|The advent of feudalism in the Middle Ages did little to improve work
standards. Possibly the sole advancement of that time was the establishment of feudal
guilds which assisted ill workers and their families.
The study of occupational disease was virtually ignored until 1473 when Ulrich Ellenbog published his pamphlet on occupational diseases and injuries among gold miners. He also wrote about the toxic action of:
The field of industrial hygiene was boosted by his instruction in hygiene and other preventive measures.