BRUSSELS — European Union officials have demanded tests on buffalo mozzarella amid fears that Italy’s famed cheese has become contaminated by carcinogenic chemicals linked to the country’s rubbish crisis.

Health officials are awaiting test samples taken from Campania’s buffalo herds and have set a deadline of April 1 for the Italian food safety authorities to comply.

Italy’s agriculture minister, Paolo De Castro, yesterday criticized a ban by South Korea on mozzarella imports after the Seoul government claimed dioxins had been found in 29 samples of the cheese.

“It would be a mistake to infer anything from this and to create a dangerous panic,” he said. He said it would “unfairly compromise the image of an excellent product and which risks becoming heavily penalized in Italy and abroad.”

E.U. officials are concerned that southern Italy’s Mafia-linked rubbish disposal crisis, which has left thousands of tons of waste uncollected or dumped in illegal landfill sites, has led to the contamination of water buffalo herds, which produce the best milk for mozzarella. Last week, Italian environmental officials placed 66 buffalo herds in quarantine due to unusually high levels of toxic dioxin chemicals.