Chemical composition of the street dust of Guwahati with special reference to speciation of the heavy metals

Abstract

Title: Chemical composition of the Street Dust of Guwahati with special reference to speciation of the heavy metals. This thesis describes and discusses the results of evaluating the environmental status of the street dust of Guwahati city along the major thoroughfares with the following specific objectives: (i) Physico-chemical characterization of the street dust samples with respect to pH, EC, Texture Cation Exchange Capacity Exchangeable cations Na, K, Ca, Mg Total concentrations of Al, As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sn, V and Zn. (ii) Chemical speciation study of the heavy metals in the street dust. (iii) Analysis of road run-off to evaluate the ecotoxic potential (iv) Estimation of metal uptake by roadside plants, and (v) Heavy metals associated with suspended particulate matter (SPM) The thesis is organized into six chapters, viz., (1) Introduction, (2) Literature Review, (3) Study area and experimental methodology, (4) Results and discussion (5) Conclusions (6) References. Chapter 1 (Introduction) starts with a general description of the environmental pollution and its effects, heavy metal pollution, roadside pollution, heavy metal contamination of street dust and roadside soil, road runoff, roadside plant materials and suspended particulate matter. The importance of the studies of the contamination levels of the street dust particularly by heavy metals is reviewed at national and international levels. The different environmental parameters that influence urban environment have been brought into focus with reference to relevant literature. Chapter 2 (Literature Review) gives a brief description of available literature which are having direct or indirect relevance to the topic of research. The areas covered include a general description of the environmental importance of the heavy metals, their occurrence in nature, how they behave in nature, different uses of the heavy metals and the subsequent release to the environment, anthropogenic sources, etc. have been discussed on the basis of the existing...