0
Article ? AI-assigned paper type based on the abstract. Classification may not be perfect — flag errors using the feedback button. Tier 2 ? Original research — experimental, observational, or case-control study. Direct primary evidence. Sign in to save

Settling Velocities of Tire and Road Wear Particles: Analyzing Finely Graded Density Fractions of Samples from a Road Simulator and a Highway Tunnel.

Environmental science & technology 2025 Score: 38 ? 0–100 AI score estimating relevance to the microplastics field. Papers below 30 are filtered from public browse.
Stefan Dittmar, Steffen Weyrauch, Thorsten Reemtsma, Paul Eisentraut, Korinna Altmann, Aki Sebastian Ruhl, Martin Jekel

Summary

Researchers measured the terminal settling velocities of tyre and road wear particles (TRWP) from a road simulator and highway tunnel across different density and size fractions, providing the first empirical settling velocity data for these particles to support modeling of their transport in aquatic environments.

The terminal settling velocity is considered the most critical parameter determining the transport of tire and road wear particles (TRWP) in aquatic environments. Nonetheless, no respective empirical data has been reported so far. In this study, particle samples from a road simulator and a highway tunnel were investigated with a validated imaging method. Different density and size fractions of both samples were measured separately, acquiring sizes and settling velocities of more than 30,000 individual particles. In addition, tire marker polymers were analyzed for each fraction via thermal extraction desorption-gas chromatography/mass spectrometry. Finally, the acquired particle data was combined according to the fractions' estimated tire contents in order to deduce detailed probability distributions of particle size and settling velocity for the actual TRWP from both samples. Weighted by TRWP-incorporated tire mass, median diameters of 54 and 44 μm as well as median settling velocities of 0.65 and 0.22 mm/s were found for TRWP from the road simulator and highway tunnel, respectively. This study thus provides the first ever empirical data on TRWP settling velocities in water, which can be highly valuable input for modeling the environmental transport of TRWP and for dimensioning TRWP retention systems.

Sign in to start a discussion.

More Papers Like This

Article Tier 2

The transport of tyre wear particles in rivers, with a focus on settling and resuspension

Researchers investigated the transport dynamics of tyre and road wear particles (TRWPs) in river systems, with particular focus on settling and resuspension processes in aquatic environments, and explored pathways toward groundwater, addressing a gap in understanding TRWP fate in the environment.

Article Tier 2

The transport of tyre wear particles in rivers, with a focus on settling and resuspension

Researchers investigated the transport, settling, and resuspension behavior of tyre and road wear particles (TRWPs) in river systems compared to conventional microplastics, presenting initial characterization data on TRWP density and zeta potential and conducting mesocosm flume experiments to test hypotheses about their differential environmental fate.

Article Tier 2

Analysis of TRWP Particle Distribution in Urban and Suburban Landscapes, Connecting Real Road Measurements with Particle Distribution Simulation

Researchers combined road-based tyre and road wear particle emission sampling with particle distribution simulations at a high-traffic urban intersection, finding that TRWP concentrations correlated with vehicle dynamics such as braking and acceleration, and that air humidity and dust resuspension significantly influenced particle measurements in the field.

Article Tier 2

Tire and road wear particles contamination in infiltration ponds sediments: occurrence, spatial variability, size distribution and correlation with metals

Researchers examined tire and road wear particle (TRWP) contamination in infiltration pond sediments, characterizing their occurrence, spatial variability, size distribution, and correlation with heavy metals to assess the pollution dynamics of these road-derived particles in urban drainage systems.

Article Tier 2

Characteristics of Vehicle Tire and Road Wear Particles’ Size Distribution and Influencing Factors Examined via Laboratory Test

Researchers conducted laboratory tests to characterize the size distribution of tire and road wear particles under various conditions. The study found that factors such as driving speed, tire composition, and road surface characteristics significantly influence the size and quantity of wear particles released, which are a growing source of microplastic pollution.

Share this paper