Air pollution has a significant impact on human health, climate change, agriculture, visibility reduction, global warming, photochemistry, and ecosystem. About 7.0 million people die per year due to the outdoor air pollution, and 4.2 million people die per year for the indoor air pollution globally. Bangladesh became the topmost polluted country in the World for many years. Environmental pollution is the cause for 26% human death of the total in Bangladesh - two third of them are due to the worst air quality. Long term exposure of polluted air causes severe human health problem, e.g., chronic obstacle pulmonary disease, heart and brain stock, kidney and eye diseases, cancer, birth defect and affect the cognitive ability. The chemical composition of particulate matter (PM) is organic carbon (PAHs, VOCs, PFAS), black carbon/elemental carbon, brown carbon, water soluble ions (SO₄^2-, NO₃^-, Cl^-, PO₄^3-, Na⁺, K⁺, Ca²⁺, NH₄⁺, etc.), soil dusts (silicon dioxide, minerals), and trace elements (As, Cd, Cr, Ni, Hg, Fe, Zn, etc.). Fossil fuel combustion from industries, vehicles, constructions, biomass burning from indoor cooking, waste burning, dusts are significantly contributed to the worst air quality in Bangladesh. During winter transboundary air pollution from north and northwest has also been contributing to this poor air quality. The overview of the long-term trend of atmospheric PM (PM_2.5 and PM₁₀) and trace gases (SO₂, NO₂ and O₃, etc.) with PM chemical composition, source apportionment, health impact, heating rate, economic burden, and mitigation options will be presented in the conference.