Some 30 buffalo farms around Naples began work again Tuesday after tests showed their milk did not contain cancer-forming dioxins.
Health officials said 17 samples from mozzarella plants, which get their milk from the 30 farms, had been cleared.
The consortium which guarantees Campania buffalo mozzarella said it had unconfirmed reports that ''the vast majority'' of samples from the 256 plants where production has been halted were OK.
But food hygiene inspectors said it would take until Friday to have ''the full picture''.
Italy's mozzarella dioxin scare appeared to be receding as South Korea became the latest country to lift a sales ban.
But, in a separate case, levels of dioxin 35 times above normal were found in mothers' milk near a large steel plant at Taranto, southern Italy.
Farms in the vicinity of the Ilva plant have been closed as tests are carried out on local milk and dairy products.