85 J. Indian Chem. Soc., Vol. 97, January 2020, pp. 85-100 Seasonal variation and health implications of long-range transported and provincial size distributed aerosols at eastern central India Mithlesh Mahilang and Manas Kanti Deb* School of Studies in Chemistry, Pt. Ravishankar Shukla University, Raipur-492 010, Chhattisgarh, India E- mail: debmanas@yahoo.com Manuscript received online 06 December 2019, accepted 26 December 2019 Size distributed aerosols are collected from October 2016 to July 2017 at eastern central India. This work for the first time investigates the possibilities of long-range transport and inhalation dose of particulate matters in different size at study site. During winter the aerosols were enriched in fine mode particles size however, they are more enriched in coarse mode during summer and post-monsoon season. Significant loading of particulate matters was observed during summer season. Crop resi- dues are burnt in large scale which increases fine particles in the atmosphere. Strong correlation between the fine size frac- tion were observed in summer and winter season which must be due to the strong biomass burning. The percentage loading of upper respiratory tract, respiratory tract and lungs were obtained to be 30, 69 and 52%, respectively during winter. High value of inhalation dose over entire study period which may responsible for severe health implications. Keywords: Size-distribution, inhalation dose, seasonal variation, biomass burning, eastern central India. Introduction Aerosols are suspended small liquid droplets and solid particles in air (except cloud particles) with size ranges from 10 –2 to 10 2 m 1,2 . Atmospheric aerosols have adverse ef- fect on human health and plays important role in atmospheric chemistry. They have some optical properties due to which they interact with incoming solar radiation and significantly affect Earth’s climate and participates as cloud condensa- tion nuclei (CCN), amending cloud formation and albedo. Particle size, shape, life time and chemical components are the properties that can be useful to predict the quality of air and the extent of pollution 3 . In recent years India has expe- rienced a significant raise in frequency of severe air pollu- tion. In contrast eastern central India has experienced an increase in Particulate Matters. Earlier studies reported that burning events like wildfire, Bourne fire, firecrackers burning and vehicular emission can inject fine and ultrafine particu- lates in atmosphere, and then these particles can be easily transported by air masses along the Earth because of their long-life time in atmosphere 4–6 . Aerosols have variety of chemical species they might be water-soluble inorganic ions, metals and organic compounds their compositions depend upon the sources from which they originated and atmospheric conditions 7–9 . Regardless of making significant efforts to con- Jan-6- p65 trol air pollution, these problems are growing as emerging issue regionally as well as globally. Recent study reported that approximately 800,000 people per year die due to air pollution hence air pollution control is one of the most rel- evant matter 10,11 . Size of the particles are the most important properties that decides the approach of the particles to different part of human respiratory system. Particles with size <10 m are the respirable suspended particulate matters (RSPM), which are more important because of associated health problems in human being. Particles with size 2.5–10 m (PM 2.5–10 ) and 2.5 (PM 2.5 ) m are the coarse and fine particles whereas particles with size < 1 m are ultrafine particles, smaller the particles have more harmful health effect because their ap- proach to the deeper respiratory regions 12,13 . Wang et al. (2019) stated that PM 4.4–10 can affect nasal and pharynx region whereas PM 1.0–4.4 and PM <1 can enters bronchi and alveoli regions of the lungs, hence more harmful to human health, also these are responsible for mortality, morbidity, asthma attack, exacerbation and cancer 14 . Most of the studies done represents aerosols effects in particular event or particular season, hence reflect aerosols transformation in short duration. Also, many studies have been done that only presents either PM 10 or PM 2.5 at a time.