Researchers at the University of Reading have come closer to understanding why fatty acids, emitted in significant quantities by fast food outlets cooking meat, persist for so long in the atmosphere.
Christian Pfrang and colleagues, studied the ozone oxidation kinetics of methyl oleate monolayers at the air–water interface using experiments designed to mimic the atmospheric degradation of aerosols formed from fatty acid surfactants and moisture droplets. The experiments were carried out by skimming a fine beam of neutrons off a free air–water interface while the oxidation reaction took place. They found that the methyl ester monolayers broke down much faster than expected based on reported lifetimes in the atmosphere, suggesting that the long-chain organics are taken up into the droplet itself, where they are protected from further ozonolysis.
The presence of particulate matter in the atmosphere is a major health concern and may ultimately have significant climate change implications. Reports suggest that around a third of directly emitted aerosols above central London come from cooking, the majority of which are rich in oleic acid derivatives produced by cooking meat. These types of emissions are on the rise as vehicles move towards biofuels, another source of fatty acid methyl esters.
Interested to know more?
Read the article in PCCP:
Ozonolysis of methyl oleate monolayers at the air–water interface: oxidation kinetics, reaction products and atmospheric implications
Christian Pfrang, Federica Sebastiani, Claire O. M. Lucas, Martin D. King, Ioan D. Hoare, Debby Chang and Richard A. Campbell
Phys. Chem. Chem. Phys., 2014, Advance Article