Archived posting to the Leica Users Group, 1998/03/21
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]At 11:10 PM 20/03/98 -0600, you wrote: >At 12:39 AM 3/20/98 -0600, you wrote: > >>BTW, I have been using Gordon Hutchings' pyro developer sold by >>Photographer's Formulary with what I consider to be wonderful results. > >Ah, Pyro. No experience with that developer. I hear it's real sharp, but >it's quite toxic, no? > Quite toxic yes. It is absorbed very easily through the skin an mucous membranes. Its chemical by-products produced during developing are likely mutagenic and carcinogenic. Pyro developers can cause serious kidney problems and are suspected causes of other illnesses. Taken orally, the stuff can be fatal, especially in accidental use by children. Mixing the powder gives off gases which should not be inhaled. The dry powder itself is a fine dust and can mix with air and be inhaled. Very strict safety must be adhered to when using pyro developers in the darkroom. One of the most important of these to note is to use nitrile gloves, which are impervious to these chemicals. Vinyl gloves are not suitable. These are some of the reasons that I am very reluctant to try pyro developers. There are far safer chemicals available for film development which produce different, but equally pleasing effects. (My opinion here, no flame wars please.) Admittedly, some of the effects of pyro developers are not easily duplicated with conventional developers, particularly highlight separation. - -GH