Teen student creates water filter that removes 95.5% of microplastics
Microplastic pollution in drinking water has become a growing environmental and health worry, especially in the United States. In response, a student from Virginia, Mia Heller, has designed a new filtration system that could reduce microplastics in household water. At 18, Mia has designed an effective solution and won international recognition for her invention.
How she got started
Mia Heller’s work began at home in Virginia, where she and her family often had to replace and maintain their usual water filter. Their experience with membrane-based filters led her to seek a better, cheaper, lower-maintenance option. “That inspired me to design a filter without membranes in order to reduce the cost and maintenance burden of water filtration,” Mia told Smithsonian magazine.
She was also aware that state-funded filtration programmes lack sufficient support, leaving many people without easy access to proper filtration. She considered a household-level, easy-to-use solution more practical given that gap.
Building the first prototype
In 2025, Mia Heller built her first prototype in her parents’ garage. The system does not use membranes; it uses a magnetic fluid that binds microplastic particles. A magnet then removes those particles from the fluid, which can be reused, reducing the need for frequent filter replacements.
Roughly the size of a household appliance, the unit achieves a 95.5% removal efficiency, making it a candidate for domestic use. Prioritising reusability and lower running costs, the design may be cheaper and more convenient than typical household filters.
The magnetic-fluid approach is intended as an affordable market option. Its simplicity and focus on reuse make it suitable for households that want improved water quality without the ongoing expense of replacing standard filters.
Awards and what it could mean
Mia’s work drew attention quickly. In 2025, she was a finalist at the Regeneron International Science and Engineering Fair (ISEF). She received a special prize worth £390.00 (an equivalent of approximately £378.45) from the Patent and Trademark Office Society, a US organisation that supports innovation.
The filter’s performance also points to possible health benefits from reducing microplastic levels in drinking water. Research shows micro- and nanoplastics can cross biological barriers such as the blood–brain barrier, and may cause chronic inflammation, oxidative stress and impaired nerve-cell functioning. These effects can increase the risk of neurodegenerative conditions, including Alzheimer’s and Parkinson’s diseases.
Looking ahead
Mia Heller’s invention shows how young innovators can contribute to addressing environmental problems. The filtration system targets a public health concern while being designed to remain accessible and affordable for many households in the USA. Her project also highlights gaps in funding for state programmes and suggests a need for further investment in sustainable technologies.
As microplastic pollution remains a global issue, approaches such as Mia’s may be further developed to protect public health and the environment at lower cost and with high efficiency.