House dust mite allergen levels in individual bedding components in New Zealand.
OBJECTIVE
House dust mite allergen (Der p 1) levels are high in New Zealand and bedding Der p 1 levels have been shown to be associated with the clinical severity of asthma. The aim of this study was to measure Der p 1 levels in synthetic and feather duvets and other individual bedding items, and to examine factors affecting these levels.


METHODS
Reservoir dust samples were collected and analysed for Der p 1 content by ELISA from 65 duvets, 81 pillows, and 65 mattresses of 34 children and 31 adults in 34 households.


RESULTS
Der p 1 geometric mean levels (95% confidence interval) were: 13.4 microg/g (9.5-18.9) in pillows; 29.4 microg/g (19.8-43.5) in duvets; and 53.8 microg/g (39.4-73.4) in mattresses. Synthetic pillows and duvets yielded significantly more Der p 1 than feather pillows and duvets (about 7-fold and 15-fold respectively). The presence of under-bedding resulted in significantly higher pillow and duvet Der p 1 levels. Mattresses >10 years old had significantly higher Der p 1 levels.


CONCLUSIONS
Synthetic pillows and duvets contain higher levels of Der p 1 than feather pillows and duvets. Advise for house dust mite sensitized individuals to use synthetic bedding does not prevent house dust mite allergen exposure.
Mills
Sarah
S
Department of Public Health, Wellington School of Medicine and Health Sciences.
Siebers
Robert
R
Wickens
Kristin
K
Crane
Julian
J
Purdie
Gordon
G
Fitzharris
Penny
P
D000485:Allergens / Q000032:analysis*; D000818:Animals; D001512:Bedding and Linens / Q000469:parasitology*; D004391:Dust; D008925:Mites / Q000276:immunology*; D009520:New Zealand
D000485:Allergens; D004391:Dust