The bands, which are worth around €3 million, were confiscated from five warehouses in the Chinatown area of the northern city, Rai News reported on Thursday.
Police have warned that the elastic bands could contain high levels of carcinogens.
The bands, which are plaited together and decorated with charms to make bracelets, did not have a CE safety mark, which ensures that the product meets the requirements set by EU law.
Three people of Chinese nationality have been reported to police and fined €40,000.
Police have also informed the Italian Customs Office and the Internal Revenue Service of the illegal activity.
It’s the second seizure of this kind in Europe, after a similar incident in England, according to Rai News.
“It is clear that we are facing an organized supply chain that we are happy to have broken," local Safety Councillor Marco Granelli was quoted as saying.
Alarm bells were first raised about the dangers of the bands by a British laboratory tasked with testing the safety of jewellery.
In August the Birmingham Assay Office, a company which tests the safety of toys, issued a warning that the charms attached to the bands contained deadly levels of phthalates, which is classed as possibly carcinogenic.
While the legal limit for the chemical is 0.1 percent, some of the charms were found to contain a level of more than 50 percent.