In a subset of study homes, we used a standard
HUD method44 to assess exposure to
asthma-related allergens (dust mite, cockroach,
and mouse) through floor dust vacuum sampling
in the study child’s bedroom, living room,
and kitchen at baseline and exit visits. We
marked an area of approximately 3 sq ft adjacent
to upholstered furniture in the living room and
adjacent to and slightly under the bed in the
child’s bedroom, with each area vacuumed for
approximately 2 minutes. On bare floors, we
sampled more than one 3 sq ft area if needed to
collect sufficient dust for analysis. In the
kitchen, we sampled the floor perimeter along
the base of walls, appliances, and cabinets.
Laboratory analysis was by the Multiplex
Array for Indoor Allergen (MARIA) method
(Indoor Biotechnologies, Charlottesville, VA) for
dust mite allergens Der f1 and Der p1, Mite
Group 2 (combination of Der f2 and Der p2),
cockroach allergen Bla g2, and mouse allergen
Mus m1.