Research by: Eulle Stann Casaquite ’25 & Briana Reagan’25
Microplastics are very common pollutants that can be found in water systems and are defined as being the breakdown or larger pieces of plastic. They are measured as being less than 5 millimeters in size. They can be found in large oceans and even out local freshwater streams and they can harm our local ecosystems and environments, as previous studies have shown a negative trend in fish and stream invertebrates’ health in microplastic abundant streams. With there no denial of this being a rising issue in our local communities, we decided we wanted to study the abundance of microplastics in watersheds within the Quad Cities.
We learned that pinpointing the origins of microplastics poses another layer of complication. These broken-down plastics can enter a stream through direct dumping upstream, but they can also enter a stream through airborne means and animal transport. They can also flow from impervious surfaces in areas of heavy urban activity. This helped us decide to focus our study on sites that contained different land uses, including agricultural, urban, and natural. 17 sites were chosen to be sampled for this project, giving us a large gradient between these different land uses.
We directly collected our samples in various streams across the Quad Cities. Upon collection, the samples are then processed in a lab where it runs through several filtrations. Our end results leave us with a polycarbonate filter ready to be dyed. A special dye is directly added to the polycarbonate filter, this dye allows us to see the microplastics under a modified microscope. We then were able to count the number of plastics found in each sample, and compare each site with another. The initial goal of this project is to be able to quantify microplastics in these creeks. With our initial results from the samples, a relationship between specific attributes of land use and microplastic abundance is still being explored further.
This summer we both appreciated the importance of teamwork and time management. The processes that underwent our research required a lot of tedious work but were alleviated by splitting up work and collaborating with other groups. When processing our samples we developed a routine that played well into our strengths, which was essential to finishing our project in time.
This internship is a vital introduction for both of us to the world of research. We were given the opportunity to work in the field and the lab which gave us valuable experience that we will continue to use in the future. Being in the field allowed us to experience firsthand what it is like to walk through heavy vegetation in hot weather just to collect our samples. In the lab, we experienced making precise measurements while also making necessary changes when needed. Also, this internship was right after our first year at Augustana, so it was able to give us experience early on in our education. It helped us explore our field of study further, and give us a better understanding of work opportunities that are available after we graduate.
