One of the main concerns regarding the use of insect-resistant transgenic crops is their potential detrimental effect on non-target organisms that fulfil important ecological functions. The potential effects on desirable non-target organisms are thus assessed as part of the environmental risk assessment prior to the commercial release of any novel transgenic crop. Aphids are abundant herbivores in most crops and are attacked by a range of specialist predators and parasitoids. We here show that aphids do not ingest considerable amounts of insecticidal proteins when feeding on Bt-transgenic crops. We argue that occasional reports of low concentrations of Bt Cry proteins in aphids can be explained by contamination of the samples. Consequently, antagonists that are specifically or predominantly attacking aphids are unlikely to be at risk because of limited exposure. Studies to support the environmental risk assessment should thus focus on species that are more likely to be exposed to the insecticidal compounds.