RESUMEN
The village of Furnas, like other active volcanic areas in the world, exhibits high levels of hazardous gases. We aimed to investigate the existence of a possible association between chronic exposure to volcanic sulfur gases and chronic bronchitis. To investigate this, we used two populations, one exposed to active manifestations of volcanism (Furnas) and another from an area where no volcanic activity took place for over three million years (Santa Maria), both in the Azores. We used data on the incidence of chronic bronchitis among both populations (1991-2001), obtained from the records of each local health center, and population denominators from censuses carried out in 1991 and 2001, using five age-groups. We also estimated relative risks and mean annual age-standardized rates of chronic bronchitis incidence. Incidence rates were extremely higher in the volcanically active area for both sexes, and especially in the youngest groups. Accordingly, the risk of chronic bronchitis for the people living in the volcanically active area was extremely higher (males RR=3.99; females RR=10.74) when compared to those living in the volcanically inactive area. Comparison of chronic bronchitis incidence rates between both populations suggests an association between this disease and the chronic exposure to the volcanically active environment, with all its hazardous gases like hydrogen sulfide and sulfur dioxide. These findings may help health officials to better advice people inhabiting volcanic areas, or others with high levels of sulfur gases, on how to prevent and minimize the risks of chronic bronchitis.
Asunto(s)
Contaminantes Atmosféricos/análisis , Bronquitis Crónica/epidemiología , Exposición a Riesgos Ambientales/estadística & datos numéricos , Erupciones Volcánicas , Adolescente , Adulto , Factores de Edad , Anciano , Bronquitis Crónica/etiología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Portugal/epidemiología , Factores de Riesgo , Factores SexualesRESUMEN
The chloragogenous tissue and the intestinal epithelium of adult earthworms, Lumbricus terrestris, sampled from sites with and without volcanic activity in the Azores were submitted to hematoxylin/eosin staining, autometallography and TUNEL-test in order to quantify the radial thickness of both tissues, their relative abundance of metals and apoptosis levels. Metals were visualized, through light microscopy, as black silver deposits (BSD) mostly in the chloragogenous tissue. The lowest radial thickness values of both tissues were found in the active volcanic sites, as well as the highest BSD and apoptosis levels. The BSD extent in the chloragogenous tissue, semi-quantified by stereology, exhibited a positive correlation with the apoptosis levels and a negative one with the radial thickness of both tissues. Thus, the variation of the radial thickness of both tissues, but especially of the chloragogenous tissue, which could reflect different cellular turnover rates caused by exposure to metals, is suggested as a biomarker of effect for metal exposure in terrestrial worms inhabiting volcanic environments.
Asunto(s)
Apoptosis , Tracto Gastrointestinal/citología , Tracto Gastrointestinal/metabolismo , Metales/metabolismo , Oligoquetos/citología , Oligoquetos/metabolismo , Animales , Biomarcadores/metabolismo , Núcleo Celular/metabolismo , Epitelio/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/citologíaRESUMEN
The digestive gland of adult land snails, Helix aspersa, sampled from four different sites in São Miguel island (Azores) was submitted to chemical analyses, autometallography and haemalum/eosin staining, in order to quantify the relative abundance of heavy metals, calcium cells and connective tissue cells. Metals were visualized, through light microscopy, as black silver deposits mostly in the connective tissue cells. Metal levels, essentially of Cu and Fe, were related to the relative volumetric density of connective tissue cells but not to the relative volumetric density of calcium cells from the digestive gland epithelium. Thus, the connective tissue index presented herein is suggested as a biomarker of Cu exposure in terrestrial mollusks.