Particles, Particles Everywhere: What Is in the Air We Breathe? Kathleen Purvis-Roberts [view bio] June 20, 2017 Particulate matter (PM) air pollution consists of extremely small particles, some so small that they can pass directly from the lungs into the bloodstream. PM is of prime concern from both health and environmental perspectives. Current research is focused on understanding how PM forms in the atmosphere from various pollution sources and how to better control it. This talk focuses on two sources of PM: agricultural and nuclear testing. Agriculture is a primary source of air pollution in many areas, including California's Central Valley and the Salt Lake City area. Amine gases are emitted into the atmosphere from animal husbandry operations, but the mechanism for how these gases react in the atmosphere to form particles is poorly understood. Field studies were done on a dairy in the central valley of California and a poultry farm in Bowling Green, KY, followed by more theoretical studies in an environmental chamber. This has enabled a better understanding of how the PM forms from agricultural emissions and provides insights for controlling their formation. Radioactive particles form during the detonation of nuclear weapons and can present potential exposure pathways to people living nearby. Radioactive particles can be picked up in the wind and form a particularly dangerous form of PM air pollution. A field study was done on the Semipalatinsk Nuclear Test Site in Kazakhstan, where above ground nuclear tests were done, to understand potential human exposure from blowing dust.