HOUSE-DUST MITE AND CAT ALLERGEN IN DIFFERENT INDOOR ENVIRONMENTS

Allergy to house dust mites (HDM) and domestic pets is a major cause o f asthma. People in developed countries spend more than 90% of their t ime indoors. We have measured levels of HDM allergen Der p I and cat a llergen Eel d I in public buildings and public transport. Dust samples were collected by vacuuming a 1 m(2) area for 2 min from five schools , six hotels, four cinemas, six pubs, three buses, two trains and 12 d omestic households without a cat. Der p I and Eel d I were assayed wit h monoclonal antibodies in a two-site immunometric ELISA. Der p I conc entration was significantly higher in the private homes than in compar able sites in public places except for cinema seats (where high values were found) compared with domestic sofas. Der p I > 2000 ng/g of fine dust was found in 30% of the upholstered seats, 9% having a concentra tion > 10 000 ng/g. Fel d I levels were significantly higher in the du st from upholstered seats (geometric mean 14.88 mu g/g) than in carpet ed floors (geometric mean 0.73 mu g/g), and in public places than in p rivate homes. Eel d I > 8 mu g/g was found in 79% of the upholstered s eats or furniture sampled in public buildings or public transport. In conclusion, upholstered seats from public buildings and public transpo rt constitute an allergen reservoir for continuous contamination of th e indoor environment which could compromise the effects of allergen av oidance employed at home.