Italian police said Monday they have seized 30 tons of Chinese-made steel that had been contaminated by a radioactive substance. The environmental protection police squad said the steel was destined for the industrial production of chimneys and pulleys, and long-term exposure could have been dangerous for workers handling it. Police said in a statement that the shipment had come from China's TISCO company and had arrived in the northern port town of La Spezia in May last year. The steel had been accidentally mixed during production with cobalt-60, a radioactive isotope of cobalt, police said. Officers seized it last week after radiation turned up in tests on metal scraps at companies across Italy that had used part of the shipment. China's exports have come under intense scrutiny in the past year after potentially deadly chemicals were found in goods including toothpaste, toys and seafood.