Prevalence (%) of allergen types in home dust samples from Cuernavaca, Morelos Mexico. (A) Proportion of allergens above of the detectable level. The cutoff point was based on the lowest limit of detection for each allergen: 12 ng/g for Der p 1, Der f 1, and Can f 1; 4 ng/g for Der p 2, Fel d 1, and Rat n 1; 1.2 ng/g for Mus m 1; and 98 ng/g for Bla g 2. (B) Number of allergens exceeding detectable levels in homes. For the overall allergen exposure, we assessed how many allergens exceeded detection limits and allergen-specific thresholds for detectable levels in each home.