August 22 is National Fish Day. This day of action draws attention to the diversity of fish species, their habitats, and the challenges facing aquatic ecosystems today. After all, protecting fish begins not with individual animals, but with the condition of our rivers, lakes, and oceans.
Clean and, as far as possible, undisturbed waters are an essential foundation for functioning aquatic ecosystems. At the same time, these habitats are exposed to numerous pressures. In addition to rising water temperatures, changes in natural habitats, and various sources of pollution, one issue is increasingly coming into focus: microplastics.
Fish Day is therefore also an opportunity to take a closer look: How do microplastics end up in our waters, what impact do they have on aquatic habitats, and what options are there for removing these tiny plastic particles from waterways?
Microplastics are defined as plastic particles smaller than five millimeters. They are manufactured at this size for various purposes (e.g., decorative glitter) or are produced by the breakdown of larger plastic products. Through various pathways, the particles enter the environment and eventually end up in rivers, lakes, and oceans.
There, they become part of a complex ecosystem. Microplastics have already been detected in various aquatic organisms and can also be ingested by fish. The potential long-term consequences for individual species and entire ecosystems are the subject of intensive research.
A particular challenge lies in the fact that microplastics are not a homogeneous substance. The particles differ in size, shape, chemical composition, and origin. This makes both their reliable detection and their assessment and removal challenging.
This day of Fishes thus also serves as a reminder to take a holistic approach to water protection. Anyone who wants to protect fish and other aquatic organisms must also address the quality of their habitats and the substances that enter these habitats.
From Water Bodies to Humans
Microplastics have long been more than just an issue for aquatic ecosystems. The particles can also enter the human food chain via water, air, soil, food, and various processing methods.
A study published by the WWF in 2019 and conducted by the University of Newcastle in Australia attracted significant attention. Based on the data available at the time, it was estimated that, depending on their consumption habits, people could ingest up to five grams of microplastics per week—roughly the weight of a credit card. However, the actual amount ingested remains subject to considerable uncertainty and is the focus of ongoing research.
A key challenge lies in the analytical process. Variations in particle size, plastic types, and testing methods make it difficult to reliably determine and compare microplastics. Standardized and reproducible measurement methods are therefore essential for better assessing exposure levels.
This is precisely where solutions from i3 Membrane come into play: specially developed membranes support sample preparation and can facilitate the subsequent detection and characterization of microplastic particles.
How can microplastics be removed from water?
In addition to preventing new inputs, another crucial question arises: How can existing microplastic particles be reliably removed from water streams?
Modern filtration processes play an important role here. Depending on particle size and application, membrane technologies can help separate even very small particles from water streams. At i3 Membrane, we focus on membrane solutions for demanding filtration tasks and on the targeted functionalization of membrane surfaces. In doing so, we aim to make a technological contribution to efficient separation processes and the responsible management of water as a resource.
Focus on Microplastics: Continued in November 2026
The issues surrounding microplastics extend far beyond Fish Day. Science, industry, analytics, and regulatory bodies are intensively exploring how microplastics can be reliably detected, assessed, and removed from various material streams.
In November 2026, we therefore invite you to our second in-house event, “Focus on Microplastics,” right in the heart of Hamburg.
Experts from across the DACH region will shed light on current developments and issues. Topics will include standardization and harmonization, reference materials, the latest findings on potential health risks posed by microplastics, microplastics in the food industry, and the analysis and removal of microplastics from wastewater.
Registration for “Focus on Microplastics” is now open. Further details about the event will follow shortly.
Would you like to test our membranes for microplastic analysis with no obligation? Order our free sample pack here.