Mite and pet allergen exposure in Brazilian private cars

Background The role of mite and pet allergens in the development of allergic diseases has been recognized for many years. Objective To determine mite ( Dermatophagoides pteronyssinus [Der p 1] and Dermatophagoides farinae [Der f 1]), cat ( Felis domesticus [Fel d 1]), and dog ( Canis familiaris [Can f 1]) allergen levels in Brazilian private cars. Methods Mite, cat, and dog allergens were measured in dust samples collected from 60 upholstered seats of private vehicles using enzyme-linked immunosorbent assays. Results Mean levels of Der p 1 (0.24 μg/g of dust; range, 0.0–2.05 μg/g of dust) and Der f 1 (0.29 μg/g of dust; range, 0.06–2.07 μg/g of dust) were extremely low in most dust samples analyzed. In contrast, sensitizing mean levels of Can f 1 (1.51 μg/g of dust; range, 0.14–30.96 μg/g of dust) and Fel d 1 (0.43 μg/g of dust; range, 0.02-5.75 μg/g of dust) were observed in 32 (53%) and 12 (20%) samples, respectively. Mean Can f 1 levels were significantly higher in cars whose owners kept dogs at home (3.27 μg/g of dust) than in those without pets (0.57 μg/g of dust; P = .008). There were no significant differences in allergen levels regarding the age of the vehicle or the number of users and whether the owners transport pets inside the vehicles. Conclusions Private cars constitute an important pet, but not mite, allergen reservoir for continuous contamination of the indoor environment. Pet allergens may be present even in cars whose owners do not have pets. Effective measures to reduce allergen exposure in cars should be taken routinely, especially for pet-allergic patients.