[Geospatial models for local health surveillance]. / Modelos geo-espaciales para la vigilancia local de la salud.

OBJECTIVES: To produce a geospatial model to evaluate lead exposure among school children from 6-8 years of age, in San Antonio Oeste, Rio Negro province, Argentina, an area contaminated by a foundry in the city center whose toxins were released into the open air. METHODS: The spatial analysis conducted from October-April 2006 included satellite interpretation and mapping of the data to geographically plot the information. Residences on dirt roads were included, as was the distance for each of the study children's homes and/or schools to the site identified as the source of the exposure. RESULTS: Blood samples taken from children attending schools within the area surrounding the source showed higher lead levels than that of children in other areas. These lead levels were associated with the proximity to the source and/or with living on a dirt road. The highest blood lead levels corresponded to the higher environmental lead levels. CONCLUSIONS: Spatial analysis was shown to be a useful tool for site analysis and risk management since it indicated a definitive association between elevated lead levels and the proximity to the source, and/or residing on a dirt road, connections which had not been revealed with traditional epidemiological analyses. The results provided the scientific evidence needed to begin implementing interventions regarding the sources of exposure and education aimed at promoting more hygienic dietary habits among the population.

Modelos geo-espaciales para la vigilancia local de la salud / Geospatial models for local health surveillance

OBJETIVOS: Generar un modelo geo-espacial para evaluar la exposición a plomo de escolares de 6 a 8 años, residentes de San Antonio Oeste, en la provincia de Río Negro, Argentina, localidad contaminada por una fundición en el casco de la ciudad y la acumulación a cielo abierto de sus residuos. MÉTODOS: El análisis espacial llevado a cabo de octubre a abril de 2006 incluyó la interpretación satelital y el georreferenciamiento de los datos para la espacialización de la información. Se tomó en cuenta la localización de las residencias sobre calles de tierra y la proximidad, desde el domicilio y/o la escuela de los niños bajo estudio, a los sitios-fuente como puntos de exposición. RESULTADOS: Las muestras de sangre tomadas a los niños en las escuelas en el área de influencia de alguna fuente, mostraron mayor abundancia de plombemias elevadas que las localizadas en otras áreas. Dichas plombemias se asociaron con la cercanía a alguna fuente y/o la ubicación de las residencias sobre calles de tierra. Los valores más altos de plomo en sangre correspondieron a mayores rangos de plomo ambiental. CONCLUSIONES: El análisis espacial constituyó una metodología complementaria útil para el análisis y la gestión de riesgo del sitio contaminado, al indicar una asociación positiva entre plombemias elevadas y la proximidad a la fuente, y/o el hecho de vivir en calles de tierra, que no se había hecho evidente mediante los análisis epidemiológicos tradicionales. Los resultados aportaron la evidencia científica necesaria para indicar la implementación de medidas de intervención directas sobre las fuentes de exposición y de educación, orientadas a fomentar hábitos dietéticos higiénicos en la población.

OBJECTIVES: To produce a geospatial model to evaluate lead exposure among school children from 6-8 years of age, in San Antonio Oeste, Rio Negro province, Argentina, an area contaminated by a foundry in the city center whose toxins were released into the open air. METHODS: The spatial analysis conducted from October-April 2006 included satellite interpretation and mapping of the data to geographically plot the information. Residences on dirt roads were included, as was the distance for each of the study children’s homes and/or schools to the site identified as the source of the exposure. RESULTS: Blood samples taken from children attending schools within the area surrounding the source showed higher lead levels than that of children in other areas. These lead levels were associated with the proximity to the source and/or with living on a dirt road. The highest blood lead levels corresponded to the higher environmental lead levels. CONCLUSIONS: Spatial analysis was shown to be a useful tool for site analysis and risk management since it indicated a definitive association between elevated lead levels and the proximity to the source, and/or residing on a dirt road, connections which had not been revealed with traditional epidemiological analyses. The results provided the scientific evidence needed to begin implementing interventions regarding the sources of exposure and education aimed at promoting more hygienic dietary habits among the population.