Longitudinal dispersion of microplastics in aquatic flows using fluorometric techniques

Area of Science:

• Environmental Science
• Hydrology
• Chemical Engineering

Background:

• Microplastics are a growing environmental concern, but their movement in water is not well understood.
• Current models predicting microplastic transport lack sufficient real-world data for validation.

Purpose of the Study:

• To investigate the transport behavior of microplastics in water using a novel tracking method.
• To determine if fluorescent dyes can serve as reliable proxies for microplastic movement.

Main Methods:

• Utilized fluorometric principles to track fluorescently stained polyethylene microplastics and Rhodamine dye in laboratory flumes.
• Employed standard fiber-optic fluorometers for real-time movement monitoring.
• Simulated uniform open channel flow conditions.

Main Results:

• Neutrally buoyant microplastics exhibited transport behavior identical to that of Rhodamine dye, a solute.
• Microplastic and dye dispersion followed classical fundamental dispersion theory in uniform flow.
• Validated the use of fluorescent tracers for studying microplastic transport.

Conclusions:

• Fluorescent tracers like Rhodamine can accurately mimic microplastic movement in the water column.
• This method provides a viable approach for gathering empirical data to validate microplastic fate-transport models.
• Enhances understanding of microplastic dispersion in aquatic environments.