A century later, Richard von Volkmann reported increased skin cancers in workers of the coal tar industry of Germany, and by the early 1900s increased rates of cancer from exposure to soot and coal tar was widely accepted.
Un século máis tarde, Richard von Volkmann informou dun incremento dos cancros de pel entre os obreiros da industria do alcatrán de hulla en Alemaña, e a inicios da década de 1900 era amplamente aceptado que a exposición á feluxe e alcatrán de hulla incementaba as taxas de cancro.