Scientific research on health risks of microplastics: Do plastics make us ill?
Published: 26 March 2019
Dick Vethaak of Deltares, who is involved in four of the fifteen research projects, explains: ‘Microplastics spread easily through water and the air, and that leads to a worldwide problem: they are everywhere in our environment like a sort of dull coating.
We are constantly exposed to small plastic particles through our food and drinks, or simply when we breathe. But it is still not easy to assess the implications for our health. There are strong indications of possible health risks but there are also many uncertainties and knowledge gaps.’ He continues: ‘So I’m very happy with this initiative from ZonMw and the involvement of the Plastic Soup Foundation. This is initial exploratory research that will bring together experts from a range of disciplines and sectors. The alliance of environmental scientists and medical specialists in particular is unique and powerful. The Netherlands is taking a global lead here. My expectations are high!’
At the Castel Laboratory in Utrecht, Deltares is identifying and weathering environmentally relevant plastics and supplying them to a number of projects. Deltares will also be studying the microbial biofilm that forms on plastics and that may be a source of disease and infection.
Biofilms on plastic and pathogens
Bas van der Zaan, water and health expert at Deltares, is working in one of the fifteen projects on an investigation of the health risks of microplastics that carry pathogens: ‘Micro-organisms like bacteria and fungi can grow on plastics that end up in the environment. It is very likely that these biofilms will also contain pathogenic bacteria. The structure of biofilms on microplastics is highly dependent on the environment where these microplastics are located. It is unclear which pathogens people are exposed to when they ingest microplastics through inhalation or ingestion, and whether this poses an additional risk to health.’
To find answers these questions, clean microplastics will be suspended in various environments (ditches, purified sewage water, etc.) so that a biofilm can form on them. DNA techniques will be used to determine whether pathogenic micro-organisms nestle in the biofilms. The immune response of these contaminated microplastics will be determined in a model with neutrophils (immune cells) to make it possible to assess the health risks for humans better. Deltares is working closely with the VU-University of Amsterdam, Utrecht University Medical Centre and the New York Military Academy (USA) on this study.
Just the start
ZonMw is emphasising that the grants for the fifteen projects are just the start. One year is not long enough to find all the answers. Henk Smid, the director of ZonMw, believes the studies have enormous potential and he therefore hopes that long-term follow-up research will be possible. ‘The Netherlands has a leading position worldwide in scientific research on microplastics and it should be expanded as quickly as possible.’