A recent study by the University of Toronto shows that paints are a significant but previously overlooked source of microplastic pollution. Researchers are investigating how paint and varnish residues enter the environment and what measures can be taken to reduce the pollution.

Microplastics from paints are difficult to identify and have often been underestimated in the past.Source: University of Toronto

Plastic waste is one of the biggest environmental challenges we face. While bottles, bags and synthetic fibres are considered to be the main culprits, researchers at the University of Toronto have now identified an often-overlooked source: paints and coatings. In a recent study published in Environmental Toxicology & Chemistry, they analysed the extent to which paints contribute to microplastic pollution.

Although microplastic particles smaller than five millimetres have been detected in air, water and food, the influence of paints has so far remained largely unresearched. The scientists found that paint particles are often classified as ¡®anthropogenic unknowns¡¯ because their exact composition is difficult to determine.

Research deficit and first measures

A comparison with the existing literature clearly shows the research gap: while around 800 studies on microplastics were published in 2019, only 53 dealt with the influence of paints. On average, paints consist of 37% synthetic resins, which bind pigments and can serve as sources of microplastics.

To better understand the problem, researchers are working on a spectral library that can be used to identify paint particles more accurately. Initial measures to reduce paint pollution have already been tested, including special vacuum cleaner systems for construction sites that are designed to prevent paint particles from escaping into the environment.

Potential for sustainable alternatives

In addition to technical identification and better filter systems, the development of sustainable paint formulations is another solution. Bio-based or biodegradable binders could help to reduce environmental pollution.

The study shows that colour pollution is a widespread but previously underestimated problem. However, a reduction in microplastic pollution could be achieved through targeted research and innovative technologies.

Source: University of Toronto, 2025