It leads to terminal lead poisoning. From 1860.
I had to look it up:
Snuff is a generic term for fine-ground, smokeless tobacco products. Originally, the term referred only to dry snuff – a fine tan dust popular in the eighteenth century. This is often called ‘Scotch Snuff’, a folk-etymology derivation of the scorching process used to dry the cured tobacco by the factory.
What is Snuff? | Wilsons & Co (sharrowmills.com)