I don't know what symptoms allergic reactions to different developers may cause. But I know that many people react to hydroqinone (spelling?) in developers. There are developers now that do not contain this harmful chemical:(posted 9363 days ago)For film: Kodak Xtol For paper: Agfa Neutol PLUS
Xtol is well documented by now and there is a lot of information on this film-developer on this site. Agfa Neutol PLUS, a paper-developer, seem to be less known and I haven't tried it myself. The only review I have read (in the German Color-Photo magazine) said that it was an excellent developer, however it produced a slightly cold tone (the opposite of Agfa Neutol WA, which however is an old developer that probably contains hydroqinone). If the motive should have a warm tone, it can be toned afterwards (howabout in that poisonous Rapid Selenium toner :^) Seriously, other toners are much less bad for the health, I think those are sulphur-based.