I ran across this graphic which describes the origins (and typical toxicity) of many materials that have been used across the centuries as dyes and pigments. (What’s the difference between a dye and a pigment, you say? Simply put, a dye imparts color to a substrate (cloth, hair, etc.) while a pigment consists of particles which are mixed into a carrier and coated onto a substrate (think paint.))
In any case, it’s an interesting stroll through arsenic-laced wallpaper, heavy metals, and ground-up mummies, leading to purple mauveine, the first synthetic dye, whose discovery by Joseph Perkin in 1856 started organic chemical synthesis–which itself leads to the modern pharmaceutical and chemical industries.
I hadn’t heard of the web comic before–Veritable Hokum–but it describes itself as “a comic about mostly history, maybe science, and possibly some other stuff too.”–so right up my alley. I foresee binge reading of its archives in my near future.