Exposure to indoor allergens in day-care facilities: Results from 2 North Carolina counties

Background: With 63% of US children under 5 years of age in regular child care, day-care facilities could be an important source of exposure to indoor allergens. Objective: This study examined levels of 7 indoor allergens in 89 day-care facilities in 2 North Carolina counties. Methods: At each facility, a questionnaire was administered, observations were made, and vacuumed dust samples were collected from carpeted and noncarpeted areas of one room. Allergen concentrations were measured with antibody-based ELISAs. Results: Each allergen was detected in a majority of facilities (52% to 100%). Geometric mean concentrations were 5.19 mu g/g for Alternaria alternata, 2.06 mu g/g for Can f 1, 1.43 mu g/g for Fel d 1, 0.21 U/g for Bla g 1, 0.20 mu g/g for Der p 1, 0.10 mu g/g for Der f 1, and 0.01 mu g/g for Mus m 1. Concentrations for 5 of the 7 allergens were not statistically different from concentrations found in southern US homes sampled in the National Survey of Lead and Allergens in Housing. In rooms with carpet and hard-surfaced flooring, levels of A alternata, Can f 1, Der f 1, Der p 1, and Fel d 1 were statistically higher on carpet. Conclusions: In this survey of day-care facilities in North Carolina, detectable levels of indoor allergens were commonly found. For many young children and day-care staff, day-care facilities might be a source of clinically relevant exposures to indoor allergens.