A thesis submitted to the University of Mumbai for the Ph.D. (Science) degree in Physics
under the guidance of Prof. Nathani Basavaiah.
Brief of Conclusion : Environmental pollution due to anthropogenic sources of vehicular exhausts and industrial emissions is rapidly becoming a critical issue of public concern worldwide. Industrialization, urbanization, population growth and associated increase in energy demands have resulted in a profound deterioration of environmental quality in urban India. Specifically, burning of fossil fuels in industries and transport sector has led to increase in
concentrations of particulate pollutants in the environment leading to pollution, which can threaten the health of human beings and affect the quality of environment. The increasing pollution level day-by-day has prompted policy makers, scientists, environmental organizations to opt for fast, cost effective, complimentary yet reliable tools against the existing traditional time consuming, cost intensive and destructive tools for quick
information. Environmental magnetism is one such tool which has been widely used to investigate the degree, source, scope and spatio-temporal evolution of anthropogenic pollution related to industrial and other human activities in this thesis. The determination of different magnetic mineral sources, called magnetic components, is an important task in environmental magnetism. The premise is based on that human activities constitute an additional source of magnetic components, which can be utilized for pollution monitoring. Technical challenges in recognition of anthropogenically produced magnetic particles in high magnetic background values from Deccan Trap basalts pose difficulties in order to define accurately a standard magnetic reference level. For the first time, two case studies of a successful pollution screening from Deccan Trap basalts employing integrated
environmental magnetic, geochemical and microscopic investigations were carried out. Further, in situ susceptibility survey and laboratory measurements of a suite of rock magnetic parameters were carried out for obtaining information on spatial magnetic dust/soil, carrying a load of environmentally relevant heavy metals.
Mineral magnetic measurements as a tool for mapping heavy metal contamination of road dusts and topsoils around a power plant were reported here. As aforementioned, virtually all types of magnetic matter generated by anthropogenic mechanisms outlined were within coarser particle range from 0.2 m up to tens of m. Thus for representative particulate nature of the road dusts and contaminated topsoils and for minimization of natural magnetic contamination of the basaltic environment, the dust samples <44 µm and topsoil samples <63
µm fraction were analyzed in detail. This fractionation process ensured removal of coarse grains of basaltic material and contained a large component of the anthropogenic dust particulates of airborne origin. We briefly summarize the results and provide a brief of the future scope of the present thesis work.