Recent discoveries regarding aerosols from cooking emissions and sea spray indicate that these particles may absorb more moisture than earlier models suggested, which could impact how long they persist in the atmosphere.
Research conducted by the University of Birmingham has found that pollutants creating nanostructures are capable of absorbing significantly more water than simpler models have indicated. When these particles absorb water, they become heavier and eventually fall to the ground as rain, reducing their presence in the atmosphere.
The research team, which included scientists from the University of Bath, utilized facilities at Diamond Light Source to investigate the water absorption properties of oleic acid, a substance commonly found in cooking emissions and sea spray. They employed a method known as Small-Angle X-ray Scattering (SAXS) to explore how the internal structure of the particles relates to their water absorption and chemical reactivity.
Operating at Diamond’s I22 beamline and collaborating with the I22 team and specialists from the Central Laser Facility at the Rutherford Appleton Laboratory, the researchers examined how humidity fluctuations altered the structures of the pollutant particles. They demonstrated that when these molecules react with ozone in the atmosphere and break down, they can reform into various 3-D structures that have different capacities for water absorption and reactivity with other chemicals.
The results, published in Atmospheric Chemistry and Physics, indicate that these interplay effects allow oleic acid particles to remain airborne for extended periods.
Lead researcher Professor Christian Pfrang stated, “As we enhance our understanding of the behavior of these particles in the atmosphere, we can create more advanced strategies for managing air pollution.” He added, “For instance, safeguarding harmful emissions from degrading in the atmosphere could enable them to travel further, significantly expanding the reach of pollutants.”
He also emphasized, “Our findings reveal that aerosols are in a dynamic state, characterized by the formation and destruction of complex structures. Each of these states enables pollutants to remain in the atmosphere for longer durations. To reduce exposure to cooking-related pollutants, individuals should utilize extractor fans and ensure good kitchen ventilation to facilitate the quick dispersal of aerosol particles.”
