Farms in Lower Saxony, Germany, have been banned from selling milk after it was discovered that their livestock were eating feed containing 30 times the acceptable limit of aflatoxin, according to reports.

The source of the contaminated feed was traced back to 10,000 metric tons of corn imported from Serbia, which was mixed into animal feed and delivered to 3,560 farms in Lower Saxony, including 938 dairy farms, said the state's Agriculture Ministry. Milk from cows which have ingested aflatoxin is considered to be particularly dangerous, as opposed to meat and eggs from chickens, pigs and cows fed the contaminated feed, which pose little risk to human health.

Animal feed manufacturers have said that the contaminated milk was diluted with milk from other farms and so posed no danger to consumers, said Bernhard Krüsken, spokesman for the German association of animal feed manufacturers. But criticism grew as the scale of the contamination became known.