Microplastics: tiny plastics, big problems

Microplastics – plastic particles smaller than 5 mm, are a pervasive contaminant that has been detected from the depths of oceans to the heights of Mt Everest, and even inside of our bodies. Microplastics are an emerging contaminant and researchers are just starting to uncover their effects on the environment and on human health. This means that there is a lot of potential for research, and Aotearoa New Zealand is a good setting for microplastic waterway research because it’s an island nation so there aren’t any messy geopolitical boundaries when trying to isolate point source pollution. New Zealand could be a leading example in microplastic freshwater research and while there are already several high-resolution analyses and studies, quantifying and establishing a baseline of microplastic concentrations around the country is a huge effort. This is where citizen science comes in.

Microplastics collected by students from our local river (Otepuni)

What is citizen science?

Citizen science, or participation of people in scientific processes who are not institutionally linked to that particular field of science, has been referred to as “the favoured twenty-first century model for conducting large-scale scientific research” (K. Toerpe, "The rise of citizen science," The Futurist, no. 4, 2013). Citizen science is an inclusive scientific methodology and there are innumerable social benefits ranging in scale of influence from increasing awareness in participants, to contributing to policies and national reports (e.g. the Sustainable Coastlines programme Litter Intelligence contributes to government reports about marine litter). Citizen science pushes the boundaries of research by expanding observation networks and databases in scope and availability to a larger extent or variety of spatial and temporal coverage. In the context of microplastics in waterways, citizen science could provide a nationwide snapshot of microplastic quantification, and help to identify hotspots that warrant further scientific investigation.

Micro-Investigators: microplastics citizen science

Since 2020, the Micro-Investigators programme has been implemented across schools in the Southland region in coordination with national organisation Enviroschools and various community groups. Primary school students use a plankton net to collect water samples from their local river and also try out various water quality sampling techniques (e.g. macroinvertebrate identification, clarity tube, water pH). Students from high schools are involved in the laboratory analysis and microplastics identification. Field and lab sessions are facilitated by tertiary students from the Southern Institute of Technology. Through this “Tuakana-Teina” framework the older students share their knowledge and set an example for the younger students, who can see first-hand some of the STEM pathways and further study in science that they could be getting into. At the end of the year we hold a Hui, or gathering, to celebrate the work of all the participants of the programme, and to give the students a chance to present their results and give a call to action to local council representatives and decision makers. The Hui consolidates learning and shows students that they have a voice and can make a difference.

Students from Makarewa School at a Micro-Investigators field session

Waterway microplastic concentration data

Besides the value added to education through hands-on environmental experiences, the data collected by citizen scientists is available and accessible on the Micro-Investigators website. The goal is to keep populating the microplastic concentrations map with more points on waterways, adapting long-term monitoring with the same schools returning regularly to their local river sites to measure microplastics and water quality. Ideally, after the first field session, the schools would be able to do the sampling themselves, since a good citizen science programme should ultimately be autonomous. In order to facilitate this autonomy, we put together sampling equipment and materials for 6 kits that have been placed in hubs around Southland. The kits include resources like how-to videos and manuals on how to use the equipment, in order to avoid sampling error, which is an important consideration for citizen science.

The microplastics data collected by citizen scientists is available on the Micro-Investigators website.

Success stories

We interviewed teachers whose classes were involved in the Micro-Investigators sessions and found that the programme fit well into their curriculum and that they wanted to see repeat sessions, which aligns well with our objective of ongoing environmental monitoring. One teacher told us about a student that arranged a meeting with the manager of their local supermarket to discuss alternatives to single use plastic packaging for produce. Students were sharing the ideas widely through media: a high school student even made a short documentary as part of the Keep New Zealand Beautiful Young Reporters Challenge, which won 1st prize in its category. The take home message of Micro-Investigators and one thing that makes it unique to conventional education, is that citizen science empowers the community and gives them the knowledge and resources to take environmental monitoring into their own hands.