Plastic Leak Urges Stronger Global Treaty

The Growing Threat of Micro- and Nanoplastic Pollution

Plastic waste is no longer just an environmental issue—it has become a pervasive threat to every corner of the Earth. From the deepest ocean trenches to the highest mountain peaks, plastic pollution is breaking down into microplastics and nanoplastics, which are now found in air, water, and soil. These tiny particles, often invisible to the naked eye, pose serious risks to human health and ecosystems worldwide.

A growing concern among scientists is the presence of nanoplastics, which are even smaller than microplastics and can penetrate biological membranes more easily. Their ability to enter the human body through food, water, and air makes them a critical focus for global environmental policies.

Scientists Push for Stronger International Action on Plastic Waste

Flinders University’s Associate Professor Melanie MacGregor, an ARC Future Fellow and Matthew Flinders Fellow in Chemistry, has been at the forefront of this issue. As part of the Scientists’ Coalition for an Effective Plastics Treaty, she has contributed to a scientific policy submission aimed at supporting the development of an international treaty to manage plastic production and waste. This submission was delivered ahead of the United Nations' final round negotiations, which will take place in August 2025.

The coalition emphasizes that plastics are not just a waste problem—they are a complex system with chemical components that can be released at every stage of their life cycle. This includes manufacturing, use, and disposal. According to MacGregor, “Nanoplastics are pollutants of concern to human health and ecosystems around the world,” and they must be addressed in any comprehensive plastic treaty.

The Scale of Global Plastic Consumption

The scale of plastic consumption is staggering. More than half of all plastics ever produced were made after the year 2000. If current trends continue, global plastic production is expected to double by 2050. Much of this plastic is single-use, and only a small fraction—less than 10%—is currently being recycled. This means that vast amounts of plastic are ending up in landfills, oceans, and natural environments, where they break down into micro- and nanoplastics over time.

MacGregor highlights the need for stronger controls on plastic industries, particularly regarding the release of chemicals and other harmful particles. She argues that measures must be taken to reduce emissions of greenhouse gases, volatile organic compounds, and other pollutants throughout the entire lifecycle of plastics.

Addressing the Root Causes of Plastic Pollution

Beyond regulation, there is a need for systemic changes in how plastics are produced, used, managed, and disposed of. One key area of focus is the intentional use of microplastics in various industries, such as cosmetics, paints, and textiles. These particles, which are less than 5mm in size, can eventually break down into even smaller nanoplastics, leading to further contamination.

MacGregor stresses that “millions of tons of microplastics can break down into even smaller nanoplastic particles and lead to chemical leakages.” This underscores the importance of addressing both the quantity and the quality of plastic waste.

Monitoring Plastic Pollution in Australia

Researchers at Flinders University have been actively monitoring microplastic levels in freshwater and marine environments in South Australia. A recent study found plastic pollution in seven water catchment areas that contribute to inflow into Adelaide and coastal regions. The most common types of microplastics found in freshwater samples were fibers (72%), followed by fragments (17%) and beads (8%).

These findings highlight the urgent need for better waste management practices and stronger policies to prevent plastic from entering natural water systems.

The Path Forward

The next session of the Intergovernmental Negotiating Committee (INC) will aim to develop an international legally binding instrument on plastic pollution, including its impact on the marine environment. This effort represents a critical step toward global cooperation in tackling one of the most pressing environmental challenges of our time.

As research continues to uncover the full extent of plastic pollution, it is clear that a coordinated, science-based approach is essential to protect both human health and the planet's ecosystems.