Effects of various vacuum cleaners on the airborne content of major cat allergen (Fel d 1)

Background It has been shown that a vacuum cleaner (VC) can increase airborne cat allergen levels. This study aimed to compare the degree of leakage of airborne Fel d 1 levels among five different VCs, both under laboratory conditions and in an apartment with cats. Methods Three of the VCs were marketed as antiallergic: a HEPA filter VC (VC A), a water impingement and HEPA filter VC (VC B), and a foam fabric filter VC (VC C). The other two were standard VCs: VC D and VC E, VCs were tested in a 20 m(3), airtight, experimental room and in a 53 m(3) living room in an apartment with three cats. Air was sampled with a glass-fiber filter and an impinger at 20 l/min for 30 min before, during, and after vacuuming. Airborne Fel d 1 was measured with a two-site monoclonal ELISA assay. Results In the experimental room, no airborne Fel d 1 level was measured before using the VCs. After introducing a dust sample containing Fel d 1 in the VCs, we found that VCs A, B, and E did not provoke any increase in airborne Fel d 1. In contrast, VCs C and D significantly increased airborne Fel d 1 levels (GM: 4.9 and 5.3 ng/m(3), respectively). In the apartment, all VCs induced an increase in airborne Fel d 1, which was carried by particles greater than 5 mu m. However, VCs C and D provoked significantly greater increases in airborne Fel d 1 than VCs A, B, and E (P=0.0001). Conclusions Our results suggest that: 1) The two VCs with leakage in the experimental room had greater leakages in the apartment. 2) In the apartment with cats, all VCs provoked increases in airborne Fel d 1, primarily carried by large particles. 3) Given the increased marketing of "antiallergic" VCs, further studies are needed to standardize methods for testing airborne allergen leakage by VCs.