A friend of mine just came across a trove of family
photographs from this period and as he puts it:
"...in those days it was
customary to have your portrait taken and have them printed on postcards and
send them friends & relatives, we found many amazing beautiful portraits of
people we didn’t know. I shipped a bunch out and have them here now. The
question is that when I handle these photos from 1900 – 1920 my nostrils and
throat start to burn. Is there some chemical in these old prints that could be
hazardous?"