We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Application of high-resolution site characterisation tools and sampling methods for assessing microplastic migration beneath MSW dumpsites
Summary
Researchers used advanced site characterization tools, including cone penetration testing and hydraulic profiling, to track how microplastics migrate from old waste dump sites into deeper soil layers and groundwater. They found microplastics at significant depths, with high-permeability zones serving as preferential pathways for particle migration. The study demonstrates that legacy waste sites may be ongoing sources of subsurface microplastic contamination.
The study addresses a significant environmental issue: the accumulation of microplastics (MPs) in municipal solid waste (MSW) dumpsites and their migration into deeper soil and groundwater (GW). Given the global increase in plastic production and limited waste management, this topic is highly relevant. Furthermore, many studies lack robust methodologies for tracking MP movement through complex soil strata. This study presents an innovative approach, employing advanced site characterisation and sampling techniques, including cone penetration test (CPT), hydraulic profiling tool (HPT), continuous soil sampling, and discrete GW sampling. This integrated method facilitates the identification of high-permeability zones, enabling large-depth sampling while reducing cross-contamination risk. Key findings reveal a substantial MSW layer containing plastics, textiles, and metals in specific zones, while natural soils dominate other areas. Unsaturated zones are mainly sandy, with occasional low-compressibility clay layers. MP concentrations are notably high at the MSW-soil interface 6600-8800 items/kg and decrease significantly with depth to 300-700 items/kg in saturated zones. Smaller MPs (<500 µm), mainly polyethylene, polypropylene, polyamide, and polyester, dominate soil samples. In GW, MP levels range from 26 to 171 items/L, with fibers (<250 µm) comprising about 80 % of MPs, highlighting subsurface soils as partial barriers to MP migration.
Sign in to start a discussion.
More Papers Like This
Exploring the vertical transport of microplastics in subsurface environments: Lab-scale experiments and field evidence
Researchers investigated how microplastics move downward through soil using laboratory column experiments and field sampling of groundwater. They found that heavier rainfall, smaller particle size, and fiber-shaped microplastics all increased vertical transport through unsaturated soil. Field samples confirmed the presence of microplastics in both soil layers and groundwater, suggesting that surface plastic pollution can migrate into underground water supplies.
Vertical distribution and post-depositional translocation of microplastics in a Rhine floodplain soil
Researchers analyzed a 110-centimeter-deep soil profile from a German river floodplain and found microplastics at every depth, including in layers deposited before the 1950s, suggesting earthworms and plant roots transported particles downward over time. This vertical movement means small microplastics travel deeper into soils than previously thought and complicates using them as markers for recent human impact.
Subsurface transport and environmental risks of microplastic pollution: influence of land use and seasonal variability
Researchers systematically investigated how microplastics move vertically through soil across five different land use types during pre-monsoon and post-monsoon seasons. Dumpsites had the highest microplastic concentrations at nearly 40,000 particles per kilogram, while woodlands had the lowest at around 500 particles per kilogram. The study found that smaller microplastics traveled deeper into soil, especially after monsoon rains, and that land use type significantly influenced both the amount and composition of microplastic contamination.
Overlooked yet critical pathways for microplastics input to soil and groundwater system: Transport mechanisms and simulation predictions in landfill environments
Researchers systematically investigated how microplastics travel through landfill soils into groundwater, examining the effects of particle density, size, polymer type, temperature, and salinity on transport. The study used column experiments and computational modeling to reveal that landfill conditions create overlooked but critical pathways for microplastic contamination of soil and groundwater systems.
Vertical migration of microplastics in porous media: Multiple controlling factors under wet-dry cycling
Researchers studied how microplastics move vertically through sandy soil during cycles of wetting and drying, testing four common plastic types at various particle sizes. They found that smaller, more hydrophobic particles migrated deeper, and that frequent wet-dry cycles and the presence of dissolved organic matter accelerated downward movement. The findings suggest that microplastics in agricultural soils could potentially reach groundwater, posing risks to underground water quality.