The Child's Conception of Food: The Development of Contamination Sensitivity to "Disgusting" Substances.

When a disgusting substance comes in contact with an acceptable food, it renders that food unacceptable to almost all adults (trace contamination). In addition, some adults reject acceptable foods associated with, but not contacted by, a disgust substance (associational contamination; e.g., rejection of a favorite soup stirred with a brand new fly swatter). Previous work with children indicates that trace contamination responses do not appear in most children until the age of 7 or older and that associational contamination is rare before age 12. However, these conclusions were based on responses to stories. In the study presented here, we measured acceptability by the child's behavior toward objects (cookie, comb, and juice) that were actually contaminated with insects or human hair. The results confirm the prior findings as to the age of onset of both types of contamination and extend the range of contaminating substances studied to include human residues (in this case, hair). The onset of contamination responses may be influenced both by the achievement of a requisite level of cognitive development (appreciation of the particulate nature of matter, etc.) and by the prior establishment of a category of "disgust."