Thousands of German protesters marched in Berlin on Saturday to demand a change in farming methods and vent their anger at a food scandal in which cancer-causing dioxin was found in some eggs, poultry and pork.

The scandal, caused by contaminated animal feed, has outraged consumers, triggered international health alerts and hit sales of German eggs and meat.

Organizers said 22,000 people took part in the demonstration, entitled “We are sick of it. No to genetic engineering, animal factories and dumping exports.” Onlookers put the turnout at close to 10,000.