History of Identification of Human Carcinogens ramazzini 1700 nuns breast cancer pott 1775 chimney sweeps scrotal cancer . Rehn 1895 dye industry workers bladder cancer Unna 1894 sunlight exposure skin cancer .Yamagiwa 1915 animal model skin tumorsHistory of Identification of Human Carcinogens •Ramazzini 1700 nuns breast cancer •Pott 1775 chimney sweeps scrotal cancer •Rehn 1895 dye industry workers bladder cancer •Unna 1894 sunlight exposure skin cancer •Yamagiwa 1915 animal model skin tumors