VTT Finland investigates waterway microplastic prevention through nanocellulose structures

24 Apr 2020 --- Finland-based research facility VTT is developing a method that uses nanocellulose structures for the early identification of microplastic particles before they enter waterways. Microplastics are just 100 nanometers in diameter – the width of a human hair. Moreover, the nanocellulose structures may prove instrumental in determining the concentration of microplastics in water as well as in analyzing how many particles are released into drinking water from plastic bottles.

“We are only at the beginning of the work showing that nanocellulose hydrogels and films can collect even the smallest colloidal fraction of microplastic particles in a size range lower than one micrometer. The potential is high since it seems that the capturing performance is relatively efficient. Currently, we see that solution could help best as on-site filters where such plastic particles are formed, such as in laundry,” Tekla Tammelin, Research Professor at VTT, tells PackagingInsights.

Microplastic particles are often released from fleece clothing and other synthetic fibers in laundry. Similarly, the VTT research team aims to develop filtration methods for any industry where there is a risk of microplastics being generated and released into waterways. Packaging is widely recognized as one of the major contributors to microplastic pollution.

A scanning electron microscope shows how the microplastic particles are attached to the nanocellulose structure. The diameter of the plastic particles is 100 nanometers. Currently, the research team has produced nanocellulose hydrogels and films on a pilot-scale level. However, microplastic recovery and quantification tests have yet to be carried out at lab scale.

“In this case, we are dealing with water treatment concepts. In the short term, we could bring solutions [to address] the lack of current detection methods that are needed for quantification and qualification of microplastic particles. There is a blind spot for the recovery of smaller colloidal sized particles and therefore very little is known about their abundance in the environment,” says Tammelin.

However, the question of what risks the nanocellulose structures themselves pose to the environment must be “carefully considered” as the research project continues. “Generally speaking, nanocellulose is a fully renewable natural material, but any of the material solutions should not be considered as disposable without a clear plan on recycling and waste treatment after the end of life,” Tammelin highlights.

Concerns about human and environmental microplastic contamination recently culminated when microplastics were found in rainwater samples from the rural Rocky Mountain National Park last August. This indicated that the pollution of plastic fibers is not just an urban condition and that they are everywhere – in our air, water and soil.

A recent study found that up to 75,000 microplastics can be flung across three meters when different types of plastics packaging are opened. In August, the World Health Organization’s assessment of microplastics in the environment indicated that the impact on human health appears to be minimal at current levels. At the same time, WHO has stressed that it was working from “limited information” and that there is a pressing need to establish more standardized methods for measuring microplastic particles in water; more studies on the sources and occurrence of microplastics in freshwater; and the efficacy of different treatment processes.

By Anni Schleicher