Occupational seafood allergy: a review

Background-Recent years have seen increased levels of production and consum ption of seafood, leading to more frequent reporting of allergic reactions in occupational and domestic settings. This review focuses on occupational allergy in the fishing and seafood processing industry. Review-Workers involved in either manual or automated processing of crabs' prawns, mussels, fish, and fishmeal production are commonly exposed to vari ous constituents of seafood. Aerosolisation of seafood and cooking fluid du ring processing are potential occupational situations that could result in sensitisation through inhalation. There is great variability of aerosol exp osure within and among various jobs with reported allergen concentrations r anging from 0.001 to 5.061(mug/m(3)). Occupational dermal exposure occurs a s a result of unprotected handling of seafood and its byproducts. Occupatio nal allergies have been reported in workers exposed to arthropods (crustace ans), molluscs, pisces (bony fish) and other agents derived from seafood. T he prevalence of occupational asthma ranges from 7% to 36%, and for occupat ional protein contact dermatitis, from 3% to 11%. These health outcomes are mainly due to high molecular weight proteins in seafood causing an IgE med iated response. Cross reactivity between various species within a major sea food grouping also occurs. Limited evidence from dose-response relations in dicate that development of symptoms is related to duration or intensity of exposure. The evidence for atopy as a risk factor for occupational sensitis ation and asthma is supportive, whereas evidence for cigarette smoking is l imited. Disruption of the intact skin barrier seems to be an important adde d risk factor for occupational protein contact dermatitis. Conclusion-The range of allergic disease associated with occupational expos ure to crab is well characterised, whereas for other seafood agents the evi dence is somewhat limited. There is a need for further epidemiological stud ies to better characterise this risk. More detailed characterisation of spe cific protein antigens in aerosols and associated establishment of dose-res ponse relations for acute and chronic exposure to seafood; the respective r oles of skin contact and inhalational exposure in allergic sensitisation an d cross reactivity; and the contribution of host associated factors in the development of occupational seafood allergies are important areas for futur e research.