0
Article Tier 2 Sign in to save

Can groundwater geochemistry and contaminants of emerging concern help elucidating microplastic  sources and possible transport pathways?

2026

AI summary Read the abstract

Scientists found tiny plastic particles (microplastics) in underground water sources in Italy by studying how water moves through different soil layers. The research shows that these plastic particles mostly come from nearby local sources rather than traveling long distances underground, and they get trapped when they hit clay or other dense soil layers. This matters because understanding how microplastics move through groundwater helps us better protect drinking water sources and figure out where plastic pollution is coming from.

The evidence of microplastics (MPs) in groundwater is still restricted to a few sites worldwide, mostly concentrated in China, South Korea, India, a few European countries, and the USA. Even when field data are presented, they are rarely combined with auxiliary data such as hydrogeological characterisation of the area, description of the well profiles and construction materials, screen location, water geochemistry, isotopic data, and other contaminants of emerging concern. Because MP pollution is virtually ubiquitous, analysing MPs data by itself can reveal scant information on its possible sources and pathways in the subsurface. This study focuses on the Massaciuccoli Lake Basin (Central Italy), a Ramsar-designated marshy coastal wetland characterised by long-term anthropogenic influence. Over the past century, extensive land reclamation, agricultural intensification, and canalization have altered the natural hydrological regime. Documented land subsidence of approximately 2–3 m over the last 70 years has further modified groundwater gradients and surface–subsurface interactions. The initial step includes building a robust hydrogeological conceptual model of the area, combining landuse, geological background information, stratigraphic profiles, groundwater analysis of major ions and trace elements, water stable isotopes, and contaminants of emerging concern. Secondly, we combine the conceptual model with MP data from five sampling points over two sampling campaigns to help identify MPs sources and pathways in the subsurface environment. Geologically, the area is characterised as a heterogeneous sequence of marine, transitional, and continental sediments. Stratigraphic logs available for four of the five piezometers indicate an alternation of sand, silt, clay, and peat layers. This stratification promotes both vertical segregation, where low-permeability clay and peat layers restrict downward transport, and lateral compartmentalization, where permeable sandy units act as preferential flow paths. Hydrogeologically, the system is characterized as a shallow unconfined alluvial aquifer with a strong meteoric contribution and direct hydraulic connection to surface waters. Electrical conductivity, major ion chemistry, and the contaminants of emerging concern occurrence patterns indicate that groundwater composition is distinct for each piezometer, suggesting limited lateral mixing and emphasizing localized flow systems. Despite this spatial variability, hydrochemical parameters show only minor temporal variation between sampling campaigns, indicating hydrological stability at the seasonal scale. The combination of stratigraphic heterogeneity and stable flow conditions suggests that MPs detected at individual piezometers are more likely to reflect local sources and short-range transport, rather than basin-scale homogenization. Consequently, MPs are expected to exhibit site-specific distributions, with transport dominated by near-surface flow paths and attenuation occurring through physical retention at lithological boundaries.

More Papers Like This

Article Tier 2

How soil moisture and flow regime drive microplastic transport in the vadose zone: insight from modelling and column experiments

AI summary Read the abstract

Scientists studied how tiny plastic particles move through soil toward underground water sources that we use for drinking water. They found that plastic particles travel very differently depending on how wet or dry the soil is - sometimes getting trapped, other times moving quickly through the ground. This research helps us better understand how microplastics might contaminate our groundwater supplies, which is important for protecting drinking water quality.

Article Tier 2

Effects of co-present mineral colloids on the transport of microplastics in porous media: The key role of hydrochemical and hydrodynamic conditions

AI summary Read the abstract

Scientists studied how tiny plastic particles (microplastics) move through soil and sand when mixed with natural clay particles. They found that the combination of different clay types and water conditions can either help microplastics travel further underground or trap them in place. This research helps us better understand how microplastics might contaminate groundwater sources that provide our drinking water.

Article Tier 2

Baseline Assessment of Microplastic Occurrence in Groundwater from Alluvial and Karst Aquifers

AI summary Read the abstract

Scientists tested groundwater from underground aquifers in Slovenia, the same types of water sources many communities rely on for drinking water, and found tiny plastic particles (microplastics) in nearly every sample tested. This matters because it shows that microplastics aren't just in oceans and rivers; they're making their way into the water beneath our feet, which could eventually end up in our taps, though more research is needed to understand what levels of exposure mean for our health.

Article Tier 2

Mechanistic insights into the pore-scale transport and retention of microplastics: bridging physical and geochemical controls

AI summary Read the abstract

Scientists modeled how tiny plastic particles move through underground soil and rock to figure out what makes them get trapped versus flow into groundwater supplies. They found that warmer water and certain narrow, twisty underground pathways cause more microplastics to get stuck—sometimes more than doubling how much sticks around—while faster-flowing water lets more particles slip through toward drinking water sources. This matters because it helps predict when and where groundwater (a major source of drinking water) is more vulnerable to microplastic contamination, especially as climate change warms groundwater temperatures.

Article Tier 2

The Effect of Polymer Type and Particle Concentration on Microplastic Transport Mechanisms in Saturated Porous Media

AI summary Read the abstract

Scientists studied how tiny plastic particles move through soil and groundwater by testing different types of plastics at various concentrations. They found that the amount and type of plastic affects how far these particles travel underground, and that bacteria growing on the plastic surfaces can change how they move through soil. This research helps us better understand how microplastics might contaminate our drinking water sources and food supply.

Research digests by email

When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.

Email me about

Share this paper