[Nursery schools, a site for exposure to house dust mite allergens?].

In June 1988, 110 dust samples from carpets, cushions, mattresses and upholstered furniture were collected by vacuum cleaner in 33 municipal nursery schools. All samples were assessed with guanine test strips (Acarex). In all samples giving moderately or strongly positive results in these tests (guanine stages 2 and 3) and in 10 random samples each from of stages 1 (weakly positive) and 0 (negative), mites were counted by light microscope. In 36% of the nursery schools, objects with guanine stages 2 or 3 were found, which indicates a high allergen burden. The high guanine stages were found only in mattresses, cushions and upholstered furniture. Nursery schools can be source areas of significant allergen exposure relevant for children with dust mite allergies.