Brake wear emissions - a hidden source of volatile organic compounds and secondary particles

The aim of this project is to determine the importance of brake wear as a source of volatile organic compounds and secondary organic aerosol in ambient air.We recently discovered that volatile organic compounds from brake wear emissions can lead to the formation of secondary organic aerosols. This is an unknown phenomenon that no one has studied before.

The knowledge gained in this project can be used to, for the first time, evaluate how the gases emitted from brake wear contribute to the burden of gaseous and particulate air pollutants.Road traffic is one of the main sources of urban air pollution.

Unlike exhaust emissions, non-exhaust emissions from road traffic, such as brake wear, are still unregulated and therefore now often exceed exhaust emissions.

While particles directly emitted from the braking process have already been studied in detail, only little is known about the gaseous emissions and their fate in the atmosphere.We will use state-of the art mass spectrometry to identify and quantify volatile organic compounds emitted from the braking process in a controlled laboratory setting.

As a second step, we will determine the secondary organic aerosol formation potential of these emissions through photooxidative aging in an oxidation flow reactor.

Finally, we will establish how the toxicity of the emissions changes upon aging using an in-vitro model of the human lung.