I would expect that mining, leather-producing and dye-producing areas may very well have seen similar types of toxic waste leading to negative health outcomes even before large scale industrialization. And the areas downstream.

Here's an example of a mine that has had toxic runoff likely for millenia: https://en.wikipedia.org/wiki/Rio_Tinto_(river) at least partly due to human mining activity. I would expect that people living downstream of the mine would have negative health outcomes, possibly without being aware.

Before the industrial revolution, the primary way to refine gold from diffuse ore was to dissolve the gold in mercury, separate the amalgam, and then boil out the mercury to leave the gold behind. In large-scale mining, this resulted in local air pollution levels that were horrifying even when compared to the worst unmitigated industrial revolution era sites. Entire communities would get mercury poisoning from the air they breathed.

Certain biocides were a problem:

https://en.wikipedia.org/wiki/Bordeaux_mixture

(This one was invented after the Industrial Revolution started but it was used far away from most factories.)

Preindustrial cities were population sinks due to communicable diseases.

Go far enough back and no one lived long enough to get cancer.

I would expect any medieval lead and gold mines surrounding to be horribly unhealthy.