Occupational sensitization to storage mites in the personnel of a water-damaged grocery store

To investigate the occupational exposure and sensitization to storage mites (SM) in sales staff working in a moisture-damaged and three healthy reference buildings.

The study population consisted of the entire personnel (n=12) in the moisture-damaged grocery store. They all suffered from persistent upper respiratory tract symptoms. Twelve (in results 11) symptom-free controls working in three healthy reference groceries were matched with age, sex and occupation. Dust samples from each building were examined for mites. The clinical study consisted of otorhinolaryngological examination and determination of IgE reactivity. Specific serum IgE antibodies were measured against three SMs and two house dust mites (HDM). Skin prick tests (SPT) were made to the same five mites and to five common aeroallergens. If sensitization to any of the SMs was detected, a nasal provocation test (NPT) was performed.

SMs were found in all buildings. In all, seven cases and four control subjects showed IgE-mediated reactivity. Sensitization to mites was detected in six cases and in three controls and in 2/12 and 3/11 this was the only IgE antibody response observed. In addition, one case and one control subject were sensitized to common aeroallergens. NPT with SMs was positive in four cases and in one control.

In grocery stores, the personnel are exposed to SMs. The risk of sensitization to mites is obvious and an IgE response can occur without any reactivity to common aeroallergens. SM allergy may in some cases explain the chronic rhinitis related to moisture-damaged buildings.