One of the nastiest jobs in history was that of a tanner in medieval Europe. Tanners were responsible for turning animal hides into leather, but the process was revolting and dangerous. They soaked hides in vats of urine, animal dung, and decaying flesh to soften and clean them before treating them with harsh chemicals like lime. The stench was unbearable, attracting swarms of flies, and the constant contact with filth and toxic substances often led to infections and chemical burns. Because of t