Additional source of ultrafine dust identified

Hessenschau, 9/01/2023

It has been known for years that air traffic at Frankfurt Airport produces large quantities of harmful ultrafine dust. Researchers have now proven that these are not only caused by the combustion of kerosene, but also by lubricating oils.

Researchers at Frankfurt’s Goethe University have demonstrated that ultra-fine dust particles are produced when synthetic lubricating oils are used in aircraft turbines. The Hessian State Agency for Nature Conservation, Environment and Geology (HLNUG) and the Goethe University provided information on this.

Measurements and laboratory experiments have shown that these arise as soon as the very hot exhaust gases from the turbines cool down.

Genesis traced in the laboratory

“Our investigations suggest that these particles make up a large part of the ultrafine dust produced by aircraft turbines,” explained Alexander Vogel from the Institute for Atmosphere and Environment at Goethe University.

Last year, when examining ultrafine dust particles, his team came across a group of organic compounds whose chemical composition can be traced back to synthetic lubricating oils. Further measurements have now confirmed this. In addition, it was possible to reproduce the formation of the particles in laboratory experiments.

The previous assumption that the ultrafine dust is mainly produced when kerosene is burned is apparently not correct. This must be taken into account when taking measures to reduce fine dust pollution. “According to our knowledge, a reduction in lubricating oil emissions has important potential for reducing ultrafine particles.”

Study aims to clarify airport pollution

Ultrafine dust is produced during combustion processes. In addition to road traffic, large airports are an important source. Due to their small size of less than one hundred millionth of a millimeter, they can penetrate deep into the lower respiratory tract, cross the blood-air barrier and, depending on their composition, cause inflammation in the tissue, for example. They are also suspected of being able to trigger cardiovascular diseases.

The HLNUG has been measuring the number and size of ultrafine particles at various air measurement stations, also in the immediate vicinity of the airport, for several years. In a scientific study by the state of Hesse on particle pollution planned for this year, airport-specific particles are to be identified, among other things, in order to develop targeted counter-strategies.