Used in everything from water bottles to medical devices to building materials to clothes; plastic is a given in our daily lives. Yet, only about 9 per cent of plastic is recycled - the rest ends up as trash, polluting seas, oceans, landfills, soil and even the air we breathe.
The world generated 400 million tonnes of plastic waste last year alone. While many plastic products are not designed to be reused and recycled, others can only be recycled once or twice. Plastic is also not biodegradable. Instead of decomposing, discarded plastic materials break down into tiny particles - known as microplastics, which can be toxic to humans and the environment.
Enter an innovative solution: nuclear science. The IAEA is harnessing nuclear technology to both understand and tackle the plastic pollution crisis. The NUTEC Plastics initiative, launched in 2021, helps countries research microplastics already in the seas and uses nuclear techniques to improve recycling, ultimately reducing the flow of plastic waste into the oceans.
To mark World Environment Day, we spoke to Celina Horak, an IAEA expert on using radiation for plastic recycling.
Celina Horak speaking at a side event on NUTEC Plastics at the International Conference on Applications of Radiation Science and Technology (#ICARST2025), Vienna, 8 April 2025. (Photo: IAEA).
How can nuclear science help keep plastic waste out of the ocean and our daily lives?
Nuclear science offers innovative solutions to address plastic pollution across its entire lifecycle. To combat this challenge, we need to understand its root causes. Research indicates that approximately 80 per cent of marine plastic pollution originates on land (with the rest coming from ocean sources such as fishing nets etc.) making land-based interventions critical.
The IAEA is working on two fronts using cutting-edge technologies: firstly, we are using radiation to create bio-based plastics, offering a sustainable alternative to conventional petroleum-based plastics. Simply put, we are working on new materials that are both biodegradable and easily recyclable. This approach not only reduces reliance on fossil fuels but also supports circular economies by turning organic waste into valuable resources.
Secondly, we are using radiation technology to transform plastic waste into more durable, stronger and higher value products. For example, radiation can enhance the performance of concrete by partially replacing cement with recycled plastics. Nuclear techniques are improving the sorting and separation of polymers in mixed plastic waste streams. We're also exploring how radiation-assisted pyrolysis can convert plastics into waxes, fuels and other valuable chemical additives.
If we treat plastics using radiation, won't the new products be dangerous?
Not at all - in fact, quite the opposite. Radiation is considered a form of 'green chemistry' because it allows us to process materials without using toxic chemicals or extreme conditions like high temperature or pressure. When we use radiation to create new bio-based plastics or upcycle plastic waste, the process is clean, efficient and environmentally friendly.
And the radiation itself does not remain in the material. Just like when you get a dental X ray, the radiation passes through but doesn't stay with you. The same principle applies here: the materials are not radioactive after treatment and are completely safe to use.
You mentioned using nuclear technology to improve plastic recycling. Is this already happening?
Of the 52 countries collaborating with the IAEA under the NUTEC Plastics initiative for upcycling, nine have already established pilot plants - turning ideas into reality. These countries are advancing rapidly along the Technology Readiness Level (TRL) scale - a globally recognized nine-stage framework that tracks the maturity of technologies from concept to commercial deployment.
We're already seeing exciting, tangible results.
In Indonesia and the Philippines, wood-plastic composites are being developed for sustainable construction. In Malaysia, plastic waste is being converted into fuel. In Argentina, durable railroad sleepers made from recycled plastics are showing strong performance in early trials.
These pilot projects are not just proof of concept - they are proof of progress. We anticipate several of these technologies reaching the final TRL stages and moving toward full-scale implementation as early as next year.
Why, as a scientist, did you choose to go into this field?
I've always believed that science should serve as a catalyst for meaningful, lasting change. That belief led me to focus on plastic upcycling and the search for alternatives to petroleum-based materials - areas where innovation can directly address the environmental crises we face today.
With over 30 years of experience working with ionizing radiation, I've seen firsthand its untapped potential to transform waste into valuable resources. This work is more than research - it's a commitment to building a circular economy that safeguards our ecosystems, reduces human carbon footprint, and leaves a healthier, more resilient planet for future generations.
