Abstract
Background: Laboratory animal workers face the risk of developing an IgE-associated respiratory allergy to airborne proteins such as Mus m 1. Approximately 15% of exposed employees will develop IgE sensitisation and 10% clinically apparent disease. We have recently embarked on a large study to gain a greater understanding of contemporary laboratory animal allergy (LAA) and determine whether we can devise a code of safe practice to prevent as far as possible the future occurrence of LAA.
Aim: To determine Mus m 1 personal exposure within an animal facility where mice are housed exclusively in individually ventilated cages (IVC).
Methods: Selected employees wore Casella Apex pumps (2L/min) to collect inhalable particulate onto fluoropore membrane (1µm), 25mm filters using IOM sampling heads. Eighty two filters were analysed for Mus m 1 using a commercial sandwich enzyme linked immunoassay (Indoor Biotechnology).
Results: The range of Mus m 1 levels within our samples varied from 0.00 – 66.33 ng/m3, with eleven (13%) samples having a Mus m 1 exposure level greater than 5 ng/m3. The variability represented different tasks carried out by the laboratory animal workers, but we also observed variability between samples from the same individual carrying out the same task on different days.
Conclusions: Despite the use of IVCs, which have been shown to reduce exposure to Mus m 1, a substantial proportion of exposures were higher than 5 ng/m3, a figure previously suggested to limit or reduce incidence of LAA. We will examine whether variation in working practices are responsible for high allergen levels.
- Copyright ©ERS 2015
