RESUMO
Thirty sediment samples from four different beaches along Bahia Solano and Nuquí (Department of Chocó) of eastern Colombia, with tourism and gold mining activities, were analysed to estimate the concentrations of fourteen different acid leachable metals. Metal distribution patterns showed elevated concentrations of Co, Cr, Cu, Pb and Zn compared with the upper continental crust values. Calculation of geochemical indices confirmed that the enrichment is due to periodic gold mining activities (severe to extremely severe enrichment of Cu, Zn, V, Co, Cr and Pb) along with natural (geological) contributions (minor and moderate enrichment of Ca, Mg, Fe, Ti, Mn and Li). Potential ecological risk index revealed that Pb posed the highest risk. Our results together with a global comparison suggest that the observed metal enrichments are mainly caused by mining and to a lesser extent by tourism in this region, thus instigating continuous monitoring of metal concentrations in this region.
Assuntos
Sedimentos Geológicos/análise , Metais Pesados/análise , Poluentes Químicos da Água/análise , Praias , Colômbia , Monitoramento Ambiental/métodos , MineraçãoRESUMO
A baseline study on metal concentrations in sediments was initiated from the Sodwana Bay and St. Lucia, adjacent to marine protected areas (MPAs) of South Africa. They were analysed to identify the acid leachable metal (ALM) (Fe, Mg, Mn, Cr, Cu, Mo, Ni, Co, Pb, Cd, Zn and Hg) concentration pattern. Metal distribution in 65 sediment samples exhibits higher abundances of Cr, Mo, Cd and Hg compared to the Upper Continental Crust. We relate the enrichment of these metals to beach placer deposits and activities related to former gold mining. Geochemical indices affirmed that Cr and Hg caused contamination, and Hg posed ~90% harmful effect on the biological community. These beach sediments, however, host lower metal concentrations compared to many worldwide beaches and other beaches in South Africa. This study suggests that it is largely unaffected by human activities, however, the overabundance of Hg demands regular monitoring.
Assuntos
Baías/química , Conservação dos Recursos Hídricos/métodos , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Metais Pesados/análise , Poluentes Químicos da Água/análise , Humanos , África do SulRESUMO
Brown tumours are highly vascular lytic bone lesions found in primary and secondary hyperparathyroidism. The brown term is given due to the red-brown colour of the tissue, which is due to the accumulation of hemosiderin. The case is presented of a 29 year-old male with chronic renal failure, who had a mass in the tip of the ring finger after a trauma of 4 months onset, which had increased progressively in size and pain. He was treated surgically, by amputation, with no recurrence 10 months after the surgery.