Epidemic asthma in Barcelona: an evaluation of new strategies for the control of soybean dust emission.
BACKGROUND
Asthma attacks and mortality due to inhalation of soybean antigens in Barcelona have been well documented. Strict protective measures in the unloading process were established in 1998 to avoid the release of soybean dust into the atmosphere. The present study was undertaken to assess the effectiveness of these latest environmental measures, and, if effective, to recommend their implementation in the many harbours where soybean is unloaded.


METHODS
Levels of soybean aeroallergen were analysed daily during a period of 5 years and 2 months in a total of 1,854 samples, 125 from the pre-intervention period and 1,729 from the postintervention period. Additionally, the number of asthma admissions to the emergency rooms of the city's three largest hospitals was recorded. Asthma patients attended at home by the public home emergency service and judicial autopsies registering asthma deaths were also investigated.


RESULTS
The mean concentration of soybean aeroallergen was 159 U/m(3) in the pre-intervention period and 39 U/m(3) in the postintervention period (p < 0.0001). Significant differences in postintervention aeroallergen concentrations were found between days of soybean unloading (42 U/m(3)) and days of no unloading (33 U/m(3)), with p < 0.0001. No significant relationship was found between concentrations of environmental soybean aeroallergens and the number of emergency room admissions for asthma.


CONCLUSIONS
Implementation of stricter protective measures in silos for the soybean unloading process has reduced the concentration of soybean dust in the atmosphere and evidences the effectiveness of the measures adopted.
Rodrigo
María-José
MJ
Unitat de Recerca en Neumologia i Unitat Immunologia, Servei de Pneumologia, Hospital Universitario Vall d'Hebrón, Universidal Autónoma de Barcelona, Passeig Vall d'Hebrón 119-129, ES-08035 Barcelona, Spain. mjrodrigo@vhebron.net
Cruz
María-Jesús
MJ
García
María-del-Mar
MD
Antó
Josep-María
JM
Genover
Teresa
T
Morell
Ferran
F
D000393:Air Pollutants / Q000009:adverse effects / Q000032:analysis; D000485:Allergens / Q000009:adverse effects / Q000032:analysis; D000918:Antibody Specificity / Q000276:immunology; D001249:Asthma / Q000453:epidemiology* / Q000209:etiology / Q000517:prevention & control; D004196:Disease Outbreaks; D004391:Dust / Q000032:analysis / Q000517:prevention & control; D004632:Emergency Medical Services; D006801:Humans; D007114:Immunization; D007073:Immunoglobulin E / Q000276:immunology; D010343:Patient Admission; D011446:Prospective Studies; D012720:Severity of Illness Index; D013025:Glycine max / Q000737:chemistry; D013030:Spain / Q000453:epidemiology
D000393:Air Pollutants; D000485:Allergens; D004391:Dust; D007073:Immunoglobulin E