Exposure of workers to mites in Finnish groceries

We assessed the mite exposure of workers in Finnish groceries by collecting samples of settled dust in 5 different grocerys. Mites were counted and identified microscopically. Mite allergen (Der p 1 and Der f 1) content of dust was analyzed with 2-site ELISA. Mites were found in 20-100 % of the samples, both from storage and salesrooms. Seven samples (8 %) contained more than 100 mites per gram dust and 3 additional samples (6 %) more than 500 mites per gram dust, the suggested limits for mite sensitization and acute allergic symptoms, respectively. Most of the mites were storage mites belonging to Astigmata (Acaridae, Glycyphagidae) or Prostigmata (tarsonemids). House dust mites were found only occasionally. One dust sample out of 15 contained Der p 1, and none contained Der f 1.