Microplastic Pollution is No Small Problem in our Headwaters

Watershed Co-op Zack Smith collecting a microplastic sample in Crum Creek at Kirkwood Preserve. Photo by Monica McQuail/Staff. Watershed Protection Co-op Zack Smith holding a microplastic sample taken at Rushton Woods Preserve. Photo by Lauren McGrath/Staff.

By Zack Smith, Watershed Protection Co-Op

Mass production and consumption of plastic have reached all corners of our globe, from the depths of the oceans to the air around us, and even right here in Willistown. Plastic pollution comes in all shapes and sizes, but microplastics have been receiving increased attention due to the way they infiltrate our natural spaces. Specifically, microplastics are pieces of plastic that are less than 5 millimeters in diameter. Plastics at this size are called primary microplastics. Secondary microplastics occur when litter or other plastic refuse enter the environment and begin breaking into thousands of little pieces. Consequently, scientists have been finding plastics in almost every single spot they look for them — including in our own bodies.

Microplastic pollution has been documented in museum collections of fish specimens dating back to the 1950s, which indicates that microplastics have likely been a danger to life on Earth since their invention. Plastics carry contaminants and pathogens that can harm species by hindering their ability to properly function. Oceans, the atmosphere, and urban rivers have been the main focus of most microplastic research, but very little has been done to document microplastic pollution in low order streams.

Here at the Trust, we want to ensure the land and waters we preserve are facing as few impacts as possible by understanding all pressures and pollutants as best we can. With microplastics being documented across global landscapes, we couldn’t help but wonder: are microplastics present in the headwaters of Ridley, Crum, and Darby Creek?

The Trust initiated the study of microplastic pollution during the summer of 2020 when Watershed Protection Program Co-Op Zack Smith of Drexel University analyzed the Trust’s “historic” water samples that had been gathered from January of 2018 through March of 2020. After discovering the presence of microplastic pollution in these samples, Smith eliminated the potential for cross-contamination by adjusting sample protocol to include plastic-free sampling.

Using glass sampling jars and plastic-free processing, in April 2021, Willistown Conservation Trust Co-Ops Gloria Avila, Chase Foster, Niya Moss, Zack Smith and Anna Willig and Director of the Watershed Protection Program Lauren

A microplastic sample being transferred from a vacuum filter onto a tin tray where it will then be dried and inspected for plastic pollution. Photo by Lauren McGrath/Staff. A microplastic grab sample after it has been filtered. This filter will then be inspected for any microplastic contamination under a microscope. Photo by Lauren McGrath/Staff.

McGrath collected and analyzed 76 samples gathered from the Ridley, Crum, and Darby Creeks within the Trust’s 28,000acre focus area. Of these samples, 100% contained the presence of microplastic pollution.

The hope is that this method will show truer values of the microplastics in our waterways and help us determine ways we may be able to further understand this pollutant. Currently, we believe that waste water is where much of the plastics come from in our area. Our goal is to constantly monitor the health of our waterways so we can relieve any unwanted strain on our downstream neighbors. For years, microplastics have been regarded as a downstream problem due in part to their large quantities in terminal locations like oceans. Our work is showing that this is not the case. In fact, microplastic pollution is a global problem and a local problem, one that is impacting all areas of life.

Our goal is that protections and regulations, such as land protection and monitoring, can be put in place to help reduce the amount of plastic entering our waterways. Conserving land reduces the number of impervious surfaces — surfaces that do not allow for water to absorb into the soil — and can help reduce runoff during storm events, which slows the rate of plastic entering water bodies. Riparian buffers along streams help to slow runoff and reduce the inflow of pollutants by filtering them out. Having these critical spaces in sensitive headwater regions can go a long way in helping to provide healthy and usable water for our downstream neighbors. Reducing the amount of plastics introduced into our environment is also necessary to alleviate the stress on our waterways for good.

Reducing the impact of microplastics will take a lot of work, but the Watershed Protection Team has already taken steps to begin doing so. With this study, we can clearly see that microplastic pollution is an issue that exists in the headwaters of our watersheds, and we must work to further raise awareness of this issue and continue to monitor the persistent problem of microplastic pollution. At home, some of the easiest ways to reduce your plastic footprint are to choose plastic alternatives, add microplastic filters to your washing machines, and to make sure that all items are getting used to their maximum potential. If we can decrease the plastic leaving our homes, local water treatment plants will discharge less into our local waters. Visit www.wctrust.org/plastic-free-july-resources/ to learn more about how we can work to reduce microplastic pollution.