Paper Title
Physical Characterization of Settled Indoor/Outdoor Dust Particles using Scanning Electron Microscope (SEM)

Abstract
In recent years, Harmattan, a dusty weather condition characterized by thick smog-like suspended particles and dust storm are the peculiar events that happen during ¾ of the year in the Sahelian regions including Damaturu Town, Nigeria, resulting into heavy dust deposits especially indoors. These weather events with the increased in temperatures are considered to be the result of climate change. The inhabitants of the Damaturu community are always inflicted with different ailments; respiratory tract infections, asthma, gastrointestinal infections and different ailments associated with the dusty nature of the immediate environment. This brought the need to investigate the nature of the settled indoor as well as outdoor dusts. Vacuum cleaner bag dusts were collected from indoor of some Nigerian and UK homes, and outdoors during the seasonal dusty weather events (Harmattan and Storm), and also when there was no weather event. The dusts were sieved and the (150 µm size) particles were examined using scanning electron microscope (SEM). The physical characterization of the settled dust samples has revealed the various shapes and sizes, and elemental composition of the dust samples indicating that some of the dust fractions were the respirable fractions and also the dust contained PM10 to PM2.5 fractions with possible health effects. The elemental compositions were indicative of the diverse nature of the dust particle sources, which showed dust as a complex matrix. Keywords - Harmattan dust, SEM, Storm dust, Indoor/Outdoor