Trace metal

About: Trace metal is a research topic. Over the lifetime, 5125 publications have been published within this topic receiving 181046 citations.

The Distribution of trace metals and fauna in the firth of clyde in relation to the Disposal of Sewage Sludge

Abstract: Trace metals have been determined in the sediments, waters and fauna of a sewagesludge disposal area in the Firth of Clyde. Enhanced values of organic carbon and several metals were found in the sediments of the immediate deposit area. The results are discussed in relation to local background variations and compared with data from the Solway Firth. Trace-metal concentrations in the waters of the deposit area were higher than those from further off shore in the Clyde.Epifaunal species showed rather erratic variation in trace metal content, unrelated to total or readily extractable trace metals in the underlying sediment. The tracemetal content of demersal fish species was not significantly different from figures reported for elsewhere in the United Kingdom.The distributions of some in-faunal and epifaunal species in the area are described.It is concluded that the effects of sewage sludge disposal in this area are local, gross changes being limited to an area of about 20 km2 of sea-bed. However, little is known of the overall effects of toxic wastes particularly at threshold levels, and further monitoring is required.

Physiological and toxicological changes in the skin resulting from the action and interaction of metal ions

Abstract: The human environment contains more than 50 metal or metalloid elements. At least 15 are recognized as trace elements, with zinc, calcium, copper, magnesium, and iron having specific roles in skin morphogenesis and function. The present review focuses on the presumed role of metal ions in the skin, their competition for carrier proteins, and membrane receptors. Evidence presented shows that the balance of trace metal ions is critical for normal skin and repair mechanisms following injury. Xenobiotic ions can impair this balance, leading to pathological change. The skin acts as an organ of elimination of excess trace metals and xenobiotic ions from the body, but mechanisms of voidance vary for different metals.Metal ions are an important cause of allergies, and evidence is presented to show that the majority of metals or metal compounds can induce allergic changes. Except for chromium and nickel, which are among the most common human allergens, animal models have provided little information.At leas...

Assessment of Trace Metal Contamination in Water and Sediment of Some Rivers in Bangladesh

Abstract: Trace metal contamination is a major problem globally, especially in developing countries. In this study, the levels of trace metals (Cr, Ni, Cu, As, Cd, and Pb) in water and sediment of some peripheral rivers of Dhaka City, Bangladesh, were investigated. Huge amount of municipal wastes, industrial effluents and agricultural runoff from the periphery of Dhaka City notably are dumped to these rivers. Most of the effluents channeled into these rivers are not treated. Sediment and water samples were collected from selected stations along the various rivers in winter and summer seasons and analyzed for the trace metals of concern. Considering the sampling sites, the decreasing order of total metal concentration in water samples were Cr > Cu > As > Ni > Pb > Cd and in sediment were Cr > Pb > Ni > Cu > As > Cd. Total concentrations of Cr, As and Pb in the water samples were higher than WHO guidelines for drinking water quality for some sites. Geoaccumulation index (Igeo) revealed high values of Cd for all the stations. The extent of metal pollution in the rivers around Dhaka City implied that the condition is much frightening and probably severely affecting the aquatic ecology of the rivers.