DUST AND AIRBORNE EXPOSURE TO ALLERGENS DERIVED FROM COCKROACH (BLATTELLA-GERMANICA) IN LOW-COST PUBLIC-HOUSING IN STRASBOURG (FRANCE)

Background: Although a strong association between allergy to cockroach (CR) and asthma has been observed in the United States and Asia, ther e are little data about the extent of exposure to CR allergen in Europ e. Objective: To deter-mine the levels of CR allergens in dust samples from apartments in strasbourg and to determine the concentration and size of CR allergens in the air. Methods: Nine apartments in a public housing complex were chosen on the basis of visual evidence of CR infe station. Levels of CR allergens (Bla g 1 and Bla g 2) in kitchen and m attress dust samples were measured by immunoassay with the use of mono clonal antibodies. Air was sampled for 3 to 8 hours in the kitchen und er undisturbed conditions, during artificial disturbance and during no rmal domestic activity by using an impinger and a parallel glass fiber filter and at flow rates of 2 to 20 L/min. Airborne CR and mite aller gens were measured concurrently in the bedroom of one apartment before , during, and after artificial disturbance. Results: High levels of Bl a g 1 and Bla g 2 were found in kitchen dust from the nine apartments (geometric means of 3919 U/gm [range 530 to 14306 U/gm] and 497 U/gm [ range 73 to 1946 U/gm], respectively). Under undisturbed conditions, a irborne CR allergens were not detectable in any of the apartments. Dur ing vigorous artificial disturbance, Bin g I and Bla g 2 were detectab le in ab samples front seven apartments (geometric means of 4.5 U/m(3) [range 0.7 to 17.2 U/m(3)] and 1.0 U/m(3) [range 0.4 to 3.4 U/m(3)], respectively). Both allergens were predominantly collected on the firs t stage of the impinger; and 76% to 80% of the airborne allergen was a ssociated with particles greater than 10 mu m in diameter. The levels were significantly higher than those collected on the second or third stages of the impinger (p < 0.001). A comparison of the levels of mite and CR allergens showed that the airborne properties of these allerge ns were similar; that is, measurable only during disturbance and not d etectable 30 minutes after disturbance. Conclusion: Levels of CR aller gen in low-cost public housing in Strasbourg can be as high as ol high er than the levels measured in towns in the United States. CR allergen s become airborne during disturbance and are primarily associated with particles greater than 10 mu m in diameter. Patients with asthma livi ng in urban areas of Europe in housing prone to CR infestation should be evaluated for sensitization and exposure to CR allergens.