Fish-inspired filter promises to curb microplastics from washing machines

German researchers have developed a washing-machine filter that traps more than 99% of microplastics in laundry wastewater, a breakthrough that could significantly cut household microplastic emissions. In a four-person household, a single unit can produce up to 500 grams of microplastics per year as synthetic fabrics shed fibers, according to the study notes and researchers involved. Microplastics are fragments that break off from larger plastic items and are found in air, water, soil and food; the smallest particles can pass through many filtration systems and may eventually enter human tissues.

The team’s filter design draws inspiration from the way certain fish feed by filtering water through their gill arches. The gill-arch system features a funnel-shaped passage with comb-like structures and tiny teeth that trap plankton while letting water flow through. Dr. Alexander Blanke, one of the study’s lead researchers, said the team used that natural architecture as a model for a practical washing-machine filter. “We took a closer look at the construction of this system and used it as the model for developing a filter that can be used in washing machines,” Blanke explained in a press release. “During food intake, the water flows through the permeable funnel wall, is filtered, and the particle-free water is then released back into the environment via the gills.” In the fish, larger particles are caught by the sieve and rolled toward the gullet, where they are cleared as the fish swallows. The researchers adapted that concept to a compact, detergent-compatible filter that sits in washing-machine wastewater streams.

The researchers note that the funnel-shaped design helps prevent clogging while achieving high filtration efficiency. Lead author Dr. Leandra Hamann said, “The filter systems available so far, however, have various disadvantages. Some of them quickly become clogged, others do not offer adequate filtration.” By adjusting both the sieve mesh size and the funnel angle, the team says they found a combination that can remove more than 99% of microplastics from the water without blocking. The filter traps the plastics and allows the cleaned water to pass on. The captured microplastics collect in the filter and are suctioned away several times a minute; the material can be pressed to extract remaining water, forming a dry pellet that can be removed every few dozen washes and discarded with regular trash.

Importantly, the researchers say the concept does not require elaborate, heavy machinery, making it inexpensive to manufacture. The team has applied for a German patent and hopes manufacturers will integrate the filter into future washing machines. If adopted broadly, the technology could curb the spread of microplastics from textiles, a concern that has grown as evidence mounts that these particles may pose health risks.

Microplastics are known to enter the human body through ingestion, inhalation and skin contact. They have been detected in human placentas, kidneys, lungs, livers, testes and blood, among other organs and tissues. While long-term effects require further study, research to date suggests they can damage intestinal cells, trigger inflammation and disrupt gut bacteria balance, with potential implications for reproductive, digestive and respiratory health and possibly increasing the risk of certain diseases.

The urgency to curb microplastics is mirrored by mounting calls for practical solutions in consumer electronics and home appliances. The German team’s approach emphasizes a low-cost, scalable filter that can be added to existing systems or integrated into new washing machines. Even as the science on health effects evolves, the notion of stopping microplastics at the source—before they enter wastewater—has gained traction among environmental researchers and policymakers.

The researchers’ patent application signals a pathway toward commercialization, and industry observers say the concept could prompt a wave of similar innovations across household devices that shed microfibers. As washing machines remain a primary source of microplastics in daily life, the fish-inspired approach offers a concrete example of translating natural filtration strategies into practical engineering solutions.

Several images accompany related coverage of this topic.

Researchers testing a fish-inspired filter in a lab setting illustrate the level of investigation researchers are pursuing to refine the mechanism before market introduction. The study’s researchers emphasize that the design’s simplicity makes it feasible to scale, potentially enabling broad adoption if manufacturers integrate such filters into new models as standard or optional equipment.

In summary, the German research team asserts that a gill-arch-inspired microplastic filter could dramatically reduce household emissions from laundry waste, delivering a practical, low-cost option that aligns with broader climate and environmental goals. As scientists continue to quantify health risks and refine performance, the pathway to commercialization remains under active development.