Reviewed by Lexie CornerOct 1 2024
Nasrin Alamdari, an assistant professor in the Department of Civil and Environmental Engineering at the FAMU-FSU College of Engineering, is determined to understand more about microplastics and their migration, as detailed in a study published in Environmental Pollution.
Nasrin Alamdari, assistant professor of Civil and Environmental Engineering at FAMU-FSU College of Engineering, poses by a stormwater culvert at Central Pond in Innovation Park in Tallahassee. Alamdari is studying the transport of microplastics from urban environments to water resources via stormwater runoff. Image Credit: Scott Holstein/FAMU-FSU College of Engineering
Microplastic pollution is a major environmental issue that impacts both wildlife and humans and disrupts ecosystems globally. Wind and water carry these tiny plastic fragments, less than five millimeters in size, across vast distances.
Nasrin Alamdari contributed to the study by examining how the shape, size, and density of microplastic particles affect their sinking rate, which in turn influences how stormwater disperses them.
Not all microplastics move through water in the same way. We need to know more about environmental degradation of microplastics and how they are transported in urban stormwater. This research helps us predict the paths different particles will take, which gives engineers a better understanding of how to capture this pollution.
Nasrin Alamdari, Assistant Professor, Department of Civil and Environmental Engineering, Florida State University
The researchers investigated how microplastics migrate from cities into our water systems when it rains. Using modeling, they studied how these particles move through cities and how their sinking or floating tendencies affect their pathways.
The study found that the shape of microplastics—whether fibers, sheets, or fragments—plays a significant role in their sinking rate, particularly as they increase in size. Smaller particles tend to float, while larger ones are more affected by their shape and water flow conditions.
More than 80 % of the plastic introduced into the marine environment comes from inland sources, resulting in a significant push to find long-term solutions to this growing problem. Hard surfaces in cities allow microplastics to be washed into rivers and lakes, harming organisms and potentially impacting human health.
“Urban areas, with their impervious surfaces, facilitate the rapid transportation of these microplastics into nearby water bodies, leading to contamination of aquatic ecosystems and potential risks to public health,” Alamdari added.
Urban stormwater runoff is polluted by microplastics from roads, highways, and residential, commercial, and industrial buildings. Tiny microplastics can also be transported by wind. Scientists can model how these microplastics move through the environment by examining the material's density, shape, and size. This modeling can inform strategies for incorporating infrastructure into traditional stormwater management systems to mitigate their spread.
Alamdari added, “Permeable pavements, rain gardens, and vegetated swales could be strategically deployed to reduce the transport of microplastics by enhancing filtration, trapping these particles before they reach storm drains. The slope of the land and the roughness of surfaces can affect how microplastics move. Knowing this, city planners can design better green spaces and stormwater systems to trap microplastics.”
Researchers from the Missouri Water Center, the University of Missouri, and Imam Khomeini International University in Iran co-authored the study. Arghavan Beheshtimaal from the University of Missouri is the lead author. The National Science Foundation funded the research.
Journal Reference:
Beheshtimaal, A., et. al. (2024) Understanding the dynamics of microplastics transport in urban stormwater runoff: Implications for pollution control and management. Environmental Pollution. doi.org/10.1016/j.envpol.2024.124302