Environmental Distribution of Trace Metals in the Biu Volcanic Province Nigeria: Exposure and Associated Human Health Problems Lar, U.A, Usman, A. M
Abstract: This study focuses on the concentration levels of trace metals in the soil and natural waters of Biu Volcanic Province Nigeria as well as human health problems associated with the exposure to these elements. Advance Inductively Coupled Plasma Optical Emission Spectrometry was used to analyze the trace and major elements. The analysis of the soil samples revealed complete leaching of the potentially harmful elements (As, Se, Sb, and Pb) from the surface soils into the water sources. According to pollution index the Soils are contaminated with Cr, Mn, Co, Ni, Zn and Lead, while water is contaminated with As, Pb, Sb and Se. The long term exposure of these toxic elements through the ingestion of water and food could have adverse health hazard to the inhabitants. Index Terms—: Volcanic Province, potentially harmful elements, health hazard
The Biu volcanic covers a superficial area of 5000Km2 with a thickness of 250m, made up of several simple volcanoes with very large craters (caldera) of greater than 1km, suggesting that quite a large volume of magma, volcanic ash and pyroclastic materials erupted. Volcanism and related igneous activities redistribute harmful elements, (such as arsenic, beryllium, cadmium, mercury, lead, radon, and uranium) on the surface of the earth. Through physical and chemical weathering processes, rocks break down to form the soils on which the crops that constitute the food supply are raised for humans and animals consumption. Drinking water travels through rocks and soils as part of the hydrological cycle and in the process leached elements in solution . Environmental pollution arising from the distribution elements by natural or anthropogenic processes distorts geochemical systems. The natural geochemical composition of rocks and soils that make up the environment where we live may become direct risks to human health and may be the underlying cause of element deficiency and toxicity . The purpose of this study is to determine the concentrations levels of trace metals in the soil and natural waters of Biu Volcanic Province Nigeria as well as human health problems associated with the exposure to these elements. ————————————————
2 GEOLOGICAL SETTINGS
Biu Plateau is situated on the structural and topographic divide, a broad E-W ridge or swell of basement between the Benue and Chad sedimentary basins “Fig. 1”.
U. A. Lar, Department of Geology and Mining, University of Jos, Nigeria. +2348037039175. Ualexanderlar@yahoo.co.uk U.A. Mohammed, National Steel Raw Materials Exploration Agency, (Bauchi Exploration Base), Bauchi, Nigeria. :firstname.lastname@example.org
Fig. 1: Location Map of Biu Plateau and other Rock types in Nigeria (After Wright, 1976)
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International Journal of Scientific & Engineering Research, Volume 3, Issue 10, October-2012 ISSN 2229-5518
The basalt of the Biu Plateau mainly overlies Basement rocks which are predominantly granites, granitegneiss and Fayalite-quartz, Monzonite, Bauchites (near Wandali at the SW margin of the plateau), hypersthenes diorite, volcanic and sub volcanic rocks of the Burashika group . Two important post depositional processes affect the Poliocene basalts. The first was internal, the crystallization of zeolites and calcite, which are abundant in vesicular and rubbly interflow horizons. The second is surface weathering to clays and laterites. The basalt of the poorly drained northeastern plains is deeply decomposed to clay presumably a continuing process. Much less widespread, but...