[skahde]

[...] as such authors like Anchell & Troop would have access to a wide variety of sources.

Question is why didn't they check them? Hydroquionone and Pyrogallol have more or less identical toxicity and cancerogenicity if you have a look at the MSDS.

However they were not publishing a scientific or academic paper so had no call to cite sources.

They certainly were not obligated to give a proof but in this case they were not able to give one in the first place as their statment is plain wrong. There is quite a number of rather bold statements in the photographic literature where there is no kind of proof given but which are in contradiction to well documented work others did. My personal conclusion is to rather ask for proof than taking for granted that some highly regarded source may not give false information in one place or another (and they inevitably do!).

At the end of the day it is our negatives, prints or even health which may take harm or your time and money wasted and in such a situation it's IMHO not clever to just rely on someone elses word.

best

Stefan