National Dyes Company and Affiliates (Italian: Azienda Coloranti Nazionali e Affini), more commonly known as the ACNA, was the first Italian chemical company, active from 1929 to 1999 in Cengio (main plant), as well as in Cesano Maderno and Rho, although it traces back to 1882 under different names. The company was best known for the pollution of land and waters related to its production of dyes earning it the nickname of "the poison factory" which would see it brought before the Italian government.