Just a side comment that I'm somewhat bemused by all this concern for photo chemical exposure.
I spent hours nearly daily for YEARS, starting around age 10 or 11 (after having just been a frequent studio visitor until then), in a tiny film darkroom with no ventilation and standing tanks of DK-50 and hypo. Our larger paper darkroom had no ventilation either. We didn't ever wear gloves, our hands were in the soup all the time - my dad's nails and hands were often stained brown from litho developer.
And all that second-hand smoke: Mom smoked cigs nonstop, as did lots of customers and friends who stopped by daily. Again, no real ventilation, just a fan at the front of the store and a bathroom window at the back... and they were only used in summer. By modern standards, it was a "dangerous" place to spend your childhood.
So now I'm 68 years old, with no lung issues or any other syndrome that can be traced to all that chemical exposure. Just sayin'...
Picture: at the studio in 1957, Mom pregnant with my sister... and besides all the daily chemical exposure, she was still smoking and drinking (like most 50s moms). Yet we both turned out healthy!