Molecular and immunological approaches in quantifying the air-borne food allergen tropomyosin in crab processing facilities

Tropomyosin is a cross-reactive allergenic protein present in ingested shellfish species. Exposure and sensitization to this protein via inhalation is particularly important in the crustacean processing industry where workers are continuously exposed to the aerosolized form of this allergen. The aim of this study was to develop an antibody-based immunoassay to enable the specific and sensitive quantification of aerosolized tropomyosin present in the environment of two crab processing facilities. Anti-tropomyosin antibody was generated in rabbits against tropomyosins from four different crustacean species. These antibodies were purified using recombinant tropomyosin using an immuno-affinity column. The recombinant tropomyosin was also used as an allergen standard for the sandwich ELISA. In order to quantify aerosolized tropomyosin, air collection was performed in the personal breathing zone of 80 workers during two crab processing activities, edible crab (Cancer pagurus) and king crab (Paralithodes camtschaticus) using polytetrafluoroethylene filters. The purified antibody was able to detect tropomyosin selectively from different crustaceans but not from vertebrate sources. The limit of detection (LOD) for the developed sandwich ELISA was 60picogram/m(3) and limit of quantitation (LOQ) 100picogram/m(3). Immunoassay validation was based on linearity (R(2) 0.999), matrix interference test (78.8±6.5%), intra-assay CV (9.8%) and inter-assay CV (11%). The novel immunoassay was able to successfully identify working activities, which generated low, medium or high concentrations of the aerosolized food allergen. We describe an IgG antibody-based immunoassay for quantification of the major food allergen tropomyosin, with high sensitivity and specificity. This modified immunological approach can be adapted for the detection of other aerosolized food allergens, assisting in the identification of high-risk allergen exposure areas in the food industry

Exposure to Bioaerosols during Fish Processing on Board Norwegian Fishing Trawlers

Objectives:The main objective was to gain more knowledge on exposure to bioaerosols in the processing area on board fishing trawlers. Methods: Exposure sampling was carried out during the work shifts when processing fish in the processing area on board five deep-sea fishing trawlers (trawlers 1–5). Exposure samples were collected from 64 fishermen breathing zone and from stationary sampling stations on board five deep-sea fishing trawlers (1–5). Trawlers 2, 3, and 4 were old ships, not originally built for on board processing of the catch. Trawlers 1 and 5 were relatively new and built to accommodate processing machineries. On trawlers 1–4 round fish was produced; the head and entrails were removed before the fishes were frozen in blocks. Trawler 5 had the most extensive processing, producing fish fillets. Samples were analysed for total protein, trypsin activity, parvalbumin, and endotoxin. One side analysis of variance and Kruskal–Wallis H test were used to compare levels of exposure on the different trawlers. Results: Personal exposure to total protein were higher on the three oldest trawlers (2, 3, and 4) compared with the two new trawlers (1 and 5). Highest activity of trypsin was detected on the four trawlers producing round fish (1–4). Parvalbumin was detected in 58% of samples from the fillet-trawler (5) compared with 13% of samples from the four trawlers producing round fish. The highest level of endotoxin was detected when using high-pressure water during cleaning machines and floors in the processing area. Conclusions: Fishermen in the processing area on board Norwegian trawlers are exposed to airborne bioaerosols as proteins, trypsin, fish allergen parvalbumin, and endotoxin. Levels varied between trawlers and type of production

Exposure to Bioaerosols during Fish Processing on Board Norwegian Fishing Trawlers

Objectives: The main objective was to gain more knowledge on exposure to bioaerosols in the processing area on board fishing trawlers. Methods: Exposure sampling was carried out during the work shifts when processing fish in the processing area on board five deep-sea fishing trawlers (trawlers 1-5). Exposure samples were collected from 64 fishermen breathing zone and from stationary sampling stations on board five deep-sea fishing trawlers (1-5). Trawlers 2, 3, and 4 were old ships, not originally built for on board processing of the catch. Trawlers 1 and 5 were relatively new and built to accommodate processing machineries. On trawlers 1-4 round fish was produced; the head and entrails were removed before the fishes were frozen in blocks. Trawler 5 had the most extensive processing, producing fish fillets. Samples were analysed for total protein, trypsin activity, parvalbumin, and endotoxin. One side analysis of variance and Kruskal-Wallis H test were used to compare levels of exposure on the different trawlers. Results: Personal exposure to total protein were higher on the three oldest trawlers (2, 3, and 4) compared with the two new trawlers (1 and 5). Highest activity of trypsin was detected on the four trawlers producing round fish (1-4). Parvalbumin was detected in 58% of samples from the fillet-trawler (5) compared with 13% of samples from the four trawlers producing round fish. The highest level of endotoxin was detected when using high-pressure water during cleaning machines and floors in the processing area. Conclusions: Fishermen in the processing area on board Norwegian trawlers are exposed to airborne bioaerosols as proteins, trypsin, fish allergen parvalbumin, and endotoxin. Levels varied between trawlers and type of production

Exposures and Health Effects of Bioaerosols in Seafood Processing Workers - a Position Statement

Occupational hazards exist in the processing of seafood both in land-based facilities as well as on board vessels. Recent findings on occupational injury and respiratory health risks among seafood processing workers were presented and discussed at the IFISH5 conference. Particular emphasis was put on the challenges that im/migrant workers encounter, the greater risks onboard factory vessels, especially where processing machinery are retrofitted to older vessels not primarily designed for this purpose, and the difficulties in assessing and preventing bioaerosol exposures and associated respiratory health risks despite recent advances in characterising agents responsible for allergic and non-allergic reactions. Based on appraisal of existing knowledge in the published literature and new findings presented at the conference, recommendations for immediate actions as well as for future research have been proposed. Among these include the importance of improving extraction ventilation systems, optimising machinery performance, enclosure of bioaerosol sources, improved work organization, and making special efforts to identify and support the needs of im/migrant workers to ensure they also benefit from such improvements. There is a need for studies that incorporate longitudinal study designs, have improved exposure and diagnostic methods, and that address seafood processing in countries with high seafood processing activities such as Asia and those that involve im/migrant workers worldwide. The medical and scientific community has an important role to play in prevention but cannot do this in isolation and should cooperate closely with hygienists, engineers, and national and international agencies to obtain better health outcomes for workers in the seafood industry