May 4, 2026

expert reaction to study on airborne microplastics and nanoplastics and global warming

A study published in Nature Climate Change looks at global warming contributions from airborne microplastics. 

Dr Ria Devereux, Environmental Research Fellow, University of East London, said:

“Microplastics and nanoplastics originate from the fragmentation of larger plastic waste and range in size from 1 nanometre (one billionth of a metre) to up to 500 micrometres (one millionth of a metre) in diameter.”

“This sentence is misleading the size ranges, if combining nano and microplastics, should then be from 1 nanometer to 5 millimeter (mm) (1nm – 5mm). Whilst 500 micrometers is within the microplastic range it is not the upper limit as it does not equal 5mm it only makes 0.5 mm. Which is the not the scientific size standard that is widely accepted when referring to micro and nano plastics. I could not find anything in the study regarding the size range that was used so i assume that they were working on the scientifically accepted size range.

“The paper itself is very interesting especially with regards to the possible impacts the colour of the micro and nanoplastics on warming potential. However this is still a computer model combined with limited lab experiments, and not a direct real world measurement.

“Therefore, it has limitations in real world applicability. The laboratory conditions used were simpler than in the real world as plastics break down in more complex interconnected ways not just from UV, but from humidity, chemicals, wave action to name a few. The model also assumes global distributions of plastic colours and distribution. Another limitation that has not been accounted for is particles that have 2 or more visible colours as well as their shape (i.e. fibre, particle).

“micro- and nanoplastics suspended in the atmosphere may contribute to global warming at a level equivalent to 16.2% of that caused by black carbon”

With regards to the statement above this does not mean plastics are causing 16.2% extra global warming. It means they are possibly releasing a small but measurable amount of direct radiative forcing (DRF) which is 16.2% of what black carbon emits. Micro and nano plastic combined release roughly 0.04 W m-2 compared to Black Carbon 0.13-0.37 W m-2 (this study used 0.27 W m-2).

“What I find more interesting is that certain areas like the gyres and coastal regions had higher levels and that the DRF varied between micro and nano plastics. If future research shows similar results it may mean that coastal region and areas of high pollution may need further and more specific regulation when it comes to air pollution including the monitoring of atmospheric micro and nanoplastics.”

Dr Sam Harrison, Environmental Modeller, UK Centre for Ecology & Hydrology (UKCEH), said:

“There is growing evidence that plastic pollution can exacerbate the impact of many planetary boundaries, including climate change, ocean acidification, altered biogeochemical flows and biosphere integrity. We know that plastic pollution causes microplastic and nanoplastic particles to be transported in our atmosphere, however there is still a lot of uncertainty around the distribution of these particles in the atmosphere and their impacts on atmospheric warming. This new publication offers supporting evidence that plastic particles present in the atmosphere can absorb light and so may lead to increased atmospheric warming, though we need more evidence before we can confidently conclude the impacts of plastics on climate change.”

Dr Eiko Nemitz, an environmental physicist at the UK Centre for Ecology & Hydrology (UKCEH), said:

“The paper highlights the interesting potential of micro- and nanoplastics exerting a warming effect in the atmosphere. However, the uncertainties of this effect are substantial, not only due to the variability of their optical properties, but also due to our limited understanding of their emissions and a lack of measurements to assess model predictions. This means that we need further research before we can confidently discuss the magnitude of the impact of micro- and nanoplastics on atmospheric warming.

“If substantiated by further work, micro- and nanoplastics should then be considered short-lived climate forcers like black carbon itself. This means their contribution to global warming could be reduced much more quickly through emission reductions than is the case for changes in emissions of carbon dioxide and nitrous oxide, for example, which persist in the atmosphere for many, many years. Nevertheless, the benefit would be fast but limited and should not distract from the need to control emissions of the primary greenhouse gases.

Dr Jim Walker, Research Fellow in Aerosol Science at the University of Bristol, said:

“In this study, the researchers used laboratory measurements of the optical properties of microplastic particles (MPs) to estimate their potential impact on the global climate. Their findings suggest that this previously overlooked factor could contribute towards warming, though to a much lower extent than greenhouse gas emissions, with MP colour – rather than plastic type – emerging as an important factor.

“It is important to acknowledge the substantial uncertainties associated with these estimates, as is the case for aerosol impacts more broadly. However, these uncertainties underscore the importance of continued research in this area to better understand how human activities are influencing the Earth’s climate system.”

‘Atmospheric warming contributions from airborne microplastics and nanoplastics’ by Yu Liu et al. was published in Nature Climate Change at 16:00 UK time on Monday 4 May 2026. 

DOI: 10.1038/s41558-026-02620-1

Declared interests

Dr Ria Devereux: No interests to declare. 

Dr Eiko Nemitz: No interests to declare.

Dr Sam Harrison: I have received funding from industry, including the European Chemical Industry Council (Cefic) and BASF.

For all other experts, no response to our request for DOIs was received.