Re: Pyro and gloves

Richard Sullivan (richsul@roadrunner.com)
Mon, 26 Jan 1998 15:47:14 -0700

Pyro is toxic. It takes about 2 grams estimated to kill a man. Estimated I
assume, because they've not tried any real testing to find out ... I hope!.
However it is nasty, but it is not as nasty as many make out. My Merck
Index says: "death has occured through percutaneous absorption", though I
would have to imagine that one would nearly have to bathe in it in order to
absorb enough to amount to 1-2 grams worth. This was probably some form of
industrial exposure. The Merck also says "Application to large extensive
areas of skin should be avoided." It stains skin real bad, so I think you
will have a fairly good idea of how much exposure you are getting. I've
heard tell in the old days one could spot a photographer by her black
fingernails, today it just may mean that the bearer is a fan of some rock
group.

DIck Arentz, who at one time was a surgeon, gave me some advice about
gloves. He says sometimes gloves are actually more dangeous than not. What
can happen, is that a pinhole can occur, allowing the nasty stuff to get
inside the glove and you won't be aware that it has leaked into the glove.
The gloves keep it at body temp and in close wet contact to the skin.
Nothing could be worse.

I don't see any practical way to do tray developed pyro without wearing
gloves, unless your goal is to look like an old timey photog and risk life
and limb in the process. The nitrile gloves sound like a good bet, though I
would not be too prone to lose any sleep over using regular latex gloves
for developing a 7 minute pyro run. On the other hand, at that price, why
not get a 100 box of the good ones.

--Dick Sullivan

>Pyro is extremely toxic and not just any glove will work. Latex gloves may
>be permeable to the pyro. Nitrile gloves may work better. Below are some
>comments from another list server on using gloves with phenolic based
>developers (note: the writer had not tested pyro):
>-----------------
>......... Best Glove had no data on photographic chemicals in their
>files. They did NOT recommend the use of latex gloves with developers such
>as pyro. Their first choice would be their N-Dex nitrile gloves for short
>term intermittent contact. I have run a check on the N-Dex 7005 (4 mil
>nitrile industrial disposable) glove using a Q&D test procedure that they
>recommended for screening using Windisch modified catechol developer (and
>the catechol stock solution) and did not observe any break-through after 4
>hours. Looks like these gloves will work.
>
>Best has a web site (www.bestglove.com) with a listing of distributers of
>their gloves. The N-Dex 7005 list for about $15.00/box of 100 in Fischer
>Scientific.
>
>The test procedure that they suggested was to cut off a glove finger, turn
>it inside-out, fill with the test solution, and then close with a paper
>clip. Hang the filled glove finger in a 35mm film container that contains
>some distilled water and see if the pH of the water changes with time. If
>something is permeating the glove, the pH of the water should change. It is
>suggested to run a distilled water control to eliminate changes in water pH
>from the glove material.
>
>Following this procedure, the working strength Windsich developer (strongly
>basic but not measured - sodium hydroxide is the base) and the DI water
>control did not change the pH of the water on the outside (stayed at 5.5)
>for at least 4 hours. The catechol stock solution (pH 8.5) also did not
>change the water pH over about 2 hours and the test is continuing overnight.
>
>Hopefully this will be one way to minimize exposure to pyro and other
>phenolic based developers.
>Larry Gustafson
>gustafsl@ix.netcom.com
>

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