Some milk powders contain five veterinary drugs and meat-based meals - especially chicken - had up to 10 different drugs.
A loophole in the European Commission's control of pesticides has allowed the drugs to make their way into powders and foods. Existing regulations control the use of pesticides and drugs in cereal-based foods for children and babies, but they don't extend to animal-based products.
The drugs have been detected for the first time by researchers from the University of Almeria in Spain who used a new monitoring technology that involves chromatography and spectrometry.
The researchers say the amounts detected are very small, and probably harmless, but they are concerned about the build-up over time and the multiple drugs an immature immune system is dealing with.
(Source: Food Chemistry, 2012; 132: 2171-80).