Abstract

Asthma caused by allergy to proteins from cereal grains is one of the most common types of occupational asthma (OA) worldwide and its prevalence does not appear to be declining. Baker's asthma is the most serious manifestation of occupational allergy among bakery workers, which develops after inhalational exposure to flour dust allergens encountered in the work environment. Exposure to cereal flours such as wheat and rye, as well as enzymes, has been reported to play an important role. However, more recently several other salt-soluble, insoluble proteins and recombinant allergens have been implicated. Exposure response studies have demonstrated consistent evidence that the risk of developing occupational allergy increases with allergen exposure, and this relationship is modified by atopic status. Despite the overwhelming evidence that workplace exposures to flour dust should be controlled, prevention strategies in bakeries appear not to have been very satisfactory. The review describes current regulatory standards and preventative strategies, noting that the South African exposure standards are not protective and do not follow international best practice. While total avoidance of flour dust exposure is not possible in bakeries, exposure reduction is the preferred pragmatic approach. Various exposure reduction strategies that have been recently reported in the literature are reviewed with a view to optimising preventive approaches.