical hazards. Yeah, I once had a kid working here
    with a liver deficiency, who would end up in the emergency ward if he ate a Big Mac
    due to the preservatives in it. Most people are more likely to die from eating too many
    Big Macs and resultant obesity. Drinking a Coke would kill him. I once sat on a plane next to a Coca Cola exec. My wife asked her if she got her soda free. She said she wouldn't drink the stuff herself because all the ingredients were shipped hazmat. Well I'm not afraid of a soda now and then, but wouldn't want the original conc carbonic acid to even touch my skin. My wife has had several patients just the last few weeks
    who tried to bootleg a cure for this and that and now are in very real trouble, facing
    major remedial action.

  6. #186
    Drew Wiley
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    Re: pyro developer, but which?

    Just saw your last post jay. My experience and personal contacts are not coincidental.
    At one time everything within walking distance of my office was ringed by industrial
    mfg sites, including paint factories. Now all of them have been kicked out of town due
    to environmental concerns, and pharmaceutical companies and breweries have taken
    over, and a lot of restaurant and studios. I know a lot of artists working in many kinds
    of media - was talking to a remarkable one half hour ago, trying to help him with a
    fabrication issue. When I was younger, I could have gone into public health and then
    onto the EPA. Glad I didn't - my friends there exploded with estoteric multiple cancers
    from merely monitoring illegal pesticide use in this state; dead illegal farm workers were
    sometimes found in the fields (touching a single drop of Parathion is fatal). I routinely
    talk to university and rescue medics, and of course, have had several family members
    involved in specialized medicine, including my own wife, who works in reconstructive
    plastic surgery and encounters many strange forms of cancer. The lead surgeon goes
    to Vietnam to operate on some of the hundreds of thousands of children with birth
    defects from agent orange. The oldest employee in my company invented agent orange
    as an agricultural herbicide and has had all kinds of strange medical issues and treatments, but is thankfully still alive. Yeah, you can poo-poo that these kinds of
    problems could have been caused by drinking orange juice, but for some reason dioxins
    are now completely banned from mfg in the US and most other countries. Coincidence?

  7. #187
    Roger Cole's Avatar
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    Re: pyro developer, but which?

    Drew - I didn't mean to imply that Ciba bleach was innocuous, only that spilling a bit on your skin from occasional use might burn you, but probably wouldn't give you cancer or Parkinson's or whatever. And I never inhaled much of it, as you say. I also didn't have 200 gallons, and I used the neutralizer or baking soda per instructions.

    The fixer pretty much was BW rapid fixer, or close enough that some of us just starting buying the bleach. You could use BW print developer and fixer just fine, but you needed that narsty bleach.

    As I mentioned before, normal RA4 stop bath isn't any higher concentration. For the Tetanal room temperature RA 4 I used to use, they recommended double BW strength. It nearly choked me out of the darkroom, but it seemed to be something released when the developer was carried over (stronger developer for room temperature, I'd think - I've heard you can simply use RA4 replinisher for this.) I changed to a citric acid stop and for whatever reason, that fixed the problem. At least it didn't smell nearly as bad and I didn't get a sore throat anymore. I can't say for sure that nothing toxic was released, of course.

  8. #188
    IanG's Avatar
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    Re: pyro developer, but which?

    Nothing I said agreed with your point, just the opposite.

    There's plenty of scientific & medical evidence that professional darkroom workers prior to WWII suffered from an numbers of ailments & complaints as well as then unexplainable sicknesses.

    As I pointed out earlier that changed post WWII with a switch away from chemistry using Pyrogallol, Pyrocatechin and Amidol because smaller formats needed finer grain developers and could be mechanically processed.

    You van use out of context web pages to claim these substances are safe thats not the medical and scientific view even today.

    Ian

    Quote Originally Posted by Jay DeFehr View Post
    Ian,

    That's just my point, catechol and pyrogallol are used for relatively non-serious medical treatments, and used topically, ie applied directly to the skin, in much higher concentrations than those used in developers. Misrepresenting the risks does nothing to enlighten darkroom workers.

    Pyrogallol as a treatment for lung cancer:

    http://www.ncbi.nlm.nih.gov/pubmed/19233505



    http://www.qualityhealth.com/health-...yrogallol-skin

    http://www.deepdyve.com/lp/sage/fina...lol-4Kd0SeaG1q

    http://cat.inist.fr/?aModele=afficheN&cpsidt=20544959

    There seems to be some evidence that pyrogallol is useful in many different forms of medical treatment, and is safe to use in cosmetics. I don't drink pyrogallol, or inject it, or even soak in it, and I don't panic when I get a few drops of a weak solution on my hands. I do wash my hands after a processing session. Maybe I'm being terribly reckless, but no one in the medical field seems to think so.

  9. #189
    Drew Wiley
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    Re: pyro developer, but which?

    Roger - I really don't know what the thing is with RA4. It's probably some minor ingredient. I have my suspicions. Lab owners sometimes got sick. I can work with
    RA4 for about two weeks with no problem, then wham, I get sensitive, get a sore
    throat, and catch a cold or whatever respiratory thing is going around. Even an organic vapor respirator doesn't help, so it must be a sensitization issue in very small dosages. Ciba is much easier to control because it's mainly a simple acid issue. I ration my printmaking very careful and do the actual chemical processing outdoors. My 30x40drum processor is rigged up on wheels. I have a nice level concrete pad for it, and the wind direction is predictable. I'd like to install a 40" Kreonite roller-transport processor for RA4, but it would be in a special outbuilding with a ventilation system completely separate from my main lab. The only color process I'll do in my black-and-white darkroom is dye transfer printing. Of course, most folks these days solve this whole
    kind of problem by printing color via inkjet.

  10. #190

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    Re: pyro developer, but which?

    Drew,

    You seem quite happy to provide nothing more than anecdotes, but the research on pyrogallol for treatment of lung and other cancers is current and credible. I don't think the Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan is a snake oil site. Pyrogallol is currently used as a treatment for eczema and psoriasis, and approved by the FDA. Not snake oil. The International Journal of Toxicology from the American College of Toxicology is surely medical literature, as is the International Journal of Molecular Medicine. Did you even open the links?

    Ian,

    I know you disagreed. You wrote:

    There's a huge difference in using controlled does of Pyrogallol for serious medical conditions and uncontrolled absorption through the skin which amy build up over time.
    But my point was that pyro is used for relatively non-threatening conditions like eczema and psoriasis, as a topical medication, to be absorbed through the skin, and I quoted a study that found no toxic effect from dermal contact with pyrogallol over a lifetime in rats. This is current research, and the web pages are very much in context if we're discussing the toxicity of pyrogallol. The FDA has found pyrogallol safe for use in cosmetics. That's the current medical view. No one is saying pyrogallol is harmless, just that its toxicity is limited, and there doesn't seem to be any credible evidence that its use in the darkroom represents a special hazard. "I know a guy who tasted rubber when he spilled a drop of pyro on his arm" is not credible evidence. Your example of pre vs post WWII darkrooms confuses correlation with causation, and is evidence of exactly nothing, supported by exactly nothing.

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