What is Aerosol Loading?
Aerosols are defined as a ‘collection of airborne solid or liquid particles, with a typical size of between 0.01 and 10 micrometer (a millionth of a meter) that reside in the atmosphere for at least several hours.
Primary aerosols are the result of the direct injection of particles into the atmosphere, such as dust or sea spray, or originate directly from combustion sources, such as the soot from poorly maintained diesel engines.
Secondary aerosols, on the other hand, are the result of emission into the atmosphere of precursor pollutants (such as sulphur dioxide and ammonia) which underwhich undergo chemical reactions transforming them into aerosols after their release into the atmosphere. (Duvic-Paoli & Webster, 2021)
Why should we care?
Aerosols affect the Earth’s radiation budget. Depending on their characteristics and the conditions under which they occur, they reflect incoming solar radiation back into space. This has a cooling effect on Earth’s climate. But some particles can absorb radiation, which warms the air. Since they also serve as nuclei for condensation, aerosols also directly affect Earth’s water cycle. Water vapor can condense onto aerosol particles to form cloud droplets; this has a significant influence on the characteristics of clouds and the distribution of precipitation, and thus on our weather and climate.
In addition, increased air pollution also affects human health. For example, exposure to particulate aerosols smaller than 2.5 microns in diameter (PM 2.5) can cause cardiopulmonary disease and lead to increased mortality because such small particles can penetrate further into the respiratory tract. (Klima, 2025)
How does the fashion industry affects it?
The fashion industry contributes to 10% of global carbon emissions annually, more than the emissions from international flights and maritime shipping combined. The fashion industry’s aerosol loading comes primarily from manufacturing processes and, to a lesser extent, from the logistics chain—especially air freight as well as after care such as laundry fresheners that contain VOC (Volatile Organic Compounds)
The widespread use of synthetic fibers like polyester leads to the release of microfibers during washing, which can become airborne or enter waterways, indirectly contributing to aerosolized particulate matter and environmental pollution.
Although innovative aerosol technologies are being developed to reduce the environmental footprint of garment processing (Wahab & Hussain, 2020), the full impact of these new methods and the industry’s overall contribution to atmospheric aerosol loading requires further study and more comprehensive data.
700,00
How aerosol levels in the air are measured?
There are various ways to quantify the air’s aerosol content. One is to measure what is called the aerosol optical depth (AOD). We can draw conclusions about aerosol levels from the degree of atmospheric turbidity. Particles in the air weaken sunlight as it travels through the atmosphere. The higher the aerosol level, the greater the air turbidity and the higher the AOD.
An AOD of 0.25 has been specified as a boundary for limiting the negative impact on people and the environment to a level that is still marginally acceptable. This boundary should only be exceeded in exceptional situations. (Klima, 2025)
How can we minimize that effect?
The planetary boundary for air pollution by aerosols has not yet been completely quantified. However, it has become apparent that there are already high levels of aerosol pollution in the air in some regions. This makes it very important that we reduce emissions of aerosols that are hazardous to our health.
To reduce the fashion industry’s contribution to aerosol pollution, a comprehensive transformation across the supply chain is essential. This includes transitioning to renewable energy to power production, adopting cleaner processing technologies like waterless dyeing, choosing sustainable and circular materials, and improving waste and emissions management. These measures can significantly cut airborne pollutants by reducing reliance on fossil fuels, limiting hazardous chemical use, and capturing emissions before they reach the atmosphere.
Resources
Emetere, M., Emetere, J., & Osunlola, T. (2018). Dataset on aerosol loading, size and statistics over Sanpedro. Data in Brief, 20, 706–714. https://doi.org/10.1016/j.dib.2018.08.117
Müezzinoğlu, A. (1998). Air pollutant emission potentials of cotton textile manufacturing industry. Journal of Cleaner Production, 6(3–4), 339–347. https://doi.org/10.1016/s0959-6526(98)00013-4
Wahab, A., & Hussain, T. (2020). Eco-Friendly garment processing using aerosol technology. Water Resources and Industry, 23, 100127. https://doi.org/10.1016/j.wri.2020.100127
atmospheric aerosol loading. (n.d.). https://www.eionet.europa.eu/gemet/en/concept/15062
Duvic-Paoli, L., & Webster, E. (2021). Atmospheric aerosol loading. King’s College London. https://kclpure.kcl.ac.uk/portal/en/publications/atmospheric-aerosol-loading
Klima, H. (2025, March 13). Have we exceeded the planetary boundary for air pollution? Helmholtz CLIMATE. https://helmholtz-klima.de/en/planetary-boundaries-air-pollution-aerosols