Lack of evidence of IgE allergic sensitisation from working with lactic acid bacteria in the dairy foods industry

Abstract

This research communication aimed to evaluate the level of immunoglobulin E from lactic acid bacteria (LAB) that are used in dairy industries. Previous studies have demonstrated that workers report symptoms of irritation and are frequently IgG-sensitised to LAB. Workers (n = 44) from a probiotic production unity and the control lab were seen by a medical practitioner and responded to an occupational questionnaire. Specific IgE by the DELFIA® technique against 6 strains of LAB were measured on 44 exposed workers and 31 controls sera. Levels of specific IgE were low and no difference was observed between the two groups. This lack of IgE response could be explained by a healthy worker effect, an efficient implementation of personal protective equipment or by an absence of allergic mechanisms to account for the self-reported irritative symptoms. Despite the high concentrations of LAB, preventive measures are effective enough to guarantee no allergic effect and to prevent other adverse health effects. The implementation of preventive measures to avoid or reduce exposure to dust of LAB, and more generally to milk powder, is recommended in all dairy industry.