A new study by researchers from AMBER, the SFI Centre for Advanced Materials and Bioengineering Research, Trinity, and University College Dublin shows that tap water creates a natural protective shield against harmful microplastics.
This phenomenon can help prevent the release of harmful microplastics from household products like plastic kettles.
The study has been published in the Chemical Engineering Journal and shows that tap water includes trace elements and minerals that prevent the degradation of plastics in the water and the release of microplastics. Microplastics can carry a wide array of contaminants like trace metals and certain potentially harmful organic chemicals.
Earlier research works analyzing the release of microplastics have used forms of pure water, which only occur in laboratories and do not particularly consider the impurities and ions found in tap water.
It is well known that plastics can degrade and release microplastics, which can get into the environment and be consumed by humans. Our research shows that many items such as plastic kettles, which are repeatedly used with tap water, can develop over time a protective skin that prevents the release of microplastics entirely.
John J Boland, Research Team Co-Leader and Professor, AMBER and School of Chemistry, Trinity College Dublin
“Because tap water is not 100% pure H2O — since it contains trace elements and minerals, what we showed is that if you include these trace elements and minerals the degradation of plastics in tap water is completely different,” added Professor Boland.
Rather than the plastics falling apart, the minerals coat the plastic and prevent any kind of degradation and so the product becomes microplastic-free. For example, that dark brown colour in your kettle is a good thing. It is copper oxide that forms from copper minerals in your tap water, which in turn comes from the copper pipes in your house—all these combine to give a perfect protection to the kettle.
John J Boland, Research Team Co-Leader and Professor, AMBER and School of Chemistry, Trinity College Dublin
“This discovery is important because we have learned that these types of protective skins can be manufactured in the laboratory and directly applied to the plastic without having to wait for it to build up naturally. This discovery also shows that nature is leading the way, pointing to solutions to what is a very significant problem facing our modern high-tech society,” Professor Boland concluded.
The team of researchers was headed by Professor Boland and Dr. Jing Wang, from AMBER, CRANN and Trinity’s School of Chemistry, along with Professor Liwen Xiao from Trinity Haus and Trinity’s School of Engineering.
The researchers were supported by Enterprise Ireland, Science Foundation Ireland, the School of Engineering Scholarship at Trinity, the China Scholarship Council and the Irish Research Council.
Journal Reference:
Shi, Y., et al. (2022) Real-world natural passivation phenomena can limit microplastic generation in water. Chemical Engineering Journal. doi.org/10.1016/j.cej.2021.132466.