Four-year stability of Der p I in house dust under simulated domestic conditions in vitro.

For almost 4 years, the stability of Der p I was assessed by RAST inhibition in house-dust samples incubated under simulated domestic conditions (5 or 25 degrees C and 75% relative humidity). Der p I concentrations were determined before heating dust samples at 60 degrees C to kill the mites, and at 0, 6, 14, 21, and 47 months after heating. Heating at 60 degrees C for 24 h caused no significant change in Der p I concentration. After a 47-month incubation under simulated domestic conditions, reduction of Der p I was still not obvious. It is concluded that even after extermination of mites, home textiles remain allergen reservoirs for an extended period of time. Avoidance schemes should take this into account.