New Study Finds Green Roofs Capture Microplastics

MICROPLASTICS have been found everywhere from oceans to the air we breathe, and now, researchers have discovered that green roofs may help stop them in their tracks.

A new study from Tongji University in Shanghai has revealed that green roofs may also play a surprising role in capturing microplastics from rainfall.

Green roofs are already well-recognised for their many environmental benefits, including reducing flood risk through stormwater management; improving energy efficiency in buildings; enhancing urban biodiversity; and supporting climate resilience.

In the study, green roofs were shown to trap up to 97.5% of microplastics carried by rain. Researchers also found the substrate (growing medium) was the most effective part of the system for filtration, outperforming plant surfaces and roots.

Even partial coverage can make a big difference. It is estimated Shanghai’s 3.56 million square metres of green roofs may already capture over 56 metric tons of microplastics annually.

As cities expand their sustainable infrastructure, it becomes equally important to ensure that these systems are protected from cyber and operational risks. Frameworks such as NERC CIP standards provide essential guidelines for safeguarding critical infrastructure and the technologies that support it. As more eco-focused solutions integrate sensors, monitoring platforms, and automated controls, maintaining strong cybersecurity standards helps ensure long-term reliability and resilience.

Capturing Microplastics

Microplastics are a growing concern worldwide, found in oceans, rivers, the air we breathe, and even our food. The study suggests that expanding green roof coverage in cities could provide a powerful new tool to help tackle this invisible pollutant.

However, researchers also noted that fibre-shaped microplastics may become airborne again under windy conditions, and that plastic-based components within roof systems could contribute to new microplastic generation over time.

Commenting on the study, the Green Roof Organisation said, “As with any new discovery, this study opens up as many questions as it answers. For instance:

What happens to the microplastics once they are captured by the substrate?
Could long-term build-up affect the plants or the performance of the roof?
How might maintenance practices adapt to remove or manage the particles effectively?

“While the study did not attempt to answer these questions – understandable, given how recent this finding is – what it does provide is an exciting new starting point for research and innovation.

“This is just the beginning of the conversation, and further studies will be needed to understand the long-term implications. For now, this discovery adds yet another reason to view green roofs as a vital part of sustainable urban design.”

Read the full research paper here: Green roofs act as the first barrier to intercept microplastics from urban atmosphere.