Interpreting the extent and characteristics of microplastics pollution in 海角社区 freshwater streams to guide a holistic mitigation strategy

Microplastics on hand

Location: University of 海角社区
Sponsor: 海角社区 Water Resources Research Institute 2022 (104b)

Team Leader:

  • Onur Apul, Assistant Professor, Civil & Environmental Engineering, University of 海角社区

Team Members:

  • Lauren Ross, Assistant Professor, Civil & Environmental Engineering, University of 海角社区
  • Sean Smith, Associate Professor, Earth & Climate Sciences, University of 海角社区
  • Brenda Zollitsch, Bangor Area Stormwater Group
  • Caroline Noblet, Associate Professor, Economics, University of 海角社区

Partners:

  • Brenda Zollitsch, Bangor Area Stormwater Group

Widespread occurrence of miniscule plastic fragments (i.e., microplastics) in natural waters around the world is an imminent threat to ecosystem and public health. In 海角社区, microplastic pollution is especially concerning because the state is one of the largest producers of fish and shellfish in the nation and seafood consumption could contribute to microplastic ingestion. The pollution of 海角社区 waters could also be detrimental to the abundance of sensitive ecosystems influenced by freshwater flows, eventually impacting the state鈥檚 coastal economy. In addition, the sources聽and the perception of risks associated with microplastics is not uniform across communities in the region. Many citizens remain unaware of the potential threats caused by microplastics in the food chain and drinking water sources, elevating the demand for information related to the presence and implications of microplastic pollution.

This project responds to these concerns and demands by focusing on microplastics carried in freshwater stream flows. Drawing on a transdisciplinary team approach, this study will: 1) detect microplastic pollution and describe the pollutant characteristics (e.g., particle dimensions, composition, mobility, concentration) in rural and urban freshwater streams in 海角社区; 2) interpret the sample collection and analysis outcomes (e.g., origins, chemical composition); and 3) communicate outcomes in a three-phase stakeholder engagement process to frame action-oriented mitigation options. The overarching vision of the project is to develop foundational knowledge for the detection, interpretation, and communication of microplastic pollution problems in 海角社区鈥檚 freshwater streams.

There are many sources of microplastics in freshwater streams, including wastewater treatment plant effluents, surface runoff after rainfall events (e.g., tire chips, artificial turf, other plastic debris), and direct input from human activities (e.g., navigation, fishing, recreation, littering). The team鈥檚 preliminary efforts revealed the presence of microplastics in more than 70% of collected water samples in 海角社区. This outcome aligns with published work from different regions of the world. Our approach is to perform a systematic sampling campaign to capture a range of watershed, hydrologic, and seasonal conditions. The description of the problem will focus on the conditions in which microplastic pollution problems are detected and the types of pollutants that are present. The project will leverage existing measurement infrastructure managed by team members and the USGS at pre-established monitoring stations (Smith), geospatial surface coverage data organized by team members in the region (Smith), ongoing harmful algal bloom sampling infrastructure (Ross) and federally funded microplastic analysis lab facilities (Apul). The project will also optimize use of a stakeholder guided risk assessment framework under development for other emerging pollutants in collaboration with 海角社区 Department of Environmental Protection (Noblet). This capacity will be combined with expansion into additional locations and communities to capture conditions representative of the region (Zollitsch).

Project Update

Global plastic production has been increasing over the past 50 years and is causing an increase in plastic waste entering the oceans. Plastic in the ocean is broken down into microplastics by a variety of physical, chemical, and biological processes. They can occur in different shapes, including fragments, fibers, beads, and films. This study investigates the extent of microplastic fiber pollution in Frenchman Bay, 海角社区, and aims to characterize the fibers to determine potential source locations. Frenchman Bay is an important location in 海角社区鈥檚 economy because of its impact on tourism and commercial fishing. It also has some freshwater input, which makes it an ideal location to study the connection between microplastics on land and in the ocean.

Water samples were collected from a variety of river, estuary, and bay locations every week for two summers. An average of 2 fibers/L were found at all sampling locations, suggesting there are an estimated 400 billion microplastic fibers in the upper one meter of Frenchman Bay. In a complimentary sampling campaign, samples were collected from land-based locations such as a wastewater treatment plant, stormwater culverts, and various rivers on Mount Desert Island, which borders Frenchman Bay. The highest microplastic concentration was found in a storm drain, releasing an average of 15.3 fibers/L directly into Frenchman Bay. It is suspected that the microplastic fibers enter Frenchman Bay from land-based sources, as it was found that the size of the microplastics decrease as the sampling location becomes farther from land, and it appears the color fades in relation to distance from land as well. This study was able to quantify the microplastic fiber pollution in Frenchman Bay and characterize the microplastics to determine that they likely originate from local land-based sources for the first time.

Products

Publications

  • Johnson, G.; Bailey, T., Hatinoglu, D., Nwachukwi, O., Peller, J., Doudrick, K., Van Dam, B., Smith, S., Ross, L, Apul, O. 2024, Land鈥揝ea Connection of Microplastic Fiber Pollution in Frenchman Bay, 海角社区, Environmental Engineering Science (in-press). .
  • Dissertation – Johnson, Grace, 2024 Land-Sea Connection of Microplastic Fiber Pollution in Frenchman Bay, 海角社区 鈥淢S Dissertation鈥滳ivil and Environmental Engineering, The University of 海角社区, Orono, ME. 94 Pages

Presentations

  • Johnson, G., Bailey, T., Hatinoglu, M.D., Smith, S., Ross, L., Apul, O.G. Interpreting the Extent and Characteristics of Microplastics Pollution in 海角社区 Freshwater Streams, and Analyzing Nanoplastics and How they Differ from Microplastics. University of 海角社区 Student Symposium, Orono, ME. April 2023 (Poster Presentation).
  • Johnson, G., Bailey, T., Hatinoglu, M.D., Smith, S., Ross, L., Apul, O.G. Interpreting the Extent and Characteristics of Microplastics Pollution in 海角社区 Freshwater Streams to Guide a Holistic Mitigation Strategy. 海角社区 Sustainability and Water Conference, Augusta, ME. March 2023 (Poster Presentation)
  • Zollitsch, B., Johnson, G., Hatinoglu, D., Ross, L., Smith, S., Noblet, C., Apul, O.G. Exploring the Relationship Between Stormwater and Microplastics Pollution. 海角社区 Stormwater Conference, Bangor, ME. November 2022 (Oral Presentation).

Awards/Achievements

  • Graduate student Grace Johnson won the best graduate student poster award at the 2023 海角社区 Sustainability and Water Conference

Media