There are already more than 500 filters analyzed in the BiSC campaign!
As you know, part of the environmental visit to the participants was to carry a backpack with various equipment for two days to measure their personal exposure to air pollution. One such device is a pump that passes air through a filter. This filter collects particles less than 2.5 µm called PM2.5 that are suspended in the air we breathe.
How are filters analyzed in the laboratory?
Once the filters arrive in the laboratory the filters are digested. This technique involves attacking the filter with different acids in order to release the particulate matter (PM) from the filter and dissolve it to obtain an acid solution without any solid components in it.
Where is the solution analyzed?
Once the acid solution is obtained, it is analyzed using the mass spectrometry (ICP-MS) and optical (ICP-AES) technique with inductive coupling plasma, where the solution is nebulized and converted into an aerosol. This aerosol is then ionized and the ions are conducted to the mass spectrometer where they are separated according to their mass. This system allows a multi-elemental analysis of the sample in a quantitative way.
The text has been written by Quim Cortés, a researcher of the BiSC project.