Student-Built Low-Cost Filter Removes 96% of Microplastics from Water

Apr 10, 2026

Eighteen-year-old Mia Heller from Kettle Run High School in Warrenton, Virginia developed a low-cost ferrofluid-based filtration system that removes 95.52 percent of microplastics from water, surpassing traditional treatment plants that remove 70 to 90 percent. Heller created the flour-bag-sized prototype after government agencies refused to fund water filtering in her community despite high PFAS and microplastic contamination. The system uses magnetic oil to bind and extract microplastics from water while recycling 87.15 percent of the ferrofluid, offering a potential under-the-sink solution. Her innovation addresses a growing crisis as microplastic intake has increased sixfold since 1990 and brain tissue concentrations rose 50 percent in less than a decade, with contamination linked to cancers, cardiac disease, and Alzheimer's.

Mia Heller's ferrofluid-based filtration system development

▪Mia Heller was a finalist in the 2025 Regeneron International Science and Engineering Fair.
▪Mia Heller had a working prototype of her filtration system by early January 2025.
▪Mia Heller began working on her filtration system in the summer of 2025.
▪Mia Heller received a $500 award from the Patent and Trademark Office Society at the 2025 Regeneron International Science and Engineering Fair.
▪Mia Heller's current filtration system prototype is about the same size as a standard bag of flour.
▪Mia Heller's filtration system prototype consists of three modules.
▪Mia Heller attends a half-day program for math, science and technology at Mountain Vista Governor's School.
▪Mia Heller had the idea for her filtration system in the spring of 2024.
▪Mia Heller's filtration system harnesses ferrofluid, a magnetic oil that binds to microplastics in flowing water.
▪Mia Heller is an 18-year-old student at Kettle Run High School in Warrenton, Virginia.

Growing prevalence and health impacts of microplastics

▪A 2025 University of New Mexico study revealed that concentrations of microplastics in human brain tissue increased by 50 percent in less than a decade.
▪The Environmental Protection Agency defines microplastics as small particles measuring about 1 nanometer to 5 millimeters in size.
▪Microplastic intake by organisms has increased sixfold since 1990.
▪Microplastics have been found in 1,300 species, including humans.

System performance and scalability considerations

▪Traditional drinking-water treatment plants remove about 70 to more than 90 percent of microplastic components.
▪Mia Heller's filtration system prototype recycled 87.15 percent of the ferrofluid in testing.
▪Mia Heller's filtration system prototype removed 95.52 percent of microplastics from water in testing.

Perspective of Matthew J. Campen and public health researchers

▪The sixfold increase in microplastic intake since 1990 represents a significant escalation in environmental health threats.

Perspective of Traditional water treatment industry

▪Mia Heller's filtration system achieves higher microplastic removal rates than the 70 to 90 percent typical of traditional drinking-water treatment plants.