Many people with peanut allergy live in fear of exposure to a trace of this legume. And the parents of children who are allergic to peanuts are sometimes overwhelmed by the concern that a peanut-munching classmate may put their child in danger. But new research published in the Journal of Allergy and Clinical Immunology that shows that everyday soaps and cleansers can remove the peanut allergen, and that schools appear to be keeping school surfaces clean, may help ease their fears.
"There is a lot of concern, particularly for children in school and preschool, about the need for things like a peanut-free table in the cafeteria," said Robert A. Wood, senior author of the study and a professor of pediatrics at Johns Hopkins School of Medicine in Baltimore. "We wanted to look at what it would take to clean peanuts off a tabletop and off of hands, as well as how much peanut allergen might be found when sampling in schools and preschools."
For the 1.5 million Americans with peanut allergy, exposure to the allergen can lead to a range of reactions, from hives to a potentially life-threatening anaphylactic reaction that causes difficulty with breathing. While reactions are usually due to the ingestion of peanuts, there is concern, though not good scientific evidence, that even skin contact with peanuts or the inhalation of airborne peanut allergens can trigger a reaction.
To evaluate the effectiveness of various cleaning products in removing peanut allergens from surfaces, researchers spread a tablespoon of peanut butter across a tabletop and used different cleansers to remove it. They found that plain water, Formula 409 cleanser, Lysol sanitizing wipes and Target brand cleaner with bleach all eliminated the peanut allergen, but that dishwashing liquid was not effective. Researchers also found that it was fairly easy to remove peanut allergen from hands. While commercial cleansing wipes were the most effective cleanser, liquid soap and bar soap also worked well. Sanitizing gel, however, left allergen behind on six of 12 hands and plain water left allergen on three of 12 hands.
In another part of the study, six schools and preschools in the Baltimore area were randomly sampled for peanut allergen. No residue was found on the tables or desks, and traces of the peanut allergen were found on just one of the 13 water fountains sampled.
Dr. Wood called the results reassuring. "Peanut allergy completely dominates the lives of a lot of families," he said. "This study shows that if reasonable efforts are made to clean table tops and wash hands, there is very little chance of having an accidental exposure."