Q. I had a question regarding mushroom compost that I just purchased for our vegetable garden. After adding many bags of mushroom compost to the top soil, I noticed that one of the components was peanut meal. I have a daughter with peanut allergy. I am assuming I need to shovel all the dirt out and not let her eat anything that we grow in that area. I can't find any information on this topic, and also wonder about other produce/mushrooms that may be grown in this medium. I don't think I've ever seen produce or mushrooms with a may contain peanut" label."
A. The contaminiation of soils with food ingredients is not rare in agriculture, and fortunately no reports of food reactions from the inclusion of these allergens in compost media have thus far been published. Direct contamination of the foods present in the area is, however, possible. Washing foods does not ensure the elimination of contaminating food allergens in the soil. Also boiling or roasting is not completely safe when considering heat-resistant contaminating allergens such as peanut allergens. In this case we suggest having your daughter avoid eating vegetable foods present in the field at the time of the fertilization. However, it is not necessary to avoid foods grown in the garden, if they are washed well.